caffeine: a positive addition to a healthy lifestyle? ross grant phd australasian research institute

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Page 1: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute
Page 2: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Caffeine:A positive addition to a

healthy lifestyle?

Ross Grant PhD

Australasian Research Institute

Page 3: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

“ Coffee-drinking is used for social engagement, leisure, enhancement of work performance and well-being.”

“Unlike other [functional foods]….the wide use of coffee-drinking impacts a broad demographic (from children to elderly), with a wide spectrum of health benefits.

Dorea J.G. etal. Br J Nutr (2005), 93:773-782

Page 4: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

“Tea acts as a stimulant and, to a certain extent, produces intoxication. The action of coffee and many other popular drinks is similar. The first effect is exhilarating. The nerves of the stomach are excited; these convey irritation to the brain, and this in turn is aroused to impart increased action to the heart and short-lived energy to the entire system. Fatigue is forgotten; the strength seems to be increased. The intellect is aroused, the imagination becomes more vivid.

“Because of these results, many suppose that their tea or coffee is doing them great good. But this is a mistake. Tea and coffee do not nourish the system.

“The continued use of these nerve irritants is followed by headache, wakefulness, palpitation of the heart, indigestion, trembling, and many other evils; for they wear away the life forces. Tired nerves need rest and quiet instead of stimulation”. Ministry of Healing p326

Page 5: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Caffeine Useby Age and Sex

Australia & New Zealand SDA 2001

0%

10%

20%

30%

40%

50%

11-18 years 19-29 years 30+ years

Never Tried Past use Current use

Page 6: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

The issue:

In recent times the ingestion of tea and coffee has become a topic of debate within the Adventist community.

                                             

Page 7: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

The issue:

Is the introduction of caffeine into the SDA diet a beneficial adjunct to an already well-balanced lifestyle?

Page 8: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Background: origins and sources of caffeine

Molecular structure of caffeine identified by German chemist Runge in 1918

Page 9: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Background: origins and sources of caffeine

Coffee drinking in the middle east is traceable to the 15th centurySufi monks drank coffee to stay awake during prayers (Yemen, Arabia)By 1510 coffee was

widely used in all levels of Arab society from Cairo to Mecca

Page 11: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Common dietary sources of caffeine

Food/Beverage Caffeine content

Instant coffee (1 tsp) 60-80 mg/250 mL

Percolated coffee 60-120 mg/250 mL

Instant decaffeinated 2 mg/250 mL cup

Tea 10-50 mg/250 mL

Tea decaffeinated 1 mg/250 mL cup

Coca-Cola 36-50 mg/375 mL

Milk Chocolate 20 mg/100g* bar

Energy Drinks (R.Bull) 80 mg/250mL can

Table 1: Caffeine content of selected foods (source: ANZFA caffeine report, 2001 and Choice Magazine online (Sept, 2001)). *An average sized Mars bar weighs 80g

Page 12: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Common dietary sources of caffeineGuarana

• Guarana is a woody climbing plant that is native to the Amazon basin

• Guarana seeds contain more than 4% caffeine by weight, in comparison with coffee beans which may contain up to 2.2% by weight depending on the variety

Page 13: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Absorption of Caffeine into the body

Caffeine is metabolized in the liver by CYP1A2and is converted into the three products paraxanthine, theobromine and theophyllineeach of these have physiological effects on the body. Peak caffeine blood levels reached in 30-40 minutes typical half-life of between 4-6 hours Once caffeine is absorbed, it is able to enter all body tissues and easily crosses the blood-brain, placental and blood-testicular barriers

Page 14: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Action of Caffeine on the body

PHARMACOLOGICAL REVIEWS Vol. 51, No. 1. 1999

Page 15: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Action of Caffeine on the body

Principle action of caffeine is thought to be through blocking adenosine receptors on nerve tissue.

SerotoninCaffeine

Page 16: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Function of Adenosine receptors

Adenosine levels are raised whenever there is an increase in the amount of energy (ATP) consumption compared to energy (ATP) synthesis.

Activation of adenosine receptors in various tissues allow the body to modulate cellular activity in response to decreasing energy (ATP) levels.

Page 17: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Distribution of Adenosine receptors in the body

Brain

Fat tissue

Pancreas

Muscle Heart

Lung

StomachLiver

www.survivaltechnology.com/.../ human-body.jpg

Lymphocytes

Page 18: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Action of Caffeine on the body

Receptor subtype

HEART CNS KIDNEY OTHER

A1 Heart rhythm

Decrease heart rate

& force of atrial contraction

& responsiveness to adrenaline

Wakefulness-decrease in electrical

excitability and inhibition of

excitatory amino acid (EAA) release

Antidiuresis Anti-lipolytic insulin enhancer

Anti hypertensive

Wound healing

Hair growth

A2A Regulates blood vessel tone-

dilation of the coronary arteries

supplying blood to heart and muscle

Anti-inflammatory – increases

cerebral blood flow

Wound healing

Anti – aggregation of platelets

Increases gastric mucosal blood flow (ethanol)

Page 19: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

The widespread prevalence of caffeine-sensitive (adenosine) receptors in the body suggests the likelihood of multi-organ involvement following caffeine consumption.

Action of Caffeine on the body

Page 20: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Immediate effects of CaffeinePositive:

Caffeine can increase serotonin and dopamine release in the brain; somewhat mimicking the effect caused by antidepressants. (Casas, 2004)

Elevated Mood; including increased;Feeling of wellbeing

Alertness

Energy

Sociability

Page 21: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Immediate effects of CaffeinePositive:Studies indicate that:

Caffeine decreases reaction times and improves vigilance, sustained attention and selective attention (Smith, 2004). Tasks requiring speed are more sensitive to caffeine’s benefits than tasks involving intellectual power (Snel, 2004).

NOTE: Caffeine seems to have either no effect or a negative effect on memory (Smith, 2004).

Page 22: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Immediate effects of CaffeineNegative:

Studies indicate that:Higher doses of caffeine produce:

AnxietyJitterinessUpset stomach

(Juliano and Griffiths, 2004)

Page 23: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Immediate effects of CaffeineNegative:

Studies indicate that:caffeine can exaggerate the body’s response to stress by increasing heart rate and blood pressure (Lane et al., 2002) It is possible that caffeine alone may induce an adrenocortical stress response during rest and in the absence of explicit stressful challenge (al'Absi and Lovallo, 2004)

Page 24: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: cardiovascular

James (2004) suggests that population studies of BP indicate that caffeine use could account for:

14% of premature deaths due to coronary heart disease, and

20% due to stroke.

Page 25: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: cardiovascular

A prospective study of 1971 middle-aged men, showed that heavy coffee consumption (814 mL or more/day), increased the risk of acute myocardial infarction or coronary death by up to 75% compared to non- coffee drinkers (Happonen et al., 2004).Caffeine has been shown to, dose dependently, increase serum homocysteine levels (Verhof et al., 2002, Panagiotakos et al., 2004)Increased serum cholesterol and urinary excretion of 8-hydroxy-2-deoxguanosine in rats (Sakamoto et al., 2005)

Page 26: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: osteoporosis

Basic science experiments show that caffeine increases calcium excretion in the urine

In a prospective study of ~ 35 000 women followed for 6.5 years a weak association of highest caffeine intake (>6 cups daily) was observed with osteoporosis

(Hansen et al., 2000).

Page 27: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: Urinary

A high caffeine intake (>400 mg/d) was associated with urinary urge incontinence in a study of almost 260 women (overall risk, 2.4%; 95% CI, 1.1-6.5),

Note: This is similar to the likelihood of urinary stress incontinence of a vaginal delivery compared with caesarean delivery (2.4%; 95% CI, 1.7-3.2) (Arya et al., 2000; Rortveit et al., 2003; Holroyd-Leduc and Straus, 2004).

Page 28: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: Brain

HeadacheCaffeine is considered a modest risk factor in chronic daily headache, (Gadoth and Hering-Hanit, 2005). Caffeine withdrawal headache, (beginning 1 to 2 days following cessation of regular caffeine use), can last up to a week (van Dusseldorp and Katan, 1990). Caffeine may disrupt sleep or aggravate mood, both of which may exacerbate headache (van Dusseldorp and Katan, 1990).

Page 29: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: Behavioural

DependenceCaffeine exhibits physical dependence in up to 30% of consumers (Griffiths and Chausmer, 2000)Some caffeine users may also demonstrate clinical dependence (Strain et al., 1994).

Withdrawal symptoms (start 12-24hr–last 2-9 days)Headache, fatigue, depressed mood, irritability, nausea, vomiting muscle pain/stiffness

Page 30: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: Behavioural

SleepSleep is one of the physiological functions most sensitive to the effect of caffeine in humans200mg caffeine will:

Prolong sleep latencyIncrease initial light sleepDecrease later deep sleepIncrease shifts between sleep stagesDecrease in subjective sleep qualityIncreased time taken to reach REM sleep

Page 31: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: Brain

Can precipitate the onset and/or exacerbation symptoms of anxiety disorders, including panic disorder and obsessive-compulsive disorder, (Smith, 2004). Caffeine can interfere with the action of medication used to treat anxiety disorders and depression (Greden et al., 1981; Jefferson, 1988). Long term caffeine use affects serotonin metabolism in the brain of rats: implications for depression (Haider etal 1998, Haleem etal 1995)

Page 32: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: pregnancy/foetus

Caffeine is cleared at a slower rate from the pregnant woman and foetus (t1/2 18hrs)Caffeine readily crosses the placenta into the foetus Metabolising enzymes not present in foetus or placenta (Grosso and Bracken, 2005). Foetus therefore exposed to caffeine and its metabolites for a prolonged periods of intra-uterine life.

Page 33: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: pregnancy/foetus

Conflicting reports - foetal developmentIncreased caffeine use may cause spontaneous abortionA decrease in intervillous placental blood flow has been documented after maternal ingestion of just 200 mg of caffeine (Kirkinen et al., 1983). May effect foetal oxygenation and nutrition (Ghidini, 1996) After reviewing several animal studies, Nakamoto (2004) suggests that caffeine may affect neurodevelopment; further human studies required

Page 34: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: Child

Insufficient research precludes a definite conclusion as to whether caffeine consumption during pregnancy leads to mood disorders in children.

However, cortisol, which is increased by caffeine, may influence the foetal hypothalamic-pituitary-adrenal axis which controls the stress response Prenatal stress has been linked to interference in neuron development in the serotonergic system in late gestation (Linnet et al., 2003; Lovallo et al., 2005).

Page 35: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeineNegative: Adolescence

Significantly higher anxiety scores were observed in caffeine dependent 13-17 year-olds (13.7 ± 7.7) compared with the non-dependent group (7.5 ± 5.9) (Bernstein et al., 2002).

It would be useful to study more about how much caffeine children consume, and how this may affect them as adolescents are currently exposed to the opportunity to consume large amounts of caffeine due to the introduction of energy drinks, and frequenting of coffee lounges.

 

Page 36: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeinePositive:

DiabetesCoffee drinkers in the highest category

(≥6 or ≥7 cups/day) showed a relative risk of 0.65. (4-6 cups/day) had a relative risk of 0.72 compared with the lowest category (0 or ≥2 cups/day). Two reasons were suggested for the apparent protective effect of caffeine against diabetes: 1. Coffee contributes antioxidants to the diet (Pulido et al., 2003; Svilaas et al., 2004). 2. Caffeine ingestion can acutely reduce glucose storage (Greer et al., 2001). However, authors don’t recommend increasing coffee consumption as other health effects should first be considered (van Dam and Hu, 2005).

ed

Page 37: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeinePositive:

GallstonesLeitzmann et al., ( 1999) reported that 4 cups of coffee per day showed a relative risk of gallstone formation of 0.55,

This indicates a 45% reduction in the risk of forming gallstones in moderately heavy coffee drinkers.

Colon Cancer Case-control studies seem to indicate a lower risk of colon cancer associated with coffee drinking, but cohort study results are less clear (Tavani and La Vecchia, 2004).

Page 38: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

Longer-term effects of CaffeinePositive:

Parkinson’s diseaseA 5-fold lower risk of developing PD was observed in those who drank over 4 medium cups of coffee per day.

This protection was not seen in decaffeinated coffee (Xu et al., 2005). Animal experiments also show that caffeine directly protects against the death of neurons in Parkinson’s disease (Xu et al., 2005).

Page 39: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

CONCLUSIONS

Almost 2000 research papers have been published that included caffeine as a research variable in the title in the last 10 years

Almost universal use of caffeine throughout the world have made well controlled studies difficult

Page 40: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

CONCLUSIONS Caffeine is a drug that blocks activation of a specific nerve receptor system

Benefits observed include reduced risk of Parkinson’s disease, type 2 diabetes, colon cancer and gallstones

These are offset by negative biological effects;physical dependence, exacerbation of anxiety

increased blood pressure & cardiac fatality risk

osteoporosis, urge incontinence,

potential harm to the foetus.

The collection of negative effects impact on the quality of life in the community.

Page 41: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

CONCLUSIONS

A lifestyle with moderate energy intake, exercise and a diet high in fruit and vegetables would not appear to benefit from the inclusion of caffeine; but would rather result in the addition of unnecessary negative physiological stressors.

Page 42: Caffeine: A positive addition to a healthy lifestyle? Ross Grant PhD Australasian Research Institute

“Tea acts as a stimulant and, to a certain extent, produces intoxication. The action of coffee and many other popular drinks is similar. The first effect is exhilarating. The nerves of the stomach are excited; these convey irritation to the brain, and this in turn is aroused to impart increased action to the heart and short-lived energy to the entire system. Fatigue is forgotten; the strength seems to be increased. The intellect is aroused, the imagination becomes more vivid.

“Because of these results, many suppose that their tea or coffee is doing them great good. But this is a mistake. Tea and coffee do not nourish the system.

“The continued use of these nerve irritants is followed by headache, wakefulness, palpitation of the heart, indigestion, trembling, and many other evils; for they wear away the life forces. Tired nerves need rest and quiet instead of stimulation”. Ministry of Healing p326