dreams of the rarebit fiend: food and diet as instigators of bizarre and disturbing dreams (2015)

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ORIGINAL RESEARCH ARTICLEpublished: xx February 2015

doi: 10.3389/fpsyg.2015.00047

Dreams of the Rarebit Fiend: food and diet as instigators ofbizarre and disturbing dreamsTore Nielsen1* and Russell A. Powell2

1 Dream and Nightmare Laboratory, Center for Advanced Research in Sleep Medicine, Hôpital du Sacré-Coeur de Montreal, Department of Psychiatry, Universitéde Montreal, Montreal, QC, Canada

2 Department of Psychology, Grant McEwan University, Edmonton, AB, Canada

Edited by:

Anil K. Seth, University of Sussex,UK

Reviewed by:

Valdas Noreika, Medical ResearchCouncil, UKTom Froese, Universidad NacionalAutónoma de México, Mexico

*Correspondence:

Tore Nielsen, Dream and NightmareLaboratory, Center for AdvancedResearch in Sleep Medicine, Hôpitaldu Sacré-Coeur de Montreal, 5400Gouin Blvd West, Montreal, QC,H4J 1C5, Canadae-mail: [email protected]

In the early 1900s, the Dream of the Rarebit Fiend comic strip conveyed how thespicy cheese dish Welsh rarebit leads to bizarre and disturbing dreams. Today, theperception that foods disturb dreaming persists. But apart from case studies, someexploratory surveys, and a few lab studies on how hunger affects dreaming, there is littleempirical evidence addressing this topic. The present study examines three aspects of thefood/dreaming relationship; it attempts to: (1) assess the prevalence of the perception offood-dependent dreaming and the types of foods most commonly blamed; (2) determineif perceived food-dependent dreaming is associated with dietary, sleep or motivationalfactors; and (3) explore whether these factors, independent of food/dreaming perceptions,are associated with reports of vivid and disturbing dreams. Three hundred and ninetysix students completed questionnaires evaluating sleep, dreams, and dietary habitsand motivations. Items queried whether they had noticed if foods produced bizarre ordisturbing dreams and if eating late at night influenced their dreams. The perceptionof food-dependent dreaming had a prevalence of 17.8%; with dairy products being themost frequently blamed food category (39–44%). Those who perceived food-dependentdreaming differed from others by reporting more frequent and disturbing dreams, poorersleep, higher coffee intake, and lower Intuitive Eating Scale scores. Reports of disturbingdreams were associated with a pathological constellation of measures that includespoorer sleep, binge-eating, and eating for emotional reasons. Reports of vivid dreamswere associated with measures indicative of wellness: better sleep, a healthier diet, andlonger times between meals (fasting). Results clarify the relationship between food anddreaming and suggest four explanations for the perception of food-dependent dreaming:(1) food specific effects; (2) food-induced distress; (3) folklore influences, and (4) causalmisattributions. Research and clinical implications are discussed.

Keywords: nightmares, dreaming, sleep, food, diet, fasting, internal awareness

INTRODUCTIONFor millennia, people have believed that the foods they eat caninfluence their dreams. The Dream of the Rarebit Fiend comicstrip (see Figure 1), penned by Winsor McCay and published inthe New York Herald from 1904 to 1925, is a striking example ofhow such beliefs have been expressed repeatedly in popular cul-ture. Even today, anecdotes are common about how a recurrentdream, bizarre dream, or nightmare was triggered by eating a par-ticular food or by eating too much or too late at night. Yet thereis surprisingly little empirical research that directly addresses thequestion of food-dependent dreaming. Although evidence existsthat sleep may be facilitated or disrupted by different types offoods—for example, foods that are rich in tryptophan, caffeineor alcohol, or even specific foods such as milk, kiwis or tartcherry juice (see review in Peuhkuri et al., 2012)—the effectsof food on dreaming remain largely in the realm of specula-tion. Further, common beliefs and traditions about which foodsinfluence dreaming are not well-documented, even though such

subjective impressions might provide useful starting points formore objective research on the topic. The present study takes afirst step toward investigating this issue by exploring how peopleperceive food to influence their dreams and whether these percep-tions are associated with sleep characteristics and dietary habitsand motivations.

Evidence that food directly affects dreaming is scarce. Wefound, for example, a single correlational study of dietary pref-erences and dreaming (Kroth et al., 2007), conducted with 7 menand 42 women, which revealed that participants who expresseda preference for organic foods reported more frequent dreamrecall, recurring dreams and meaningful dreams, as well as moredreams containing particular themes such as flying, risk-taking,sex, and water. In contrast, participants who expressed a pref-erence for fast foods reported less frequent dream recall, as wellas fewer recurring dreams, nightmares, and sexual dreams. Whilethe authors of this study rightly consider the findings preliminary,the small sample size (especially for males), lack of correction

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Nielsen and Powell Food and dreams

FIGURE 1 | Sample Dream of the Rarebit Fiend comic strip by

Wilson McCay (aka Silas) that was popular in the early 1900’s

and influenced popular culture for many years. The cartoonsusually ended with the protagonist (who differed from cartoon to

cartoon) regretting having eaten Welsh rarebit, a dish of meltedspiced cheese on toast. In the present study, dairy products, includingcheese, and spicy foods were most often named by participants asfoods that induce disturbing dreams.

for multiple correlations, and other methodological weaknessessuggest caution in interpreting these findings.

We also found evidence of a single, industry-sponsored labo-ratory study on the effects of food on dreaming (British CheeseBoard, 2005). In 2005, the British Cheese Board conducted astudy with 200 volunteers on the effects of eating cheese ondreams. The study purportedly found no evidence for the notionthat eating cheese prior to sleep can induce nightmares, but didfind evidence that different types of cheese can induce different

types of dreams—for example, eating Stilton cheese often ledto crazy or vivid dreams while eating cheddar cheese often ledto dreams of celebrities. But although the results were widelyreported in the media [e.g., “Sweet dreams are made of cheese,”Anonymous (Daily Mail), 2005], they were never published in apeer-reviewed journal, and the available information about thestudy is extremely sparse.

If direct evidence about food-dependent dreaming is lacking,some indirect evidence can be gleaned from studies on the effects

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of hunger and thirst on dreaming, from how individuals dreamabout food, and from anecdotal information concerning people’sbeliefs about the effects of food on dreams. These three sources ofevidence are considered below.

HUNGER AND THIRST INFLUENCES ON DREAMINGHunger in the form of fasting was a known trigger of vivid dreamsand visions among indigenous peoples of North America (forreview and examples see Lincoln, 1970) and among some earlydream incubation cults such as the Oracles of Trophonius (Meier,1967, p. 109) and Amphiaros (MacCulloch, 1912) in Greece, andin even earlier Egyptian dream temples such as the Imuthes tem-ple in Memphis and the Thoth temple in Khimunu (Foucart,1912). In many of these contexts, fasting formed part of a questfor visionary contact with the spirit world that involved severalforms of privation and sacrifice, e.g., sleep deprivation, social iso-lation, exposure, or threats of animal attack. Causal relationshipsbetween fasting and dreams are not easy to discern from these his-torical and anthropological sources, but it was generally believedthat the absence of food, leading to acute or chronic hunger, cantrigger vivid, sometimes transformative dreams.

On a more prosaic level, hunger was apparently a trigger fora dream of Freud’s daughter, Anna, when she was 19 monthsold (Freud, 1900). Her celebrated “strawberry dream” took placefollowing a day in which she went without food after over-consuming strawberries and vomiting in the morning. In hersleep she called out “Anna F(r)eud, St’awbewy, wild st’awbewy,om’lette, pap!,” which Freud took to indicate that even this youngchild was capable of dreaming of the foods she hungered for.Freud considered the drives of hunger and thirst to constitute thesole somatic sources of very simple dreams of food and drink, thesimplest of wish-fulfillment dreams as it were.

Some support for these ancient beliefs and psychoanalyticimpressions was provided by O’Nell (1965), who examined rela-tionships between chronic food and thirst frustration and theappearance of food and liquids in the dreams of different cul-tural groups. Dream reports were contributed by young malesfrom four cultural groups that differed in “food frustration”scores. These scores were calculated on the basis of the pres-ence and severity of fasting, under-nutrition, and malnutritionin their respective cultures. Evaluation of food and drink themesin the dreams of these four groups revealed a clear correspon-dence between degree of food frustration and dreams of food, i.e.,higher food and thirst frustration was associated with more foodand thirst dreams, respectively.

Following discovery of REM sleep and its link with vividdreaming, further evidence was marshaled from laboratory set-tings that linked the motivational effects of hunger and thirst todreaming (Dement and Wolpert, 1958; Bokert, 1968). Dementand Wolpert (1958) collected a total of 15 REM sleep dreams fromthree subjects who were deprived of fluids for 24 h prior to sleep-ing in the laboratory on each of five nights. Five of the dreams(33%) contained thirst-related content, but these did not depictthe dreamer as thirsty or in the act of drinking. A more exten-sive study was conducted by Bokert (1968) involving 18 femalenurses who were deprived of food and drink for the 8 h prior tocoming to the sleep laboratory where they then ate a highly spiced

meal. Prior to awakenings from REM sleep for dream collection,a recording of the phrase “a cool delicious drink of water” wasplayed repeatedly. Using a detailed grid of drink-related words,dreams about liquids were seen to increase, with some sub-jects even dreaming about the stimulation phrase. Interestingly,those who had dreams of satisfying their thirst drank less uponawakening than did subjects who had dreams of simply beingthirsty.

Together, historical accounts and some systematic studies sup-port the notion that hunger and thirst may produce more vivid,bizarre, and personally significant dreams. The widespread beliefin the intentional use of fasting to stimulate dreaming likelyreflects this influence. Such studies are nonetheless limited inwhat they reveal about direct relationships between food anddreaming.

DREAMS ABOUT FOODClinicians have expressed an interest in dreams about food,frequently in relation to patient symptomatology. Hamburger(1958), for example, collected a large corpus of food and eat-ing dreams from four female analytic patients, two of whomwere normal weight with no eating problems, one of whom wasobese, and another of whom had bulimia. Of 1928 total dreamscollected by the patients, 229 (11.9%; range across patients: 10.6–18.1%) were judged to deal with themes of food, eating, andassociated settings, such as kitchens, dining rooms and restau-rants. In 3 of 4 patients, such dreams tended to diminish infrequency as psychotherapy progressed. In no cases did patientsnotice food dreams arising in response to feelings of hungerduring the preceding day nor did they report waking up fromthese dreams feeling hungry. Hamburger concluded that fooddreams constitute a typical theme that derives from latent “oralneeds,” essentially substituting one type of gratification (sexual,dependency) for another (alimentary).

Several content studies provide some indication of the preva-lence of food and drink themes in dreams. First, the prevalence oftaste and smell in dreams is moderately low; 36.6 and 39.0% ofparticipants retrospectively report having experienced any kindof gustatory or olfactory dream imagery, respectively, and preva-lence estimates from 2 to 3-week home logs are even lower: 13.4and 15.2%, respectively (Zadra et al., 1998). In the latter study,only 0.86 and 1.01%, respectively, of over 3300 dreams containedsuch imagery. Second, the Hall and van de Castle dream con-tent norms (Hall and van de Castle, 1966) indicate that foodas an object occurred in the dreams of only 1.4% of male and1.0% of female college students (1.2% overall), and the broadertheme of orality (including eating/drinking, being in a place of eat-ing/drinking, preparing or securing food/drink) was also relativelyinfrequent, occurring in the dreams of only 16.0% of males and17.0% of females. Third, the typical dream theme of “eating deli-cious foods” has a lifetime prevalence among University studentsof 30.7% (Nielsen et al., 2003). A similar value was found in alarger sample of internet respondents: 26.9% (4307 of 16,030)dreamed this theme at least once, including 23.0% (848 of 3681)of males and 28.0% (3459 of 12,349) of females (χ2

(1) = 35.69,p < 0.000001; unpublished). Among eating disordered patientswhose dreams were sampled in a single laboratory night, dreams




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of food were much more prevalent. One study found them in 58%of patients with bulimia, 26% of patients with anorexia, and 44%of patients with anorexia and bulimia combined (Dippel et al.,1987). Similarly, patients with a diagnosis of migraine headachewere retrospectively more likely to report taste (31%) and smell(36%) in their dreams than were control subjects (20 and 20%,respectively) (Lovati et al., 2014).

In sum, the few available studies of dreams about food reveala relatively low prevalence of dreams of eating per se, with thepossible exception of individuals with eating disorders and otherhealth conditions, but a higher prevalence of dreams about oralityand food associations. While limited, such findings nonethelessdemonstrate that dreaming about food and eating is not uncom-mon and also suggest that the effects of food on dreaming may beassociated with health and personality factors (see also review byStrickler, 2005).

BELIEFS ABOUT THE EFFECTS OF FOOD ON DREAMSBeliefs that dreams can be influenced by food are widespreadand often circulated—and recirculated—by the media. Dreamresearchers are frequently asked about food effects on dreams,often in advance of food-centric holidays such as Halloween(candy), Easter (chocolate), or Christmas (turkey, general glut-tony). An often-mentioned notion is the classic “Pickled Walnut”theory, of unknown origin, which stipulates that eating spicy orunusual foods before sleep will lead to bizarre dreams or night-mares. These beliefs have also had currency in common medicalopinion. For example, the famous psychoanalyst, Ernest Jones,in his influential treatise, On the Nightmare (1931), noted that“in the current medical view they [nightmares] are ascribed tophysical disturbances in the alimentary, respiratory or circula-tory system, disturbances of either an irritating nature, such asundigested food, or of a mechanical nature, such as a distendedstomach” (p. 344). He also named cucumbers as “the article offood that is most looked askance at in relation to Nightmare”(p. 38). Similar sentiments concerning the relationship of food tonightmares have been voiced by medical practitioners since antiq-uity; Hippocrates (1931), for example, stated that “monstrousbodies that are seen in sleep and frighten a man indicate [amongother possibilities] a surfeit of unaccustomed food....” (p. 443).

Perhaps not surprisingly then, beliefs about the effect of foodon dreams have remained current among the general public. Thiswas strikingly reflected in the recurring food themes of the previ-ously mentioned comic strip, Dream of the Rarebit Fiend, from theearly 1900s. Protagonists in these cartoons had bizarre or disturb-ing dreams that they blamed on their pre-sleep meals of Welshrarebit (a dish of melted spiced cheese on toast) or, less com-monly, mince pie. A similar literary reference is that of EbenezerScrooge attributing one of his ghostly visions to “an undigestedbit of beef, a blot of mustard, a crumb of cheese, a fragment of anunderdone potato” in Charles Dickens’ A Christmas Carol (1843).One journalist’s introduction to a piece about food and dreamsin New Scientist magazine (Jones, 2000) sums up this widespreadcultural belief as follows:

We’ve all heard the story a thousand times: eating too much foodjust before bed can give you bad dreams. Especially if it’s spicy, orfermented, and definitely if it’s cheese that smells like your sock

drawer. I’ve noticed it. My mom’s warned me about it. It’s establishedfact, isn’t it?

A prevailing belief in the power of cheese to induce bad dreamsappears to have also been the motivation behind the aforemen-tioned unpublished study sponsored by the British Cheese Board(2005): “‘Now that our Cheese and Dreams study has finallydebunked the myth that cheese gives you nightmares we hope thatpeople will think more positively about eating cheese before bed,’says Nigel White, British Cheese Board secretary.”

Although the belief that foods can affect one’s dreams appearsto be prevalent, little empirical evidence has been collected onthe issue. An early survey by Laird (1920) assessed 100 par-ticipants’ beliefs about dreaming, hypnosis, telepathy, and thesubconscious. Fifteen participants (15%) indicated that a causeof dreaming was the kind or amount of food eaten. This wasnonetheless a majority of the 28% of participants who gave apositive answer to this question (other causes mentioned were“worry,” “conscience,” and “disturbed sleep”).

In sum, a sampling of medical and popular culture refer-ences, along with an early survey study, indicates that belief inthe ability of food to affect dreams—especially in a negativefashion—has been and continues to be common. The presentstudy examines beliefs about food-dependent dreaming by ask-ing undergraduate students whether and how foods can affecttheir dreams and which foods are most influential. The study alsoassesses whether participants who did and did not report experi-encing food-dependent dreaming differed on measures of sleep,dreams, and diet-related habits and motivations, as well as therelationship of these same variables to reports of vivid and dis-turbing dreams independent of the perception of food-dependentdreaming.

MATERIALS AND METHODSPARTICIPANTSParticipants were 396 undergraduate students—130 males (Mage:21.6 ± 5.28 years), 264 females (Mage: 21.4 ± 5.10 years;t392 = 0.37, p = 0.715), and two for whom age and sex wereunspecified—enrolled in first-year psychology courses at aCanadian university. The study was approved by the university’sResearch Ethics Board. Each participant provided informed con-sent and received partial course credit for their participation.Responses from all 396 respondents were entered into correla-tional analyses. However, 14 participants failed to respond to oneof the food-related dreaming items, leaving a total of 382 par-ticipants for the group comparisons: 126 males (Mage: 21.6 ±5.33 years), 255 females (Mage: 21.4 ± 5.15 years; t379 = 0.39,p = 0.695), and one sex unspecified.

PROCEDURESThe questionnaires used in this study formed part of a largeron-line survey assessing food consumption patterns and variousaspects of behavioral and psychological functioning. Followingthe survey, participants read a thorough debriefing that explainedthe nature and importance of the study. The email address of theprimary researcher was also provided for students who wantedmore information. The survey measures used in the present studyare described below.





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Sleep Quality Scale (SQS)This 28-item questionnaire (Yi et al., 2006) assesses problems insleep quality over the past month, including daytime dysfunctiondue to sleepiness, restoration from sleep, difficulties in wakingor falling asleep, sleep satisfaction, and awakenings during sleep.Items are rated on a 4-point scale with endpoints labeled 1-neveror rarely (up to 1–3 times a month); 2-sometimes (1–2 timesa week); 3-often (3–5 times a week) and 4-almost always (6–7times a week). The SQS has been shown with college studentsto have strong internal consistency and test-retest reliability, aswell as strong concurrent and construct validity (Yi et al., 2006).In the present study, we used four of the SQS subscales: (1) day-time dysfunction due to sleepiness; (2) difficulty falling asleep; (3)sleep dissatisfaction; and (4) sleep maintenance problems. We alsoadded an in-house measure of sleep time, i.e., the average numberof hours slept per day. (All in-house scales and items used in thisstudy are presented in the Appendix).

Three Factor Eating Questionnaire (TFEQ; Stunkard and Messick,1985)The TFEQ is a 51-item self-report questionnaire that assesseseating-related thoughts and behaviors with three subscales (cogni-tive restraint, disinhibition, hunger). However, because the TFEQfactor structure has been questioned (Karlsson et al., 2000), wecalculated Karlsson et al.’s more psychometrically sound TFEQ18-item revised (TFEQ-18R) questionnaire from participants’raw scores. The three subscales of the TFEQ-18R include: cogni-tive restraint (CR; test-retest r = 0.81–0.93; Cronbach’s alpha =0.93), or the propensity to control eating to influence body weightand body shape; uncontrolled eating (UE; r = 0.80–0.86; CA =0.91), or the propensity to lose control over eating when feelinghungry or when exposed to external stimuli; and emotional eat-ing (EE; r = 0.75–0.83; CA = 0.85), or the tendency to overeatin response to dysphoric mood states, e.g., when feeling lonely,anxious, or depressed.

Intuitive Eating Scale (IES)This 21-item instrument (Tylka, 2006) measures an individual’spropensity to utilize physical hunger/satiety cues, rather than sit-uational and emotional cues, when deciding what, when andhow much to eat. It consists of three subscales: unconditionalpermission to eat (CA = 0.89), eating for physical reasons (CA= 0.86), and reliance on hunger/satiety cues (CA = 0.72). Onlythe latter subscale was used in the present study. IES scores,including reliance on hunger/satiety cues, are associated positivelywith psychological well-being and negatively with eating disor-der symptoms, body dissatisfaction, poor interoceptive aware-ness, pressure for thinness, and internalization of the thin-idealstereotype (Tylka, 2006).

Diet quality questionnaireThis in-house questionnaire was designed to estimate the qualityof participants’ diets by having them retrospectively report theextent to which they ate foods that are prototypically consideredto be “healthy” or “unhealthy,” as well as the amount of coffee theydrank. The questionnaire items were modified versions of scaleitems used by Thompson et al. (2000). Four items (green salads,vegetables, fruit, whole grains) were averaged to form a healthy

foods variable, and two items (non-diet soft drinks, low-nutrientsnacks) were averaged to form an unhealthy foods variable.

Eating Behavior QuestionnaireThis in-house questionnaire assessed select attributes of eatingbehavior that could potentially influence sleep and dreams. Oneitem asked if the participant was currently following a calorie-reducing diet; another assessed the longest time that elapsedbetween eating or drinking during a typical day—which weviewed as a proxy measure of short-term fasting. A third item,drawn from the Eating Disorders Diagnostic Scale (Stice et al.,2000), assessed the tendency to engage in binge-eating behavior.

Perceived Food-Dependent Dreaming (FDD) QuestionnaireThis in-house questionnaire assessed the perceived effects of foodon dreaming with three binary (yes/no) and three open-endedquestions. Two binary questions asked whether participants hadever noticed foods that led to disturbing dreams or bizarre dreamswhile a third asked whether they had ever noticed if eating lateat night had affected their sleep or dreams. [Dreams that areeither disturbing or bizarre may overlap to the extent that bothcan involve negative emotion. But the two are distinct in thatbizarre dreams, which contain impossible (e.g., flying) or improb-able (e.g., winning a lottery) events, are not necessarily negative].For participants who answered “yes” to each of the three binaryquestions, the following open-ended question asked participantsto give specific examples. From the eating late at night items, wecalculated a new variable specific to dreaming that was scored1 if participants mentioned an effect on dreams (rather thansleep) in response to the open-ended question and was scored 0otherwise. We then created a perceived food-dependent dream-ing (FDD) variable in which participants who reported eitherthat eating a particular food led to disturbing or bizarre dreamsor that eating late at night affected their dreams were given ascore of 1 (FDD+) and those who did not were given a score of0 (FDD−).

Dream Characteristics QuestionnaireDisturbing and normal dreams over the past 2 weeks wereassessed with a 7-item in-house questionnaire that assessed threeaspects of disturbing dreams (recall frequency, distress, #wake-ups) and four aspects of non-disturbing dreams (recall frequency,clarity, realism, color). To reduce the number of variables for sub-sequent correlational analyses, responses to the seven questionswere first subjected to a principal components factor analysiswith varimax rotation (Kaiser normalization). A clear two-factorsolution accounting for 58.2% of the variance emerged whichconsisted of a disturbing dreams factor (%variance = 34.7) thatcontained all three disturbing dreams items (component load-ings: DD-distress = 0.865; DD-wakeUp = 0.852; DD-freq =0.752), and a vivid dreams factor (%variance = 23.5) that con-tained the remaining four items (DR-realism = 0.777; DR-clarity= 0.732; DR-freq = 0.677; DR-color = 0.613). Disturbing dreamsand vivid dreams factor scores were used as primary endpoints forsubsequent analyses.

STATISTICAL ANALYSESDistributions of participants as a function of sex and responsesto the three FDD items were evaluated with χ2 analyses. FDD




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group differences on sleep, dreaming, and other variables werecompared using a series of MANCOVAs with FDD group (FDD+,FDD−) as between groups factors and the multivariable group-ings of dependent measures shown in Table 3. Effects were sub-sequently assessed with univariate statistics and post-hoc t-tests.Significance threshold was set at p < 0.05. To assess whetherdreams and food/diet measures were associated independent ofFDD status, partial correlations were conducted while covary-ing FDD status. Because of strong correlations observed betweendisturbed sleep and other measures, partial correlations thatcovaried relevant sleep disturbance scores were also conducted.

RESULTSDESCRIPTIVEAs shown in Table 1, 68 of 382 (17.8%) participants indi-cated that their dreams were affected either by eating particularfoods (11.5%) or eating late at night (9.5%). Food-dependencieswere observed in approximately equal proportions for disturbingdreams (8.9%) and bizarre dreams (7.6%). Distributions of food-dependencies for males and females did not differ for disturbingdreams (χ2 = 0.735, p = 0.391), bizarre dreams (χ2 = 0.414,p = 0.520), disturbing and bizarre dreams combined (χ2 =0.436, p = 0.606), or dreams affected by either foods or eating late(χ2 = 0.165, p = 0.684). The two sexes were therefore combinedfor all subsequent analyses.

Table 2 lists the categories and frequencies of foods that weregiven in response to the open-ended questions asking for detailsabout foods that influenced disturbing and bizarre dreams. Themost frequent category mentioned (see Figure 2) was dairy, andincluded cheese, milk, hot milk, ice cream, yogurt, pizza, and pou-tine. Other foods typically containing cheese (e.g., pasta) wereexcluded from this category only because they also contained apredominance of other ingredients. It was also unclear from par-ticipants’ mentions of “greasy” foods whether dairy was intended.Sweets and chocolate were the second most frequently mentioned

category of dream-influencing foods, although these were men-tioned more than twice as often for bizarre dreams (30.8%) thanfor disturbing dreams (12.5%; χ2 = 2.92, p = 0.088). The samewas true for vegetables, although these were only infrequentlymentioned. Conversely, spicy and starchy foods and meat wereall mentioned more than twice as often for leading to disturbingdreams as they were for leading to bizarre dreams.

The probability of observing this proportion of dairy-relatedfoods being named as responsible for either disturbing or bizarredreams was calculated with binomial tests using the expected pro-portion of a food type calculated as the likelihood of observingany of the 7 food types being named equally often, or 1/7 =14.28%. Thus, for disturbing dreams, the probability of observ-ing 14 out of 32 (43.8%) instances of dairy-related foods wasZ = 4.762, p < 0.0001. No other food type was statistically sig-nificant. For bizarre dreams, the probability of observing 10 outof 26 (38.5%) instances of dairy-related foods was Z = 3.527,p = 0.0004 while the probability of observing 8 out of 26 (30.8%)instances of sugar-related foods was Z = 2.245, p = 0.025. Noother food types were significant.

The open-ended question about whether eating late influencedsleep and dreams produced a total of 89 responses; of these, 36(40.4%) specifically mentioned changes in dreaming. A majorityof these respondents, 47.2%, indicated that eating late brought onnightmares or disturbing dreams; 22.2% indicated that eating latemade their dreams more bizarre, odd, strange, or crazy; 19.4%that they became more vivid, realistic or creative; 13.9% that theybecame more nonsensical or meaningless; 8.3% that they becamemore abundant; and 8.3% that they related more closely to theprevious day’s experiences.

QUESTIONNAIRE CORRELATIONSPearson correlations between all dependent measures of the studyare shown in Table 3. Measures are grouped by the multivariablescontrasted in the group comparisons in the following section.

Table 1 | Participants perceiving their bizarre or disturbing dreams to be influenced by food or by eating late at night.

Item† Males Females All Total

(N = 126) (N = 255) (N = 382)

Yes No Yes No Yes No

N (%) N (%) N (%) N (%) N (%) N (%)

1. Food causes disturbing dreamsa 9 (7.1) 117 (92.9) 25 (9.8) 230 (90.2) 34 (8.9) 347 (91.1) 381

2. Food causes bizarre dreamsb 8 (6.3) 118 (93.7) 21 (8.2) 235 (91.8) 29 (7.6) 353 (92.4) 382

3. Eating late affects sleep or dreamsc 29 (23.2) 96 (76.8) 71 (28.0) 183 (72.0) 100 (26.4) 279 (73.6) 379

4. Eating late affects dreamsd 12 (9.6) 113 (90.4) 24 (9.4) 230 (90.6) 36 (9.5) 343 (90.5) 379

5. 1 or 2 (Food causes bizarre ordisturbing dreams)

13 (10.3) 113 (89.7) 31 (12.1) 225 (87.9) 44 (11.5) 338 (88.5) 382

6. 1 or 2 or 4 (FDD+: above item pluseating late affects dreams)

21 (16.7) 105 (83.3) 47 (18.4) 209 (81.6) 68 (17.8) 314 (82.2) 382

† One participant failed to complete item 1; three participants failed to complete items 3 and 4.aHave you ever noticed certain foods that seemed to lead you to have a disturbing dream? (no/yes).bHave you ever noticed certain foods that seemed to lead you to have a bizarre dream? (no/yes).cHave you ever noticed that eating late at night seems to affect your dreams or your sleep? (no/yes)d Dream-related comment given to “In what way does eating late at night affect your dreams or your sleep?” (no/yes).





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FOOD-DEPENDENT DREAMING GROUP COMPARISONSFDD status was used to compare participants who did and didnot perceive food to influence their dreams. FDD+ and FDD−groups differed significantly in age (t380 = 3.82, p = 0.004) with

Table 2 | Foods identified as influencing disturbing and bizarre

dreams.

Disturbing dreams Bizarre dreams

(N = 32) (N = 26)

N % N %

Dairy products 14 43.8 10 38.5

Cheese 4 12.5 2 7.7

Any dairy 4 12.5 4 15.4

Milk 2 6.3 1 3.8

Pizza 3 9.4 3 11.5

Poutine 1 3.1

Sugar 4 12.5 8 30.8

Sugar, sweets, candy 2 6.3 5 19.2

Chocolate 2 6.3 3 11.5

Spicy 6 18.8 2 7.7

Any spicy food 3 9.4 1 3.8

Pickles 3 9.4 1 3.8

Starch 5 15.6 1 3.8

Pasta 4 12.5

Noodles 1 3.1 1 3.8

Meat (inc. steak,hamburger, hot dog)

4 12.5 1 3.8

Vegetables (beans,peanut butter, carrots,mushrooms)

2 6.3 4 15.4

Generic 5 15.6 5 19.2

Junk, fast foods 2 6.3 3 11.5

Greasy or deep-fried 3 9.4 2 7.7

Because some participants identified more than one food type, the totals in each

column exceed 100%.

FDD+ participants being about 2.5 years older (M = 23.6 ± 7.0years) than FDD− participants (21.0 ± 4.6 years) on average.Due to this Age discrepancy, Age was examined as a covariate insubsequent comparisons.

Results for multivariate assessments with Age as a covari-ate are shown in Table 4. Three of the five multivariate effectswere significant (p < 0.05): Dreams/Nightmares (T = 0.020;F2,363 = 3.69, p = 0.026), Sleep Disturbance (Hotelling’s T =0.043; F5, 371 = 3.19, p = 0.008), and Eating Motivation (T =0.026; F4, 375 = 2.42, p = 0.048). The Dreams/Nightmares mul-tivariate main effect was due to the FDD+ group havinggreater scores on the disturbing dreams factor (F1, 364 = 5.35,p = 0.020). The Sleep Disturbance effect was due primar-ily to the FDD+ group having greater difficulty falling asleep(F1, 375 = 11.22, p = 0.001) and fewer hours of sleep per day(F1, 375 = 7.11, p = 0.008), but also to greater daytime dys-function (F1, 375 = 4.41, p = 0.036) and greater sleep dissatis-faction (F1, 375 = 4.42, p = 0.036). A single univariate differ-ence from the Diet Quality multivariable was that FDD+ par-ticipants reported drinking more coffee than did FDD− par-ticipants (F1, 373 = 5.73, p = 0.017). Finally, the multivariateEating Motivation effect was due primarily to FDD+ partic-ipants scoring lower than FDD− participants on IES relianceon hunger/satiety cues (F1, 378 = 8.16, p = 0.005), but theyalso scored marginally higher on TFEQ-18R emotional eating(F1, 378 = 3.10, p = 0.079).

To assess the extent to which late eating accounted for a por-tion of these main effects, we examined whether the distributionsof participants who reported late eating effects on dreams differedas a function of whether they thought that eating certain foodsinfluenced their dreams. This analysis revealed that 26.5% (9/34)of participants who claimed that eating certain foods affectedtheir dreams (category 5 in Table 1) also claimed that eating lateaffected their dreams, whereas only 9% (32/347) of participantswho did not claim that eating specific types of foods affectedtheir dreams did so (χ2 = 9.59, p < 0.006, Fisher exact test, 2-tailed). Thus, several participants who described specific, dream-altering foods also attributed dream changes to eating late atnight.

Following this, we reproduced the previous MANCOVAcomparisons while treating the effect of eating late on dreamingas a covariate. This changed the pattern of results in several

FIGURE 2 | Proportions of participants who identified specific food types as influencing disturbing and bizarre dreams.




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Table 4 | Mean (±SD) scores, multivariate and univariate main effects for participants saying “yes” (FDD+) or “no” (FDD−) to items querying if

particular foods or eating late at night affected their dreams.

Item FDD+ FDD−a Groupb (FDD comparison Groupc (FDD comparison with

(SD) (SD) with age covaried) age and late eating covaried)

F d p F d p

Multi-variable 1. Dreams/nightmares 3.69 0.026* 1.00 0.369

Disturbing dreams 0.25 ± 1.00 −0.06 ± 0.99 5.35 0.020* 1.57 0.211Vivid dreams 0.09 ± 0.97 −0.02 ± 1.02 1.84 0.176 0.41 0.524

Multi-variable 2. Sleep Disturbance 3.19 0.008** 2.52 0.029 *

SQS: daytime dysfunction 1.89 ± 0.70 1.73 ± 0.55 4.41 0.036 * 4.13 0.043 *

SQS: difficulty falling asleep 2.06 ± 0.78 1.74 ± 0.69 11.22 0.001*** 8.55 0.004**

SQS: sleep dissatisfaction 2.85 ± 0.86 2.62 ± 0.79 4.42 0.036* 0.32 0.571SQS: sleep maintenance 2.13 ± 0.77 2.01 ± 0.84 0.61 0.437 0.02 0.898Hours of sleep 6.81 ± 1.26 7.36 ± 1.29 7.11 0.008 ** 1.24 0.267

Multi-variable 3. Diet Quality 1.93 0.124 0.78 0.507

Healthy foods 5.10 ± 1.20 5.10 ± 1.38 0.03 0.861 0.00 0.982Unhealthy foods 3.15 ± 1.50 3.20 ± 1.43 0.03 0.869 0.49 0.486Regular coffee 4.05 ± 2.56 3.12 ± 2.21 5.73 0.017 * 1.66 0.199

Multi-variable 4. Eating Behavior 0.28 0.843 1.03 0.380

Currently on diete 1.85 ± 0.36 1.82 ± 0.38 0.50 0.478 0.75 0.387Time between meals 3.63 ± 1.11 3.72 ± 1.04 0.27 0.607 1.66 0.198Binge-eating 2.87 ± 1.67 2.92 ± 1.78 0.12 0.732 0.21 0.646

Multi-variable 5. Eating motivation 2.42 0.048* 1.96 0.105

TFEQ-18R: Cognitive restraintf 1.89 ± 0.47 1.88 ± 0.44 0.45 0.504 0.44 0.509TFEQ-18R: Uncontrolled eatingf 1.64 ± 0.36 1.58 ± 0.33 1.86 0.174 1.21 0.272TFEQ-18R: Emotional eatingf 1.47 ± 0.42 1.35 ± 0.39 3.10 0.079 5.82 0.016*

IES:Hunger/satiety cuesg 3.47 ± 0.69 3.69 ± 0.56 8.16 0.005** 3.38 0.067

F and p scores are shown for age-covaried main effects for FDD comparisons as well as for FDD comparisons with late eating effect also covaried.aFDD+/FDD−, participants reported “yes” or “no”, respectively to food-dependent dreaming (dreams were influenced by particular foods or by eating late).bFDD+.cFDD+ cohort while covarying perception of dreams being affected by “eating late”.d Multivariate F- and p-values are shown for rows in bold font, univariate statistics for all other rows.e1, yes; 2, no.f TFEQ−18R, Three-factor Eating Questionnaire 18-item Revised version.g IES, Intuitive Eating Scale.

***p < 0.001; **p < 0.01; *p < 0.05.

respects. Most importantly, the Dreams/Nightmares multi-variate group difference was no longer significant (T = 0.006,F2, 327 = 1.00, p = 0.369) and the groups no longer differed onthe disturbing dreams univariable (F1, 328 = 1.57, p = 0.211).The Sleep Disturbance multivariate effect was also diminishedbut remained significant (T = 0.034, F5, 335= 2.52, p = 0.029),as did univariate effects for daytime dysfunction (F1, 339 = 4.13,p = 0.043) and difficulty falling asleep (F1, 339 = 8.55, p = 0.004),but not for hours of sleep (F1, 339 = 1.24, p = 0.267). For DietQuality, the univariate difference for drinking coffee was elim-inated (F1, 330 = 1.67, p = 0.199). For Eating Motivation, themultivariate effect was diminished (T = 0.021, F4, 339 = 1.96,p = 0.105), and the reliance on hunger/satiety cues difference wasreduced to a trend (F1, 342 = 3.38, p = 0.067); the emotionaleating difference, however, became significant (F1, 342 = 5.82,p = 0.016).

RELATIONSHIPS BETWEEN DREAMING AND OTHER FACTORSTo assess general relationships between the two dreaming factorscores and other variables, independent of whether participantsreported food-dependent dreaming, we re-examined the correla-tions between disturbing dreams and vivid dreams and the othervariables reported in Table 3 after covarying Age and FDD sta-tus. As shown in Table 5, disturbing dreams were associated with alargely pathological constellation of variables. There was a strongrelationship with sleep disturbance as indicated by highly signif-icant correlations with all four SQS subscales (all p < 0.00001)but not with hours of sleep. Disturbing dreams were also pos-itively associated with being currently on a diet (p < 0.0004)and engaging in binge-eating (p < 0.00003), as well as withgreater cognitive restraint (p < 0.004), more uncontrolled eating(p < 0.003), more emotional eating (p < 0.020), and less relianceon hunger/satiety cues (p < 0.005). Disturbing dreams were not,




NIELTORE

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sleep dissatisfaction (F1, 339 = 0.32, p=0.571) or

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Table 5 | Pearson correlations between Disturbing Dreams and Vivid Dreams factor scores and sleep, diet, and eating measures for sample

with Age and FDD status covaried (columns 2,3), and with sleep disturbance measures also covaried (columns 4,5).

Disturbing Dreams Vivid Dreams Disturbing Dreams Vivid Dreams

Partial ra Partial ra Partial rb Partial rc

Sleep disturbance

SQS: daytime dysfunction 0.340**** −0.133*SQS: difficulty falling asleep 0.308**** −0.064SQS: sleep dissatisfaction 0.241**** −0.127*SQS: poor sleep maintenance 0.291**** 0.055Hours of sleep −0.023 0.104*

Diet quality

Healthy foodsb 0.030 0.141** 0.056 0.137**Unhealthy foodsc 0.006 −0.158** −0.034 −0.147**Coffee 0.087† 0.067 0.015 0.093†

Eating behavior

Currently on diet (1 = yes; 2 = no) −0.185*** −0.043 −0.096† −0.079Longest time between meals −0.005 0.188*** 0.026 0.183***Binge eating 0.217*** −0.070 0.151** −0.041

Eating motivation

TFEQ-18R: CR 0.155** 0.074 0.133* 0.080TFEQ-18R: UE 0.156** −0.164** 0.089† −0.144**TFEQ-18R: EE 0.122* −0.080 0.058 −0.054IES: Hunger/satiety cues −0.147** 0.090† −0.084 0.057

****p < 0.00001; ***p < 0.001; **p < 0.01; *p < 0.05; †p < 0.10; Abbreviations as in Table 4.aCovariates: Age, FDD status.bCovariates: Age, FDD status, all SQS subscales.cCovariates: Age, FDD status, SQS daytime dysfunction, SQS sleep dissatisfaction, Hours of sleep.

however, significantly related to the quality of participants’ diets,having only a marginal positive correlation with drinking coffee(p = 0.097). To determine if these relationships with disturbingdreams might be due to a mediating effect of sleep disturbances,correlations were recalculated with the SQS subscale scores par-tialed out. The relationship of disturbing dreams to being cur-rently on a diet was reduced to marginal significance (p = 0.070),while the relationship with binge-eating remained significant (p <

0.005). Among the motivational factors, however, only cognitiverestraint remained significant (p < 0.012), while emotional eat-ing (p = 0.276) and reliance on hunger/satiety cues (p = 0.111)became nonsignificant and uncontrolled eating was reduced tomarginal significance (p = 0.090).

The vivid dreams factor showed a profile of correlations largelyopposite to that for disturbing dreams, being associated withbetter sleep and more adaptive diet-related behaviors and moti-vations. More specifically, vivid dreams correlated negatively withdaytime dysfunction (p < 0.012) and sleep dissatisfaction (p <

0.016) and positively with hours of sleep (p < 0.051). Vivid dreamswere also associated with eating more healthy foods (p < 0.007)and fewer unhealthy foods (p < 0.003), and with longer timesbetween meals (p < 0.0004). There was also a negative associa-tion with uncontrolled eating (p < 0.002) and a marginal posi-tive association with reliance on hunger/satiety cues (p < 0.086).Covarying the relevant sleep measures (SQS daytime dysfunc-tion, SQS sleep dissatisfaction, and hours of sleep) had little effect

on the results for the remaining variables. The positive corre-lation with healthy foods (p < 0.009) and negative correlationwith unhealthy foods (p < 0.006) remained, while a marginallypositive correlation with drinking coffee (p < 0.077) emerged.The positive correlation with longer times between meals (p <

0.0006) and negative correlation with uncontrolled eating (p <

0.006) also remained; however, the marginally positive corre-lation with reliance on hunger/satiety cues was eliminated (p =0.280).

DISCUSSIONAmong a large sample of university undergraduates, we foundevidence supporting two general ideas about how food influencesdreams. First, results show that a substantial proportion ofindividuals (17.8%) perceive that food can render their dreamsmore bizarre or disturbing. These individuals are able to provideexamples—some quite specific—of foods that they believe affecttheir dreams; as well, many of them perceive that eating late atnight can affect their dreams. Second, we found evidence thatdisturbing dreams and vivid dreams are, in general, associatedwith several factors related to food consumption, such as differentmotivations for eating, with the effects for disturbing dreamsbeing largely mediated by sleep quality. In both sets of results,we found evidence that degree of psychopathology vs. wellnessmight mediate the relationship between food and the types ofdreams one has.





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PERCEPTIONS OF FOOD-DEPENDENT DREAMINGOur finding that 16.7% of males reported food-dependentdreaming is surprisingly similar to the early estimate by Laird(Laird, 1920) that 15% of males believed dreaming can be affectedby the type or amount of food eaten. Females were not studied byLaird but our estimate of 18.4% for females suggests that they donot differ substantially from males. It is noteworthy that our esti-mates of perceived food-dependent dreaming among universityjuniors are very similar to previous estimates of the prevalenceof food and orality themes in the dreams of college students inboth the US (16% males; 17% females; Hall and van de Castle,1966) and Japan (22%; Yamanaka et al., 1982). These similaritiesraise the intriguing possibility that participants who report food-dependent dreaming are also those who dream most about foodthemes.

While we consider the present findings preliminary andin need of further replication and extension, there are sev-eral reasons to expect that our relatively modest prevalenceestimates of perceived food-dependent dreaming are, in fact,underestimations. We queried participants about food in relationto only two common types of dreams, disturbing and bizarre,but details about other dream types or dream attributes couldprove even more informative. Probes about sex dreams, flyingdreams, lucid dreams, dreams of falling, or especially dreamsabout eating, drinking, and procuring or preparing food mightwell trigger other memories or attributions about the influenceof foods. Further, the present sample was restricted to primarilyyoung undergraduates who may have had less experience observ-ing the influence of food on their dreams or have had feweropportunities to be exposed to commonly held beliefs aboutrelationships between food and dreaming. Consistent with thispossibility, we found that FDD+ participants were on average 2.5years older than FDD− participants. A more thorough evaluationof the many possible influences of food on dreams, especially witholder participants, may well produce higher estimates of perceivedfood-dependent dreaming.

Although our exploratory use of open-ended responses forclassifying foods led to varying levels of descriptive detail, andthus limited comparability among participants, some trends nev-ertheless emerged. Dairy products were the foods most frequentlyidentified as influencing both disturbing (44%) and bizarre(39%) dreams. These proportions might be even higher in thatsome of the foods referred to by participants as “greasy” or“starchy” (e.g., pasta) may well have included cheese as a majoringredient. Sweet foods were also frequently mentioned as influ-encing dreams, but primarily in relation to bizarre (31%) ratherthan disturbing (13%) dreams. In contrast, spicy foods werepredominantly mentioned as a precursor to disturbing dreams(19%) as were starchy foods (16%) and meat (13%). It is note-worthy that dairy and spicy foods were the two categories mostoften named as affecting disturbing dreams; together they con-stitute a striking parallel to the spiced cheese dish of Welshrarebit. Cucumbers, which Jones (1931) described as the foodmost commonly believed to be a precursor of nightmares, wasmentioned once within this category in the form of pickles. Eatinglate was also perceived to affect dreams—primarily disturbingdreams (47%) but also dreams that participants characterized as

“bizarre,” “vivid,” “odd,” “strange,” or “crazy” (22%). A quar-ter of participants who perceived that specific foods affectedtheir dreams also reported that eating later affected their dreams(which is likely an underestimation given that some of those whogave an example of late eating affecting a change in sleep mayalso have been able to give an example of a change in dreaming);this effect of late eating may reflect the possibility that specificfoods eaten just before bed are those to which dream changes aremost likely to be attributed. But it may also reflect the fact thateating late negatively impacts sleep (Crispim et al., 2011) whichmay, in turn, influence dreaming. Thus, whereas dairy productswere seen as the most common instigators of both disturbing andbizarre dreams, other types of foods were mentioned as affectingpredominantly either disturbing dreams (spicy, starchy, meat) orbizarre dreams (sweets), with late eating in many instances possi-bly mediating the perceived relationship between particular typesof food and dreaming.

Comparisons of FDD+ and FDD− groups produced a set ofdifferences consistent with the possibility that FDD+ is associatedwith higher levels of psychopathology which may in turn playa role in the tendency to perceive food-dependent dreaming.FDD+ participants reported having more disturbed sleep anddisturbing dreams and, in a possibly related vein, drank morecoffee. The FDD+ group was also somewhat more likely to eatfor emotional reasons and was less sensitive to internal hungerand satiety cues. Tendencies toward emotional eating and lowsensitivity to hunger/satiety cues are interrelated (van Strienet al., 2005)—as they were in the present study (r = −0.214,p < 0.0001)—and have been associated with other pathologicalsymptoms. For example, high emotional eaters are characterizedby eating more when distressed (van Strien et al., 2012) and havemore blunted cortisol stress response (van Strien et al., 2013),poorer coping skills (Spoor et al., 2007), poorer interoceptivesensitivity (Herbert et al., 2013), and higher alexithymia and dif-ficulty in identifying feelings (Larsen et al., 2006; van Strien andOuwens, 2007). Emotional eating is also associated with posttrau-matic stress disorder (PTSD), with degree of emotional eatingbeing predictive of symptom severity (Talbot et al., 2013). Lateeating may play a role in mediating some of these effects insofar ascovarying the perceived effect of late eating on dreams somewhatdiminished the differences in pathology between the two groups.

The observed relationship between FDD+ and higher psy-chopathology is not generally consistent with the findings ofthe British Cheese Board (2005), i.e., that eating cheese priorto sleep does not induce nightmares. While our findings donot demonstrate empirically that nightmares result from eatingdairy, the fact that subjects themselves reported observing thisphenomenon, as well as our finding that such observations arecorrelated with psychopathological measures, together tend tosupport the opposite conclusion: that eating cheese may, in someindividuals, adversely influence subsequent dreaming.

Although the present results for perceived food-dependentdreaming are clearly limited by their correlational nature andby our use of subjective and retrospective reports, and shouldtherefore be considered as exploratory in nature, we nonethe-less suggest that they provide sufficient grounds for consideringfour possible explanations for why changes in dreams are often




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attributed to foods. Because our results are preliminary, we framethese explanations in the form of hypotheses for future study.

Food specificity hypothesisAccording to this hypothesis, many participants who report food-dependent dreaming are accurately describing cause-and-effectrelationships between specific foods or food categories and thecontent or quality of their dreams. In this context, FDD+ par-ticipants may differ from FDD− participants simply in havinga greater “dream sensitivity” to certain foods or in being moreaccurate observers of food-dream relationships. The purportedresults of the aforementioned unpublished study sponsored bythe British Cheese Board (2005)—which claimed, for example,that eating cheddar cheese led to dreams about celebrities—would, if valid, constitute an extreme example of this type ofeffect. The British Cheese Board report noted that cheese con-tains high levels of tryptophan which has been shown to reducestress and promote sleep. But although this might account for atendency for cheese to induce more pleasant or relaxing dreams,which the present results would dispute, it seems insufficientto account for a certain type of cheese (e.g., cheddar) lead-ing to a specific change in dream content (e.g., celebrities).Nevertheless, as previously noted, several foods contain nutrientsthat have been shown to impact sleep, and it is possible that cer-tain foods could potentially also impact dreaming—though onesuspects such effects would be of a more general nature (e.g.,calm vs. exciting dreams) than of a specific change in dreamcontent.

Food distress hypothesisClosely related to the above, this hypothesis proposes that theperception of food-dependent dreaming may result from non-specific effects of food intolerances and other adverse reactionsto food, the symptoms of which result in bizarre and disturbingdreams. As noted earlier, this notion dates back to antiquity, withHippocrates himself believing it to be a significant cause of night-mares. It differs from the food specificity hypothesis in proposingthat the effect on dreams is not the result of a specific link betweena particular food or type of food (or food nutrient) and dream-ing; rather, the effect is the result of an adverse change in one’ssomatic condition, especially in the alimentary system, whichcould potentially also have been induced by a non-food eventsuch as illness or other stressor. The adverse change in conditioncould either directly impact dreaming or indirectly affect dream-ing through the disruption of sleep patterns (Bohn et al., 2013;Dominguez-Ortega et al., 2014). In fact, sleep disruption is cor-related with a number of food items commonly known to inducegastrointestinal symptoms (Bohn et al., 2013). Among the morecommon are dairy products (e.g., 49% of patients with irritablebowel syndrome), beans/lentils, chocolate, and wheat (Benton,2007; Bohn et al., 2013). The fact that dairy products were byfar the most frequently named instigator of both bizarre and dis-turbing dreams in the present study supports this hypothesis,especially in view of the relatively high prevalence of lactose intol-erance among Canadians (20% of females and 12.3% of males;Barr, 2013). Also consistent with this possibility, many of thephysical symptoms of lactose intolerance (gas, bloating, cramps,

diarrhea) were reported spontaneously in response to our open-ended question about how eating late at night influences sleep anddreams.

Spicy foods were also singled out in our study as influencingdreams, particularly disturbing dreams (18.8%). Some pungentspices are known to affect sleep and might thus also alter dream-ing. For example, a meal containing a combination of Tabascosauce and hot English mustard caused healthy male athletes tosleep fewer hours and less efficiently (e.g., more time awake)than did a meal without these spices (Edwards et al., 1992).Moreover, rectal temperature was significantly higher duringthe first REM period of the night following the spiced meal, achange that might directly alter dream formation processes sinceREM sleep is the stage most conducive to copious, vivid dreamcontent.

In sum, food sensitivities and intolerances, especially lac-tose intolerance, could play a significant role in food-dependentdreaming. Assessment of food allergies, sensitivities, and intoler-ances in future work should clarify this potential explanation.

Folklore hypothesisThis hypothesis stipulates that an individual’s tendency to per-ceive particular foods as affecting their dreams originates in theassimilation of beliefs about food that have been transmittedinter-generationally within families, groups, or the broader cul-ture. While not incompatible with the previous hypotheses—acultural belief that, e.g., spicy foods can lead to bad dreamsmay in fact be accurate—the folklore hypothesis does not dependupon an individual’s accurate assessment of a food-dream rela-tionship. That is, some members of a culture may falsely believethat a prevalent folktale about, say, pickles causing bizarredreams applies to them when it does not. Thus, our find-ing that dairy products are the most frequently mentionedtype of food deemed to be responsible for inducing disturb-ing (43.7%) and bizarre (38.5%) dreams, while plausible froma lactose intolerance perspective, may also be consistent withthe folklore hypothesis. As previously mentioned, there appearsto be a belief prevalent in certain populations that dairy prod-ucts can affect dreams; this belief dates back at least to theearly 1900s, as exemplified by McCay’s Dream of the RarebitFiend cartoon series. While it is doubtful that contemporaryuniversity students are familiar with the Rarebit Fiend series,its wide influence at the time (see review in Wikipedia, 2014,http://en.wikipedia.org/wiki/Dream_of_the_Rarebit_Fiend) mayhave ensured that its central message (“eating spicy cheese leads tobizarre dreams”) would continue in common folklore for gener-ations. As earlier noted, the persistent prevalence of this belief inBritain, whatever its source, appears to have been the motivationbehind the unpublished study on the effect of cheese on dreamsby the British Cheese Board (2005).

A related notion is that cultural beliefs about the effectsof particular foods may interact with the ingestion of thosefoods such that the interaction brings about the culturallysanctioned belief. Thus, eating a lot of cheese before goingto bed while being reminded that this will surely causebizarre dreams may enhance the likelihood that bizarre dreamswill occur.


http://en.wikipedia.org/wiki/Dream_of_the_Rarebit_Fiend




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Misattribution hypothesisThis hypothesis proposes that some perceived linkages betweenfood and dreams may be false, with the connection to food, or aparticular food, being a misattribution of the real cause. As shownin the preceding section, folklore may have a particularly stronginfluence on this type of misattribution. For example, studentswho are taught to believe that cheese can induce nightmares maybe highly prone to attributing bad dreams to a pizza they ate thenight before a stressful exam rather than to their worries about theexam. Interestingly, FDD+ participants may be especially proneto misattributing the cause of a dream in this way if their lowreliance on hunger/satiety cues is representative of a more gen-eral lack of internal awareness which then leads them to seek anexternal explanation for their dreams.

As should be clear from the above discussion, these four expla-nations for the perception of food-dependent dreaming are notmutually exclusive. Any particular instance of a perceived food-dream relationship may result from a combination of two or moreof these factors.

GENERAL RELATIONSHIPS BETWEEN FOOD AND DREAMINGIndependent of participants’ beliefs in food-dependent dreaming,the present study also found evidence of at least two relationshipsbetween food and dreaming. The first relationship, which was alsonoted for the perception of food-dependent dreaming, reflects apathological constellation of variables that are uniquely associ-ated with disturbing dreams. In addition to disordered sleep, thesevariables include being on a diet, binge-eating, cognitive restraint,uncontrolled eating, emotional eating, and reduced reliance onhunger/satiety cues. The association of these variables with dis-turbing dreams could not be attributed uniquely to disorderedsleep because correlations with the other measures persisted evenwhen disordered sleep was covaried.

In contrast to the above, the second type of relationshipbetween food and dreaming reflects a constellation of wellnessmeasures uniquely associated with vivid dreams. These measuresinclude better sleep, a healthier diet, longer daily intervals with-out eating, and less uncontrolled eating. Again, the relationshipsheld even when the sleep measures were covaried, thus excludingbetter sleep as a unique explanation for the relationship.

These two opposing patterns of correlations partially replicatethe preliminary findings of Kroth et al. (2007). Whereas the lat-ter authors reported that dream recall, recurrence, pleasantnessand incidence of several specific themes, such as sexuality, risk-taking and flying, were all positively correlated with the frequencyof eating organic foods, we found a positive correlation between amore general measure of dream vividness that overlaps conceptu-ally with their measures (dream recall especially) and a measureof eating healthy foods. Similarly, whereas Kroth et al. found anegative correlation between dream recall and a preference foreating junk foods, we too found a negative correlation betweenvivid dreams and eating unhealthy foods. One finding reportedby Kroth et al. that we failed to replicate was a negative correlationbetween nightmares and a preference for eating junk foods; thatis, they found that less frequent nightmares were associated with apreference for unhealthy foods, whereas we found no associationbetween disturbing dreams and diet quality.

The present findings further demonstrate relationshipsbetween dietary patterns and disturbing and vivid dreams. In par-ticular, cognitive restraint, emotional eating, and reduced relianceon hunger/satiety cues were associated with disturbing dreamswhereas uncontrolled eating was associated with both disturb-ing dreams (higher scores) and vivid dreams (lower scores). Atleast two of these measures, emotional eating and reliance onhunger/satiety cues, may reflect individual differences in visceralor affective awareness. If this is the case, these findings, in additionto the general findings about food-dependent dreaming, could berelevant to an understanding of how consciousness in the formof interoceptive awareness may contribute to dream formation.For example, alexithymia, and the alexithymia component fac-tor difficulty in identifying feelings, are both elevated in severaltypes of eating disorders (Troop et al., 1995), as well as in sub-jects who report more disturbing dreams (Nielsen et al., 2011).This, and the fact that individuals with eating disorders frequentlyreport disturbing dreams, e.g., increased ineffectuality, feelings ofimpending doom, hostility, anxiety, anger (Brink and Allan, 1992;for review see Lauer and Krieg, 2004), suggests that a chronicinability to access interoceptive sensations may be a factor com-mon to both eating disorders and disturbing dreams. This furthersuggests that therapeutic approaches that promote a general-ized awareness and identification of feelings—which may includefeelings within one’s dreams (e.g., Gendlin, 1986)—may be par-ticularly helpful in the treatment of both disturbed dreaming andeating disorders.

Particularly intriguing is our finding that participants whoreported experiencing longer daily intervals without eating alsoreported more vivid dreams. As noted earlier, fasting has beenutilized since ancient times as a means of inducing vivid dreams.The present results suggest that even brief periods of food depri-vation within a day may be sufficient to produce a similar effect.This possibility is interesting in view of growing research indicat-ing that intermittent fasting—consisting of periodic intervals of12–24 h with little or no food—can have beneficial effects on bothphysical health and cognitive abilities (e.g., Longo and Mattson,2014). These findings are especially relevant if the longer intervalswithout eating reported in the present study typically occurredeither following sleep (resulting in a skipped breakfast) and/orpreceding sleep (after an early supper), in which case these partic-ipants may have regularly experienced extended periods of fooddeprivation consistent with an intermittent fasting protocol. Ifso, then the relationship of food deprivation with vivid dreamsfound in the present study may be associated with, or the resultof, a general improvement in cognitive functioning resulting fromexposure to periods of intermittent fasting. (See also Zilberter andZilberter, 2013, for a discussion of empirical evidence concerningthe benefits vs. adverse effects of skipping breakfast). This pos-sibility is further supported by the fact that our scores on vividdreams and longest time between meals were both positively cor-related with scores on the Attentional Function Index (r = 0.181,p = 0.001; r = 0.157, p = 0.004, respectively), a standardizedself-report measure of cognitive functioning (Cimprich et al.,2011) that was included in the survey as part of a questionnaire setfor a different study. If replicated, this relationship between briefperiods of fasting and vivid dreams might be useful in helping




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individuals to procure vivid dreams for use in creative pursuits orpsychotherapy. It is noteworthy, however, that intervals of fastingmay be confounded by a tendency to sleep late in the morning;“sleeping-in” may facilitate more vivid dreams because it takesplace closer to the peak of the circadian REM sleep propensityrhythm (for review see Nielsen, 2011).

It is perhaps ironic that one of the earliest theories of disturb-ing dreams—that it is often the result of foods we have eaten—hasgenerated such little empirical research. Moreover, when the pos-sibility has been considered, it has often been in the form of whatJones (1931) aptly referred to as a “half-jocular remark concern-ing the assimilable capacity of the evening meal” (p. 13). Theimpact of food on dreams may, however, be deserving of moreserious consideration. For example, as previously noted, PTSDhas been found to be associated with emotional eating (Talbotet al., 2013); in view of the present results, this might mean thatthe disordered eating patterns associated with PTSD play a rolein exacerbating or maintaining the chronic nightmares that con-stitute a major symptom of PTSD. This in turn suggests thattargeting the development of healthier patterns of eating may bea useful adjunct in the treatment of PTSD. The present resultsalso suggest that dreams, and perceived food-dream relationships,may be useful indicators of food intolerances and maladaptivepatterns of eating.

Further research on the topic seems warranted. This shouldinclude additional survey research using a more refined set ofitems as informed by the present findings, as well as experimen-tal research which directly manipulates foods eaten and assessestheir effects on dreaming. Of interest would be assessments ofthe extent to which certain foods—especially those, like Welshrarebit, combine dairy and spiciness—and particular eating pat-terns play a role in the exacerbation of chronic nightmares, aswell as of the relationship of vivid dreams to intermittent periodsof food deprivation and improvements in cognitive functioning.Such studies may even cast light on how a seeming relic fromcartoon history, the Dream of the Rarebit Fiend, achieved suchpopularity and continues to portray a common belief about foodand dreams today.

ACKNOWLEDGMENTSNatural Sciences and Engineering Research Council of Canada(Grant #312277) and Canadian Institutes of Health Research(Grant #MOP-115125).

SUPPLEMENTARY MATERIALThe Supplementary Material for this article can be found onlineat: http://www.frontiersin.org/journal/10.3389/fpsyg.2015.

00047/abstract

REFERENCESAnonymous (Daily Mail). (2005). Sweet Dreams are Made of Cheese. Available

online at: http://www.dailymail.co.uk/health/article-362101/Sweet-dreams-cheese.html (Accessed Sep 12, 2005).

Barr, S. I. (2013). Perceived lactose intolerance in adult Canadians: a nationalsurvey. Appl. Physiol. Nutr. Metab. 38, 830–835. doi: 10.1139/apnm-2012-0368

Benton, D. (2007). The impact of diet on anti-social, violent andcriminal behaviour. Neurosci. Biobehav. Rev. 31, 752–774. doi:10.1016/j.neubiorev.2007.02.002

Bohn, L., Storsrud, S., Tornblom, H., Bengtsson, U., and Simren, M. (2013).Self-reported food-related gastrointestinal symptoms in IBS are common andassociated with more severe symptoms and reduced quality of life. Am. J.Gastroenterol., 108, 634–641. doi: 10.1038/ajg.2013.105

Bokert, E. (1968). The Effects of Thirst and a Related Verbal Stimulus on DreamReports. Doctoral dissertation, New York University.

Brink, S. G., and Allan, J. A. (1992). Dreams of anorexic and bulimicwomen. A research study. J. Anal. Psychol. 37, 275–297. doi: 10.1111/j.1465-5922.1992.00275.x

British Cheese Board. (2005). Sweet dreams are made of cheese. Unpublisheddocument.

Cimprich, B., Visovatti, M., and Ronis, D. L. (2011). The attentional func-tion index–a self-report cognitive measure. Psychooncology 20, 194–202. doi:10.1002/pon.1729

Crispim, C. A., Zimberg, I. Z., dos Reis, B. G., Diniz, R. M., Tufik, S., and de Mello,M. T. (2011). Relationship between food intake and sleep pattern in healthyindividuals. J. Clin. Sleep Med. 7, 659–664. doi: 10.5664/jcsm.1476

Dement, W., and Wolpert, E. (1958). The relationship of eye movements, bodymotility, and external stimuli to dream content. J. Exp. Psychol. 55, 543–553.doi: 10.1037/h0040031

Dickens, C. (1843). A Christmas Carol. London: Chapman & Hall.Dippel, B., Lauer, C., Riemann, D., Majer-Trendel, K., Krieg, J. C., and Berger,

M. (1987). Sleep and dreams in eating disorders. Psychother. Psychosom. 48,165–169. doi: 10.1159/000288048

Dominguez-Ortega, G., Borrelli, O., Meyer, R., Dziubak, R., De Koker, C.,Godwin, H., et al. (2014). Extraintestinal manifestations in children with gas-trointestinal food allergy. J. Pediatr. Gastroenterol. Nutr. 59, 210–214. doi:10.1097/MPG.0000000000000391

Edwards, S. J., Montgomery, I. M., Colquhoun, E. Q., Jordan, J. E., and Clark,M. G. (1992). Spicy meal disturbs sleep: an effect of thermoregulation? Int. J.Psychophysiol. 13, 97–100. doi: 10.1016/0167-8760(92)90048-G

Foucart, G. (1912). “Dreams and sleep: Egyptian,” in Encyclopedia of Religion andEthics, Vol 5, ed J. Hastings (New York: Charles Scribner’s Sons), 34–37.

Freud, S. (1900). The Interpretation of Dreams. New York, NY: Basic Books.Gendlin, E. T. (1986). Let Your Body Interpret Your Dreams. Wilmette, IL: Chiron

Publications.Hall, C., and van de Castle, R. I. (1966). The Content Analysis of Dreams. New York,

NY: Appleton-Century-Crofts.Hamburger, W. W. (1958). The occurrence and meaning of dreams of food and

eating: I. Typical food and eating dreams of four patients in analysis. Psychosom.Med. 20, 1–16. doi: 10.1097/00006842-195801000-00001

Herbert, B. M., Blechert, J., Hautzinger, M., Matthias, E., and Herbert, C. (2013).Intuitive eating is associated with interoceptive sensitivity. Effects on body massindex. Appetite 70, 22–30. doi: 10.1016/j.appet.2013.06.082

Hippocrates. (1931). “Dreams,” in Hippocrates, On the Universe, Vol. IV, edsHippocrates, W. H. S. Jones, and Heraclitus (Boston, MA: Harvard UniversityPress), 421–447.

Jones, E. (1931). On the Nightmare. New York, NY: Liveright.Jones, N. (2000). The nightmare before Christmas. New Sci. 44–45.Karlsson, J., Persson, L. O., Sjostrom, L., and Sullivan, M. (2000). Psychometric

properties and factor structure of the Three-Factor Eating Questionnaire(TFEQ) in obese men and women. Results from the Swedish ObeseSubjects (SOS) study. Int. J. Obes. Relat. Metab. Disord. 24, 1715–1725. doi:10.1038/sj.ijo.0801442

Kroth, J., Briggs, A., Cummings, M., Rodriguez, G., and Martin, E. (2007).Retrospective reports of dream characteristics and preferences for organic vs.junk foods. Psychol. Rep. 101, 335–338. doi: 10.2466/pr0.101.1.335-338

Laird, D. A. (1920). The duty of the psychopathologist to the man on the street.J. Abn. Psychol. 14, 406–410. doi: 10.1037/h0073678

Larsen, J. K., van Strien, T., Eisinga, R., and Engels, R. C. (2006). Gender differ-ences in the association between alexithymia and emotional eating in obeseindividuals. J. Psychosom. Res. 60, 237–243. doi: 10.1016/j.jpsychores.2005.07.006

Lauer, C. J., and Krieg, J. C. (2004). Sleep in eating disorders. Sleep Med. Rev. 8,109–118. doi: 10.1016/S1087-0792(02)00122-3

Lincoln, J. S. (1970). The Dream in Primitive Cultures. Baltimore, MD: The Williams& Wilkins Co.

Longo, V. D., and Mattson, M. P. (2014). Fasting: molecular mechanisms andclinical applications. Cell Metab. 19, 181–192. doi: 10.1016/j.cmet.2013.12.008




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Lovati, C., DeAngeli, F., D’Amico, D., Giani, L., D’Alessandro, C. M., Zardoni, M.,et al. (2014). Is the brain of migraineurs "different" even in dreams? Neurol. Sci.35(Suppl. 1), 167–169. doi: 10.1007/s10072-014-1762-0

MacCulloch, J. A. (1912). “Fasting (Introductory and non-Christian),” inEncyclopedia of Religion and Ethics, Vol 5, ed J. Hastings (New York, NY: CharlesScribner’s Sons), 759–765.

Meier, C. A. (1967). Ancient Incubation and Modern Psychotherapy. Evanston, IL:Northwestern University Press.

Nielsen, T. (2011). “Ultradian, circadian, and sleep-dependent features of dream-ing,” in Principles and Practice of Sleep Medicine, 5th Edn., eds M. Kryger, T.Roth, and W. C. Dement (New York, NY: Elsevier), 576–584.

Nielsen, T. A., Zadra, A. L., Simard, V., Saucier, S., Stenstrom, P., Smith, C., et al.(2003). The typical dreams of Canadian university students. Dreaming 13,211–235. doi: 10.1023/B:DREM.0000003144.40929.0b

Nielsen, T., Levrier, K., and Montplaisir, J. (2011). Dreaming correlates ofalexithymia among sleep-disordered patients. Dreaming 21, 16–31. doi:10.1037/a0022861

O’Nell, C. W. (1965). A cross-cultural study of hunger and thirst manifested indreams. Hum. Dev. 8, 181–193. doi: 10.1159/000270303

Peuhkuri, K., Sihvola, N., and Korpela, R. (2012). Diet promotes sleep duration andquality. Nutr. Res. 32, 309–319. doi: 10.1016/j.nutres.2012.03.009

Spoor, S. T., Bekker, M. H., van Strien, T., and van Heck, G. L. (2007). Relationsbetween negative affect, coping, and emotional eating. Appetite 48, 368–376.doi: 10.1016/j.appet.2006.10.005

Stice, E., Telch, C. F., and Rizvi, S. L. (2000). Development and validation of the eat-ing disorder diagnostic scale: a brief self-report measure of anorexia, bulimia,and binge-eating disorder. Psychol. Assess. 12, 123–131. doi: 10.1037/1040-3590.12.2.123

Strickler, R. D. (2005). Dreams about food and eating: a literature review. SleepHypn. 7, 1–21.

Stunkard, A. J., and Messick, S. (1985). The three-factor eating questionnaireto measure dietary restraint, disinhibition and hunger. J. Psychosom. Res. 29,71–83. doi: 10.1016/0022-3999(85)90010-8

Talbot, L. S., Maguen, S., Epel, E. S., Metzler, T. J., and Neylan, T. C. (2013).Posttraumatic stress disorder is associated with emotional eating. J. Trauma.Stress 26, 521–525. doi: 10.1002/jts.21824

Thompson, F. E., Kipnis, V., Subar, A. F., Krebs-Smith, S. M., Kahle, L. L.,Midthune, D., et al. (2000). Evaluation of 2 brief instruments and a food-frequency questionnaire to estimate daily number of servings of fruit andvegetables. Am. J. Clin. Nutr. 71, 1503–1510.

Troop, N. A., Schmidt, U. H., and Treasure, J. L. (1995). Feelings and fantasy ineating disorders: a factor analysis of the Toronto Alexithymia Scale. Int. J. Eat.Disord. 18, 151–157. doi: 10.1002/1098-108X(199509)18:2<151::AID-EAT2260180207>3.0.CO;2-E

Tylka, T. L. (2006). Development and psychometric evaluation of a measure ofintuitive eating. J. Couns. Psychol. 53, 226–240. doi: 10.1037/0022-0167.53.2.226

van Strien, T., Engels, R. C., Van Leeuwe, J., and Snoek, H. M. (2005). The Sticemodel of overeating: tests in clinical and non-clinical samples. Appetite 45,205–213. doi: 10.1016/j.appet.2005.08.004

van Strien, T., Herman, C. P., Anschutz, D. J., Engels, R. C., and deWeerth, C. (2012). Moderation of distress-induced eating by emo-tional eating scores. Appetite 58, 277–284. doi: 10.1016/j.appet.2011.10.005

van Strien, T., and Ouwens, M. A. (2007). Effects of distress, alexithymia andimpulsivity on eating. Eat. Behav. 8, 251–257. doi: 10.1016/j.eatbeh.2006.06.004

van Strien, T., Roelofs, K., and de Weerth, C. (2013). Cortisol reactivity anddistress-induced emotional eating. Psychoneuroendocrinology 38, 677–684. doi:10.1016/j.psyneuen.2012.08.008

Yamanaka, T., Morita, Y., and Matsumoto, J. (1982). Analysis of the dream contentsin Japanese college students by REMP-awakening technique. Folia Psychiatr.Neurol. Jpn. 36, 33–52.

Yi, H., Shin, K., and Shin, C. (2006). Development of the sleep quality scale. J. SleepRes. 15, 309–316. doi: 10.1111/j.1365-2869.2006.00544.x

Zadra, A. L., Nielsen, T. A., and Donderi, D. C. (1998). Prevalence of auditory,olfactory, and gustatory experiences in home dreams. Percept. Mot. Skills 87,819–826. doi: 10.2466/pms.1998.87.3.819

Zilberter, T., and Zilberter, E. Y. (2013). Breakfast and cognition: sixteen effectsin nine populations, no single recipe. Front. Hum. Neurosci. 7:631. doi:10.3389/fnhum.2013.00631

Conflict of Interest Statement: The authors declare that the research was con-ducted in the absence of any commercial or financial relationships that could beconstrued as a potential conflict of interest.

Received: 23 September 2014; accepted: 09 January 2015; published online: xxFebruary 2015.Citation: Nielsen T and Powell RA (2015) Dreams of the Rarebit Fiend: food anddiet as instigators of bizarre and disturbing dreams. Front. Psychol. 6:47. doi: 10.3389/fpsyg.2015.00047This article was submitted to Consciousness Research, a section of the journal Frontiersin Psychology.Copyright © 2015 Nielsen and Powell. This is an open-access article distributed underthe terms of the Creative Commons Attribution License (CC BY). The use, distributionor reproduction in other forums is permitted, provided the original author(s) or licen-sor are credited and that the original publication in this journal is cited, in accordancewith accepted academic practice. No use, distribution or reproduction is permittedwhich does not comply with these terms.


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Supplemental Material Appendix: In-house survey items

Item Response choices

Dream characteristics

1. A disturbing dream is any dream that contains very

negative or unpleasant emotions. How many

disturbing dreams did you recall during the past two

weeks?

a. None

b. 1-2

c. 3-4

d. 5-6

e. 7-8

f. 9-10

g. 11-12

h. 13-14

i. 15 or more (that is, on average, more than one

per night)

2. How distressed were you by these disturbing

dreams?

Not at all Moderately Extremely

1 2 3 4 5 6 7

3. In general, what percentage of these disturbing

dreams were so bothersome that you were forced to

wake up (as opposed to just naturally waking up at

that time)?

a. 0%

b. 10%

c. 20%

d. 30%

e. 40%

f. 50%

g. 60%

h. 70%

1. 80%

J. 90%

k. 100%

4. How many dreams that were NOT disturbing did

you recall over the past two weeks?

a. None

b. 1-2

c. 3-4

d. 5-6

e. 7-8

f. 9-10

g. 11-12

h. 13-14

i. 15 or more (that is, on average, more than one

per night)

5. In general, how clearly were you able to recall your

non-disturbing dreams from the past two weeks?

Not at all Very

1 2 3 4 5 6 7

6. In general, how realistic were your non-disturbing

dreams from the past two weeks (that is, your dreams

made sense even if some of the elements were unusual

or impossible, such as having an ability to fly)?

Not at all Very

1 2 3 4 5 6 7

7. How often were these dreams in colour? Never Half the time Always

1 2 3 4 5 6 7

Perception of food-dependent dreaming

1. Have you ever noticed certain foods that seemed to

lead you to have a disturbing dream?

a. No b. Yes

2. What foods have you noticed that seemed to lead

you to have a disturbing dream (please be as specific

as possible)?

Open-ended

3. Have you ever noticed certain foods that seemed to

lead you to have a bizarre dream?

a. No b. Yes

4. What specific foods have you noticed that seemed

to lead to bizarre dreams?

Open-ended

5. Have you ever noticed that eating late at night

seems to affect your dreams or your sleep?

a. No b. Yes

6. In what way does eating late at night affect your

dreams or your sleep (please be as specific as

possible)?

Open-ended

Sleep length On average, how many hours do you sleep per day

(including sleeping that occurs both at night and during

the day)?

a) 3 hrs or less

b) 4 hrs

c) 5 hrs

d) 6 hrs

e) 7 hrs

f) 8 hrs

g) 9 hrs

h) 10 hrs

i) 11 hrs or more

Diet quality

1. How often do you eat green salad (with or without

other vegetables)?

1 = Never

2 = 1 to 3 times per month

3 = 1 to 2 times per week



6 = 1 time per day

7 = 2 times per day

8 = 3 times per day

9 = 4 times per day

10 = 5 or more times per day

2. How often do you eat vegetables (raw, cooked,

canned or frozen), NOT COUNTING potatoes and

salad?

same

3. How often do you eat fruit (raw, cooked, canned or

frozen), including berries?

same

4. How often do you eat whole grain foods, such as

whole grain bread or pasta, brown rice, oatmeal

porridge, or wheaties?

same

5. How often do you consume NON-diet soft drinks

(e.g., Coke, Pepsi, Dr. Pepper, etc.)?

same

6. How often do you eat low nutrient snacks like

cookies, potato chips, and candy bars?

same

7. How often do you drink regular coffee (coffee that

contains caffeine)?

same

Eating Behavior

1. Are you presently on a calorie restricting diet to

lose weight?

A = yes; B = no

2. During a typical day, from when you get up in the

morning to when you go to bed, what is the longest

amount of time that passes during which you do not

eat anything or have any calorie-containing drink

(such as a non-diet soft drink or coffee with cream

and/or sugar)?

a. less than 1 hour

b. 1 to 2 hours

c. 2 to 3 hours

d. 3 to 4 hours

e. 4 or more hours

3. How many DAYS per week on average over the

past 6 MONTHS have you eaten an unusually large

amount of food and experienced a loss of control

(you feel that you couldn’t stop eating or control

what or how much you were eating)?

# days/week:

0 1 2 3 4 5 6 7

dreams of the rarebit fiend: food and diet as instigators of bizarre and disturbing dreams (2015)

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