Scientific Conference on Understanding and Managing SweetnessScientific Conference on Understanding and Managing SweetnessOldways Scientific Program for New Delhi, India • 17 September 2009Oldways Scientific Program for New Delhi, India • 17 September 2009

The key role of sweetnessin health-promoting diets and lifestyles

Adam Drewnowski, PhDAdam Drewnowski, PhDDirector, Center for Public Health NutritionDirector, Center for Public Health NutritionDirector, UW Center for Obesity ResearchDirector, UW Center for Obesity Research

School of Public Health and Community MedicineSchool of Public Health and Community MedicineUniversity of WashingtonUniversity of Washington

Seattle, WASeattle, WA

• If the human body is healthy, then all the foods that taste the best are also the most nutritiousAldebrandin of Siena 1606

• Whatever is the most delicious is also the most nutritious

Magninus of Milan 17th C

Basic principles of gastronomy and science

Jean-Pierre Flandrin Histoire de l’Alimentation, Paris, 1996

• Sugar is the universal flavoring; its applications have an infinite variety…

• Mixed with water, sugar produces sugar water, a refreshing, healthy pleasant drink.

Jean Anthelme Brillat-Savarin 1825

What is more delicious than sugar? What is more delicious than sugar? France 1825France 1825

What is more nutritious than sugar? US 1948

The energy of sunshine is crystallized in Dextrose sugar

The sugar phobia: UK 1975The sugar phobia: UK 1975

An addictive destructive drug William Dufty 1975 Even fruit juices are

addictive Heller & Heller 1991

Sugar is the world’s most dangerous food additive. Sugar addiction is more common than alcoholism

Robert Atkins 1977

Consumer

Cost

Variety

FoodBehavior

How people choose foodsHow people choose foods

Pleasure Energy density

Health

Taste

Access/time

Taste

Physiology of sweet taste

• SaltySalty NaNa+ + ions enter via ions enter via ion ion channelschannels

• SourSour Acid HAcid H++ ions block K ions block K++ outflow via channels outflow via channels

• Sweet Sweet 3-4 types of sweet 3-4 types of sweet receptorsreceptors on cell on cell surface surface

• Bitter Bitter 40-60 types of bitter 40-60 types of bitter receptorsreceptors on cell on cell

surface linked to surface linked to many many transduction transduction systemssystems

Sweetness equals nutritionBitterness equals dietary danger

• A single taste cell has many receptors for bitter and sweet

• Humans have 3-4 different taste receptors for sweet

• Sugars and intense sweeteners are structurally related

• Humans have 40-80 different taste receptors for bitter

• Compounds that elicit bitter taste are completely unrelated

• Bitter compounds are often toxic Bitter compounds are often toxic

Density of papillae can vary

PROP nontaster

PROP supertaster

What do infants like?What do infants like?

Infants like sweetInfants like sweet

Sweetness preferences are innateSweetness preferences are innate

0

2

4

6

8

10

12

14

16

18

0.05 0.1 0.2 0.3

Sugar concentration (mol/L)M

ean

volu

me

cons

umed

(ml)

Sucrose

Water

Desor, Maller and Greene, 1978

Infants prefer sweet liquidsInfants prefer sweet liquidsto plain waterto plain water

Sweet Sour Bitter

Facial expressions of 3-day old infants Steiner, 1977

Facial expressions of 3-day-old infants: the reflex taste response

Mennella and Beauchamp, Nutr Rev 1998

Liking

for sweetRejectionof bitter

What do children like?What do children like?

Foods that are familiar and sweetFoods that are familiar and sweet

Dimensions of children’s food preferences - a classic study (Birch 1979)

• Children ages 3-4 y tasted open faced sandwiches on whole wheat bread– margarine, margarine and mint jelly, peanut

butter, peanut butter and grape jelly, cream cheese, cream cheese and honey, cream cheese and caviar, cheddar cheese spread

• “Point to the sandwich you would like to eat the very best”– Sandwiches removed one by one - to give a

metric scale

Children also liked high calorie foods (Birch, 1979)

Peanut butter

Cream cheese+caviarMargarine+mint jelly

Cream cheese

The most preferred foods contained sugar and fat

Child 2

Cream cheese+honey

Cheddar cheese

Peanut butter+jelly

Margarine

Consumer

Cost

Variety

FoodBehavior

How people choose foodsHow people choose foods

Health

Taste

Access/time

Taste Pleasure Energy

density

0

10

20

30

40

0 10 20 30 40 50 60 70 80 90 100

water content (g/100g)

En

erg

y d

en

sit

y (

MJ

/kg

)

Fats Sweets

Energy density (MJ/kg) and water content

oil

butter

sugar

Soft drinks

candy

0

10

20

30

40

0 10 20 30 40 50 60 70 80 90 100

water content (g/100g)

En

erg

y d

en

sit

y (

MJ

/kg

)

Fats Sweets Dairy

oil

butter

sugar

candy

cheese

yogurtmilk

ice cream

Soft drinks

Energy density (MJ/kg) and water content

0

10

20

30

40

0 10 20 30 40 50 60 70 80 90 100

water content (g/100g)

En

erg

y d

en

sit

y (

MJ

/kg

)

Fats Sweets Meat Dairy

oil

ice cream

milk

meat

cheese

butter

sugar

Soft drinks

Energy density (MJ/kg) and water content

0

10

20

30

40

0 10 20 30 40 50 60 70 80 90 100

water content (g/100g)

En

erg

y d

en

sit

y (

MJ

/kg

)

Fats Sweets Grains Meat Dairy

oil

grains

milk

meat

cheese

butter

sugar

Soft drinks

Energy density (MJ/kg) and water content

0

10

20

30

40

0 10 20 30 40 50 60 70 80 90 100

water content (g/100g)

En

erg

y d

en

sit

y (

MJ

/kg

)

Fats Sweets Grains Vegetables Fruit Meat Dairy

milk

cheese

butter

sugar

meat

Soft drinks

Energy density (MJ/kg) and water content

What do children like?What do children like?

Foods that are energy-dense, Foods that are energy-dense, familiar, and sweetfamiliar, and sweet

Children like foods that are energy-dense and sweet!

(Wardle et al., Appetite 2001;37:217-223)

Best liked (-2 to +2) Least liked (-2 to +2)

1.91 Chocolate

1.88 Chocolate biscuits

1.88 Crisps (=chips)

1.88 Yogurt

1.84 Ice cream

1.83 Ice lolly (popsicle)

1.83 Fruit squash

1.77 Bread

1.67 Chicken

1.63 Plain biscuits

-0.62 Avocado

-0.59 Leeks

-0.56 Zucchini squash

-0.49 Melon

-0.45 Cottage cheese

-0.44 Sweet peppers

-0.31 Onion

-0.29 Liver

-0.25 Cabbage

-0.05 Parsnips

Saturday Evening Post 1948Saturday Evening Post 1948

Children like the foods they knowChildren like the foods they knowI don’t like it; I never tried it!I don’t like it; I never tried it!

-1

-0.5

0

0.5

1

1.5

2

0 20 40 60 80 100 120Have tried the food before (%)

Pre

fere

nc

e

tofu

avocado cottagecheese leeks

melon

chocolate

R2=0.4

Data from Wardle et al., 2001Data from Wardle et al., 2001

crisps

Children like sweet energy-dense Children like sweet energy-dense foodsfoods

-1

-0.5

0

0.5

1

1.5

2

0 2 4 6 8 10Energy density (kcal/g)

Pre

fere

nce

buttermargarine

chocolate

crisps

ice lollyfruit squash

tomatoesgreen beanscabbage

R2=0.14

Data from Wardle et al., 2001Data from Wardle et al., 2001

Preference Score (range -2 to +2)

2.01.51.0.50.0-.5-1.0

Ene

rgy

Den

sity

(kJ

/g)

5.0

4.0

3.0

2.0

1.0

0.0

strawb/raspberries

peach/pear/plum

melon

grapes

banana

apricot

apple

leeks

lettuce/cuc/celery

tomatoes

pars/turnip/swede

brocc/spin/greens

peas

green/runner/broad

potatoes

citrus

carrot

cabbage

red peppercauliflower

marrow/courgette

beans

Banana

Potatoes

Grapes

Apple

Children like energy-dense fruit best Children like energy-dense fruit best

(Wardle al, Appetite 2003)(Wardle al, Appetite 2003)

Is sugar to blame?

Is there something about sugars and satiety?

What is satiety?

• Satiety is defined as a state of fullness following a meal. Measures include:– Ratings of fullness after the meal– Ratings of hunger or desire to eat again– Food consumption at the next meal– Timing (onset) of the next meal

• Satiation is the state of fullness before the meal even ends– Size of that meal is the main measure

Next meal

time

Solid

Appetitive ratingsHunger, fullness, desire to eat, thirst

Liquid

Satiation

This meal

Satiation

Food records

Expectation: Subjects ingesting a preload will eat less at this/next meal

Variable interval: 15 min – 6h

Satiety

The satiety sequence

Research on sweetness and satiety

• Are liquids less satiating than solids?– Soft drinks vs. cookies

• Are liquid sugars not satiating?– Soft drinks vs. juices or milk

• Do intense sweeteners promote hunger?– Aspartame vs. milk

Compare liquids and solids

Next Meal

time

Solid

desire to eat

Same calories – different volume

Liquid

hunger

fullness

thirst

Liquids, solids and satiety:A direct test

Composition Cola Raspberry cookie

Carbohydrate (g) 81.5 69.0

Sugar (g) 81.5 48.0

Protein (g) 0 3.0

Fat (g) 0 0

Fiber (g) 0 1.5

Serving size 710 ml

(24 oz)

87 g

(6 units)

Total kcal 300 300

Almiron-Roig, Flores, Drewnowski, Physiol & Behav 2004;82:671

Beverage vs. cookie

Keep energy constant (300 kcal)– vary texture and time lag

Lunch

Lunch

Lunch

Lunch

2h

2h

20 min

20 min

Study design: 2 time delays

Breakfast

Breakfast

Breakfast

Breakfast

1.5h

1.5h

3.5 h

3.5 h

Almiron-Roig, Flores, Drewnowski, Physiol&Behav 2004;82:671

1

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8

9

930 1000 1030 1100 1130 1200 1230 1300

Hu

ng

er

(9-p

oin

t s

ca

le)

Early cola Early cookie Late cola Late cookie

Time (h)

Breakfast Lunch

Temporal profile of hunger ratings

Almiron-Roig, Flores, Drewnowski, Physiol&Behav 2004;82:671

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9

930 1000 1030 1100 1130 1200 1230 1300

Hu

ng

er

(9-p

oin

t s

ca

le)

Early cola Early cookie Late cola Late cookie

Time (h)

Breakfast Lunch

Temporal profile of desire to eat

Almiron-Roig, Flores, Drewnowski, Physiol&Behav 2004;82:671

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9

930 1000 1030 1100 1130 1200 1230 1300

Hu

ng

er

(9-p

oin

t s

ca

le)

Early cola Early cookie Late cola Late cookie

Time (h)

Breakfast Lunch

Temporal profile of fulness

Almiron-Roig, Flores, Drewnowski, Physiol&Behav 2004;82:671

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930 1000 1030 1100 1130 1200 1230 1300

Hu

ng

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(9-p

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ca

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Early cola Early cookie Late cola Late cookie

Time (h)

Breakfast Lunch

Temporal profile of thirst

Almiron-Roig, Flores, Drewnowski, Physiol&Behav 2004;82:671

Will cola spoil appetite for lunch?

0

200

400

600

800

1000

Early cola Early cookies Late cola Late cookies

kcal

Lunch (kcal)

Yes – if consumed just before lunch*

* *

Compare cola, juice and milk

ED=0.42 kcal/g

ED=0.42kcal/g

ED=0.42kcal/g

ED=0.0kcal/g

Orange juice

1% milk

Regular cola

Sparkling water

248 kcal

248 kcal

248 kcal

0 kcal

Almiron-Roig, Drewnowski Physiol Behav 2003;79:767

Same calories and volume – different beverage

Orange juice 1% milk Cola Water

Energy (kcal) 248 248 248 0

Volume (ml) 591 591 591 591

Carbs (g) 62 29 67 0

Sugar (g) 55 28 67 0

Protein (g) 0 20 0 0

Fat (g) 0 6 0 0

E.D. (kcal/g) 0.42 0.42 0.42 0

Study design• Thirty-two volunteers (14 men; 18 women) • Breakfast preload: beverage (248 or 0 kcal) and slice of dry

toast (100 kcal) at 9:35 am• Hunger, thirst, fullness, nausea and desire to eat measured

every 20 min (9-point scale)• Tray lunch served at noon (1,734 kcal)• Foods pre-weighed and plate waste measured

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9

935 1000 1020 1040 1100 1120 1140 1200 1230

Hu

ng

er

(9-p

oin

t s

ca

le)

Orange juice 1% milk Cola Water

Time (h)

Breakfast Lunch

Temporal profile of hunger ratings

Almiron-Roig, Drewnowski. Physiol Behav 2003;79:767

Temporal profile of desire to eat

1

2

3

4

5

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7

8

9

935 1000 1020 1040 1100 1120 1140 1200 1230

De

sir

e t

o E

at

(9-p

oin

t s

ca

le)

Orange juice Milk (1%) Cola Water

Time (h)

Beverage LunchAlmiron-Roig, Drewnowski Physiol Behav 2003;79:767

Time (h)

Breakfast Lunch

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9

935 1000 1020 1040 1100 1120 1140 1200 1230

Fu

llne

ss

(9

-po

int

sc

ale

)Orange juice Milk (1%) Cola Water

Temporal profile of fullness ratings

Almiron-Roig, Drewnowski Physiol Behav 2003;79:767

Temporal profile of thirst ratings

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2

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5

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8

9

935 1000 1020 1040 1100 1120 1140 1200 1230

Th

irs

t (9

-po

int

sc

ale

)Orange juice 1% milk Cola Water

Time (h)

Beverage LunchAlmiron-Roig Drewnowski Physiol Behav 2003;79:767

Lunch meal: 1734 kcalAdditional servings of the same foods

available from a side buffet

0

1000

2000

3000

4000

5000

6000

7000

OJ Milk Cola Water

En

erg

y in

tak

e (

kJ

)

0

1000

2000

3000

4000

5000

6000

7000

OJ Milk Cola Water

En

erg

y in

take

(kJ

)

Preload Lunch

Men Women

aa a b

c cd

Energy intakes at lunch were all the same – no compensation

Almiron-Roig Drewnowski Physiol Behav 2003;79:767

Conclusions

• Orange juice, 1% milk, and cola behaved in exactly the same way

• Calories reduced hunger more than did water; all four beverages quenched thirst

• There was no downward adjustment for energy consumed at breakfast for any of the caloric beverages tested

Final question:Final question:

Do intense sweeteners Do intense sweeteners promote hunger?promote hunger?

Sugars Study: Methods• N = 37 volunteers (19 men; 18 women), age 23y• Body mass index: 23.4 (men), 21.9 (women)• Hunger, thirst, fullness, and desire to eat measured

every 30 min (9-point scale)• Lunch foods pre-weighed by experimenters. Plate and

water waste measured.

Beverage Volume Calories

Aspartame 475 4

1% milk 495 213

No beverage 0 0

0

10

20

30

40

50

60

70

80

90

100

Hu

ng

er

(9-p

oin

t s

ca

le)

Aspartame Milk no bev

Time (h)

Breakfast Lunch

Temporal profile of hunger ratings

Almiron-Roig, Flores, Drewnowski, Physiol&Behav 2004;82:671

0

10

20

30

40

50

60

70

80

90

100

Hu

ng

er

(9-p

oin

t s

ca

le)

Aspartame Milk no bev

Time (h)

Breakfast Lunch

Temporal profile of fulness ratings

Almiron-Roig, Flores, Drewnowski, Physiol&Behav 2004;82:671

Energy Intakes at lunch

700

750

800

850

900

950

1000

1050

1100

kc

al

1% milk Aspartame No Bev

Perrigue et al. Presentation at Experimental Biology 2006 in San Francisco April 2006

Final question:Final question:

So what causes obesity?So what causes obesity?

Dietary fat

Sucrose

Eating in restaurants

Large meals

Fast foods

Eating too much

High GI carbs

High fructose corn syrup

Eating at home

Between-meal snacks

Vending machines

Walking too little

Liquid beverages Energy dense (solid) foods

Simple sugars Non-caloric sweeteners

Gluttony Sloth

What causes of obesity?Science has many answers

From fat… to sugar… to….

““Obesity is caused by eating too much fat, sugar, Obesity is caused by eating too much fat, sugar, starch and protein, by caloric and non-caloric starch and protein, by caloric and non-caloric

sweeteners; by meals and by snacks; by beverages sweeteners; by meals and by snacks; by beverages and by solid foods; by eating at fast foods and by solid foods; by eating at fast foods

restaurants and by eating at home”restaurants and by eating at home”

Drewnowski & Darmon AJCN 2005Drewnowski & Darmon AJCN 2005

Some recent publicationsSome recent publications

• We need studies on the satiating power of novel beverages

• Look at beverages consumed before, with, or after meals

Conclusions