How To Eat, Drink, and Be Healthy

Walter C. Willett, MD, DrPHDepartment of Nutrition

Harvard School of Public Health

April 26, 2007

10-Year Coronary Incidence Per 10,000 Men

Keys, 1980

Incidence

0

1000

2000

3000

0 5 10 15 20 25% Diet Calories from Saturated Fat

Velika KrsnaZrenjanin

BelgradeMontegiorgio

Crevalcore

Corfu

Crete

Slavonia

Zutphen

west Finland

east Finland

Ushibuka

Tanushimaru

y=77+78xr=0.73

9.006

(Keys 1980)

0

10

20

30

40

50

0 40 80 120 160 200 240 280 320Per Capita Daily Meat Consumption (grams)

Col

on C

ance

r Inc

iden

ce /

100,

000

Wom

en

(Armstrong and Doll, 1975)

ROMCHI

COL

YUG

JAM

JAP

NIG

ISRNOR

PRPOL

HUN

FIN

DEN

SWENET FDR

ICEDDR

NZ

USA

CAN

UK

2.003

Carroll, 1975

TaiwanJapan

Ceylon

El SalvadorThailand

Panama

PhilippinesMexico

ColumbiaSpain

Greece

Poland

Puerto Rico

ChileVenezuela

Hong Kong

RomaniaYugoslavia

CzechoslovakiaItaly

Portugal

Bulgaria

Australia

NorwayFrance

FinlandHungary

BelgiumSwitzerland

SwedenGermanyAustria

CanadaUKNetherlands

USA Ireland

New ZealandDenmark

0.001

0

5

10

15

20

25

0 20 40 60 80 100 120 140 160Animal Fat Intake (g/day)

Age

Adj

uste

d D

eath

Rat

e / 1

00,0

00 p

op

0.001

21.004

To reduce your fat intake:

Eat more fruits, vegetables, and their juices. Most are naturally low in fat…and high in vitamins and minerals.

Here are some other ways to reduce fat in your food.

TRY INSTEAD OF

Butter-flavored granules Butter or margarine Nonfat yogurt Regular yogurt Nonfat salad dressings Regular salad dressings Angel food cake Devil’s food cake Fat-free cookies and crackers High-fat cookies and crackers

1: Use Nonfat Products

9.071

21.031

21.038

9.010

8.063

Effect of Trans and Saturated Fat (10% E) on Blood Lipids (vs Monounsaturated fat)

(Mensink & Katan, 1990)

Trans fat Saturated fat

Total cholesterol +6% +12%

LDL cholesterol +14% +18%

HDL cholesterol -12% 0%

LDL/HDL ratio +29% +18%

9.110

Blood lipids

Blood pressure

Thrombotic tendency

Insulin resistance

Oxidation

Homocysteine

Inflammation/endothelial dysfunction

Ventricular irritability & arrhythmia

Diet CHD

9.105R

Age-Adjusted Plasma CRP by Quintiles of Trans Fatty Acid Intake in the Nurses’ Health Study

0

0.5

1

1.5

2

Q1 Q2 Q3 Q4 Q5

CR

P (m

g/L)

Trans Fat Intake (Quintiles)

(Lopez-Garcia 2005)

(P, trend = <0.001)

8.097

Nurses’ Health Study (n=121,700)

Health Professionals Follow-up Study (n=52,000)

Nurses’ Health Study II (n=116,000)

Investigators: Frank Speizer, Bernie Rosner, Meir Stampfer, Graham Colditz, David Hunter, JoAnn Manson, Sue Hankinson, Eric Rimm, Edward Giovannucci, Alberto Ascherio, Gary Curhan, Charlie Fuchs, Fran Grodstein, Michelle Holmes, Frank Hu

1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000

DietOcsSmokingWeight/HtMed. Hist.

Diet Diet DietBlood

Diet Diet

1986 1988 1990 1992 1994 1996 1998 2000

Diet Diet DietBlood

Diet

1989 1991 1993 1995 1997 1999

Diet Diet Diet

0.198R

Nails

Nails

Blood

100

80

60

40

20

0

-20

-40

1%E 2%E 3%E 4%E 5%E

Trans

Sat

Mono

Poly

% C

hang

e in

CH

D

(Hu et al. 1997)9.131

Quintiles of poly

Quintiles of trans fat

Mul

tivar

iate

RR

of C

HD

Hu et al, 1997

(lowest)

9.049

1

0.7

0.880.8

0.710.92 0.91

0.63 0.73 0.71

1.05

0.870.71

0.360.320.81

0.66 0.55 0.630.31

0

1.2

Q5

(hig

hest

)

Q4

Q3

Q2

Q1

(low

est)

Q5 (highest)

Q4

Q3

Q1&Q2(lowest)

0

0.5

1

3.6 4.8 5.6 6.9

Multivariate Relative Risk of Sudden Death(Albert et al., 2002)

P = 0.007

Quartile of blood N-3 fatty acid (Mean, % of fatty acids)

9.129

Oil and Vinegar Salad Dressing and Risk of Coronary Heart Disease

(NHS, 1980-1994) (Hu et al. 1992)

0

0.2

0.4

0.6

0.8

1

1.2

1/month 1-4/month 2-4/week 5+/week

Multivariate Relative

Risk

Frequency of Salad Dressing Consumption

••

•

•

9.126

Conclusions1. CHD rates can be dramatically reduced by

nutritional means, but this will not be achieved by replacing saturated fat with carbohydrate.

2. We should abandon recommendations regarding % of energy from fat and avoid pejorative references to fat or “fatty foods”.

3. Advice about dietary fat should focus on replacement of saturated and trans fat with vegetable oil, including sources of N-3 fatty acids.

9.062

(Howard et al. 2006)

9.152

0.6

0.8

1

1.2

1.4

Q1 Q2 Q3 Q4 Q5

Saturated FatMonoPolyTrans

Multivariate RR’s of type 2 diabetes according to quintiles of specific types of dietary fat (mutually adjusted)

(Salmeron et al, 1999)

Quintiles of Fat Intake

Mul

tivar

iate

RR

25.004

Trans Fat and Weight Gain

A recent 5-year study of monkeys provides evidence that on an isocaloric diet with 35% of calories coming from fat, monkeys on the diet with 8% E trans fat gained more weight (7.2% vs 1.8%) than monkeys on the diet with an equivalent amount of fat, but as monounsaturated cis fat.

(Kavanagh K, et al. Presented June 2006)

29.187

Change in Waist Circumference over 9 Years in 16,587 Men (Koh-Banerjee, 2003)

Variable Waist Change (cm)

P

Trans fat vs poly (2% E) +2.7* <0.001

Total fiber (12 gm) -2.21* <0.001

Television watching (20 hr/wk)

+0.59 <0.001

Vigorous activity (25 MET/wk)

-0.38 <0.001

Weight training (>0.5 hr/wk) -0.91 <0.001

*Adjusted for measurement error26.092

Fatty Acids Intake

-7

-13

-25

14

64

68

119

-100 0 100 200 300 400

All fats for carbs, 5% ofenergy

Saturated fat for carbs, 5%of energy

Mono unsaturated fat forcarbs, 5% of energy

Poly unsaturated fat forcarbs, 5% of energy

trans fat for carbs, 2% ofenergy

trans fat for n-6 poly fat, 2%of energy

trans fat for mono fat, 2% ofenergy

Percent Change in Risk of Ovulatory infertility

36.005

“So scientists from Harvard Medical School just found that eating trans fat can cause women to become infertile . . . . [pause] . . . . . So, guys out there: If your condom breaks, just buy your girlfriend a bucket of KFC!”

--Jay Leno, Tonight Show (1/23/07)

8.102

0

0.5

1

1.5

Women ( 591cases )Wolk et al., 1999

Men ( 734 cases )Rimm et al., 1996

RRof

CHD

Cereal Fiber, Energy- Adjusted, g/day

0

0.5

1

1.5

2.2 3.1 4.93.8 7.7 2.2 3.7 5.0 6.8 9.7

8.064

Blood Glucose

Insulin

Easily Digested Carbohydrate

-

Blood Glucose

Insulin

Slowly Digested Carbohydrate

0

0 1 2 3 4 5 0 1 2 3 4 5 Time (hr) Time (hr)

25.027

Relative Risk of Type 2 Diabetes by Different Levels of Cereal Fiber and Glycemic Load

2.5 2.32.05

2.171.8 1.62

1.511.28 1

0

1

2

3

High Medium Low

High

Medium

LowRelativeRisk

>165 165-143 <143Glycemic Load

>5.8 g/day

2.5 -5.8 g/day

<2.5 g/day

(Salmeron et al,1997)

(ref)

WOMEN

9.038

Liu et al., 2000Body Mass Index (kg/M2)

Rel

ativ

e R

isk

9.072

1.16

2 2

0.94 1.19

1.81

1 1.1 1.42

0

0.5

1

1.5

2

2.5

<23 23-29 >29

Tertile 1 (lowest)Tertile 2

Tertile 3 (highest)

Relative Risk of Coronary Heart Disease

Attributable Risk of Coronary Heart DiseaseDue to Modifiable Diet and Lifestyle Risk

Factors in the NHS (1980 to 1994)Low Risk:

1. Non smoker2. BMI < 25 kg/m2

3. Exercise > ½ hr of brisk walking/day4. Good diet (upper 2 quartiles of score based on

low trans fat, high p/s ratio, low glycemic load,high cereal fiber, high fish, high total folate)

5. Alcohol 5+g/day

• Proportion at low risk = 3.1%• Population Attributable Risk = 82% (95% CI = 58-93%)

Stampfer et al, 20009.092

Percentage of Type 2 Diabetes Potentially Preventable by Simultaneous Reduction of Five

Modifiable Risk Factors (NHS) (Hu et al.)

Low Risk1. Nonsmoking2. BMI < 253. Moderate to vigorous exercise4. Diet score in upper 40% (low trans fat, high cereal

fiber, low glycemic load, high P:S ratio)5. Alcohol 5+ grams/day

Percent in low risk group: 4.1%Population attributable risk (PAR): 92% (82-96)

25.026R

Proportion of Colon Cancers that are Potentially Preventable by Simultaneous Reduction 6

Modifiable Risk Factors (HPFS)(Platz et al. 2000)

Low Risk1. BMI £25 kg/m2

2. Physical activity £30 min/day of vigorous –moderate activity

3. Alcohol <15 g/day or 15-30 g/day with supplemental folic acid

4. Folic acid supplement of ≥100 µg/day5. £3 pack – years of smoking6. Red meat £2 servings/week

Joint low risk group = 3.1% of populationPopulation attributable risk (PAR): 71% (33-92)

2.116R

Lowfat products whenever possible; calcium supplements are and effective substitute for preventing fractures

Importance is well-documented; greens and dark orange vegetables should be included. Even more frequent servings may be desirable

Whole-grain, minimally processed products should be emphasized

Ignores critical differences in types of fat. Monos appear desirable

Misleading as 2-3 servings of meat/day is probably unhealthy

Support for generous intake is well documented

21.002

21.090

Healthy Eating Pyramid

Healthy Eating Pyramid

21.092

21.094

21.058

21.054

21.055

21.056