10/22/2009

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DASH: an Eating Plan for

Lifelong Health

Lynn L. Moore, DSc, MPH

Preventive Medicine & Epidemiology

Boston University School of Medicine

2

DASH eating plan recommended by:

Primary Goals of Today’s Talk

� Re-assess the evidence for DASH

� Examine effects of DASH on health outcomes

in adults (in addition to BP)

� Look at new data on DASH and health

outcomes in children and adolescents

Secondary Goals

� Raise question of what constitutes a “DASH

eating plan”.

� Identify some unanswered questions

3

DASH Eating Plan (Adults)based on a 2,000 calorie diet

U.S. Department of Health and Human Services. Your Guide to Lowering Your Blood

Pressure with DASH. 2nd Edition, April 2006

Food Group Daily Servings

Vegetables 4-5

Fruits 4-5

Low-fat or fat-free dairy products 2-3

Grains (esp. whole grains) 6-8

Meats (lean), poultry, fish 6 or less

Nuts, seeds, dry beans, peas 4-5/week

Fats and oils 2-3

Sweets 5 or less/week

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Vegetables: broccoli (vit A), soy (Ca, potassium), beets, mushrooms, potatoes (B6), green leafy/spinach (vit A, Mg, Ca), tomatoes, (potassium, Mg) (fiber)

Fruit: melons, bananas, papaya, prunes, oranges (Mg, potassium, vit C, fiber), fortified juices (Ca)

Dairy: milk, yogurt, cheese(Ca, Potassium, Mg, vit D, phos, protein)

Major DASH Food Groups

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Original DASH Clinical TrialThree diets

� Control (typical American)

� Fruits and vegetables (K, mg, fiber)

� Combination: fruits, vegetables, low-fat dairy (K, mg, fiber, ca, pro)

� Isocaloric (no wt loss)

� 459 adults � 50% women

� 60% African-American

� Elevated BP: � SBP < 160 mm Hg

� DBP 80 – 95 mm Hg

� Intervention Period – 8 wks

6Appel LJ N Engl JMed 1997;336:1117-1124

120

122

124

126

128

130

132

134

0 1 2 3 4 5 6 7 8

Follow-up Time (wks)

SBP (mmHg)

Control

Fruit & Veg

DASH

DASH and Mean SBP Change

7 Appel L. N Engl J Med 1997;336:1117-1124

• Effects in African-Americans were nearly double those of Caucasians

Other Findings Related to DASH & BP� In DASH-sodium trial, DASH lowered BP at all levels of sodium intake but DASH + low sodium led to greatest reductions in BP

� (Sacks F, N Engl J Med 2001)

� African-Americans particularly vulnerable to adverse BP effects of low potassium diet

� (Morris RC, Hypertension 1999)

� In IWHS, concordance with DASH (using score) was not associated with lower risk of Htn

� (Folsom AR, AJH 2007)

� WHI emphasizing fruits, veg & whole grains led to modest reductions in SBP & DBP

� (Howard BV, JAMA 2006)

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-6.8-6.2

-8.4

-12

-9.8

-11.2

-14.0

-12.0

-10.0

-8.0

-6.0

-4.0

-2.0

0.0

Mean Change in SBP (mmHg)

Advice only

EST

EST+DASH

Met. Syndrome No Met. Syndrome

SBP Change in Setting of Metabolic Syndrome: (PREMIER Study)

Lien LF et al. Hypertension 2007;50:609-6169

6-month follow up

• In setting of MetS,

DASH diet enhanced

beneficial effect of EST

intervention

• In those without MetS,

the EST intervention &

EST + DASH were

equally effective

No added benefit of DASH compared with EST alone for lipids, insulin resistance or glucose

Why the Inconsistent Results?� Original RCT, well-controlled feeding study-demonstrated efficacy of DASH approach in subjects with low intakes of key nutrients.

� Baseline intakes key nutrients higher in some subsequent studies so effects may be weaker.

� WHI did not emphasize dairy intake. Review (Kris-Etherton) concludes: there is growing evidence that dairy is involved in BP regulation.

� DASH scoring systems equally weight all dietary components and may wash out important dietary effects.

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Long-term Health Effects of Elevated

Blood Pressure Begin Early

-12

-11

-10

-9

-8

-7

-6

-5

-4

-3

-2

-1

0

1

2

End of Rx 3-mo. f/u End of Rx 3-mo. f/u End of Rx 3-mo. f/u

DASH

Routine Care

Post-treatment completers

DASH = 24; RC = 22

3-Month follow-up completers

DASH = 18; RC = 18

Change

DASH vs. Routine Care

Change in BP & BMI in Adolescents with HBP

Couch et al, J Pediatr 2008;152:494-50112

Change in DBP

Change in SBP

Change in BMI

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4

100

102

104

106

108

110

112

114

116

Preschool Diet Elementary Age

Low / Low

Low / High

High / Low

High / High

SBP (mm Hg)

DASH Eating Pattern in Young Children

and Early Adolescent SBP

Moore LL et al Epidemiology 2005:16:4-11

FV / Dairy Intake

Adjusted for age, sex, baseline BP, activity level, and intake of mg & sodium

Low Dairy: <2 servings/day

Low Fruit/Veg: <4 servings/day

13Moore et al. Epidemiology 2005;16:4-11

50

52

54

56

58

60

Preschool Diet Elementary Age

Low / Low

High / Low

Low / High

High / High

DBP (mm Hg)

DASH Eating Pattern in Young Children

and Early Adolescent DBP

Moore LL et al Epidemiology 2005:16:4-11 (FCS)

FV / Dairy Intake

Adjusted for age, sex, baseline BP, activity level, and intake of mg & sodium14

Moore et al. Epidemiology 2005;16:4-11

DASH Eating Pattern and Blood

Pressure in Adolescent Girls

104

105

106

107

108

109

110

9-10 11-12 13-14 15-16 17-18 19-20

SBP (mmHg)

DA<2.5, FV<3 svgs

DA<2.5, FV>=3 svgsDA>=2.5, FV<3 svgs

DA>=2.5, FV>=3 svgs

SPB in Adolescent Girls

59

60

61

62

63

64

65

66

67

9-10 11-12 13-14 15-16 17-18 19-20

DBP (mmHg)

DPB in Adolescent Girls

Models are adjusted for ages, SES, race, activity, TV & height.Data from National Growth & Health Study

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• Both higher dairy groups had lower

SBPs than those with lower dairy intake

• DASH eating pattern group had

lower DBP levels throughout

adolescence

Effect of DASH Diet on Body Fat

Outcomes in Children and Adolescents

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DASH Eating Pattern and BMI in

Adolescent Girls

18

20

22

24

26

28

9-10 11-12 13-14 15-16 17-18 19-20

Age (years)

BMI (kg/m

2)

DA<2.5 & FV<3 svgs/day

DA<2.5 & FV>=3 svgs/day

DA>=2.5 & FV<3 svgs/day

DA>=2.5 & FV>=3 svgs/day

17 Adjusted for age, height, SES, race, activity, & TV watchingNGHS Data

Both higher dairy intake groups had lower BMI levels than those with lower dairy intakes

17

19

21

23

25

27

9 10 11 12 13 14 15 16 17 18 19

Age (yrs)

BMI (kg/m

2)

<2.75

2.75-<3.25

3.25+

BMI Level According to DASH

Adherence Score

Adjusted for age, height, race, socioeconomic status, activity level & tv/video hrs/day.(NGHS)

NGHS

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DASH adherence score modified from Leviton (2009)

DASH Eating Pattern and Waist

Circumference

66

68

70

72

74

76

78

80

9-10 11-12 13-14 15-16 17-18 19-20

Age (years)

Waist Circumference (cm)

DA<2.5 & FV<3 svgs/day

DA<2.5 & FV>=3 svgs/day

DA>=2.5 & FV<3 svgs/day

DA>=2.5 & FV>=3 svgs/day

Adolescent Girls

19 Adjusted for age, height, SES, race, activity, & TV watching

Effect of DASH Diet on

Blood Lipid Levels

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Comparing DASH vs. Fruits/Veg. Diet

Alone on Changes in Lipid Levels

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

TC LDL HDL Trig TC LDL HDL Trig

Mean change (mmol/L)

DASH FV

Obarzanek E, Am J Clin Nutr 2001;74:80-921

DASH: 7% of calories from saturated fat vs. 14% in controls & 13% on FV diet

Subjects were

participants in

original DASH

trial

Does the Effect of DASH on Lipids

Differ by Presence of Inflammation?

-30

-20

-10

0

10

20

30

40

Week 0 Week 4 Week 8 Week 12Treatm

ent Effect (%

)

Low CRP

High CRP

Triglycerides

-25

-20

-15

-10

-5

0

5

10

Week 0 Week 4 Week 8 Week 12

Treatm

ent Effect (%

)

Low CRP

High CRP

Total Cholesterol

-25

-20

-15

-10

-5

0

5

10

Week 0 Week 4 Week 8 Week 12

Treatm

ent Effect (%

)

Low CRP

High CRP

LDL Cholesterol

-25

-20

-15

-10

-5

0

5

10

Week 0 Week 4 Week 8 Week 12

Treatm

ent Effect (%

)

Low CRP

High CRP

HDL Cholesterol

Erlinger et al. Circulation 2003;108:150-15422Data from original DASH-sodium trial

DASH Eating Pattern and LDL in

Adolescent Girls

90

92

94

96

98

100

102

104

106

9-10 11-12 13-14 15-16 17-21

Age (years)

LDL (mg/dL)

DA<2.5, FV<3 svgs/day

DA<2.5, FV>=3 svgs/day

DA>=2.5, FV<3 svgs/day

DA>=2.5, FV>=3 svgs/day

NGHS

NGHS

23Adjusted for age, height, SES, race, activity, & TV watching

DASH Eating Pattern and HDL in

Adolescent Girls

50

51

52

53

54

55

56

57

58

9-10 11-12 13-14 15-16 17-20

Age (years)

HDL (mg/dL)

DA<2.5, FV<3 svgs/day

DA<2.5, FV >=svgs/day

DA>=2.5+, FV<3 svgs/day

DA>=2.5, FV>=3 svgs/day

Adjusted for age, height, SES, race, activity, & TV watching24

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DASH and Diabetes-related OutcomesChanges in Insulin Sensitivity: DASH

vs. Established Diet (PREMIER Study)

1.50

1.70

1.90

2.10

2.30

2.50

2.70

2.90

3.10

3.30

Insulin Sensitivity Index

Advice only

EST w/o DASH

EST + DASH

Baseline 6 Months

Time

Ard et al. Diabetes Care 2004;27:340-34726

After adjusting for baseline differences, DASH group had 35% greater increase in

insulin sensitivity.

Relative Risk of Type 2 Diabetes by

DASH Dietary Score

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

All Whites Blacks/Hispanics

Mod High

Liese et al. Diabetes Care 2009;32:1434-1436

Adjusted for age, sex, education level, race/ethnicity, glucose tolerance, family hx diabetes,

smoking, energy intake, energy expenditure, BMI, insulin sensitivity, and insulin secretion

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Adherence to DASH Plan

Limitations: (a) use of single FFQ, (b) scoring system for DASH

DASH Diet and Bone Health

DASH: high in calcium, potassium, mg, vitamin C, protein

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-30

-20

-10

0

10

20

30

40

Baseline Period 1 Period 2 Period 3

% Change

CTX, DASH

OC, DASH

OC, Control

CTX, Control

Effect of DASH on Markers of Bone

Formation & Resorption

* Lin,P.H., J Nutr 2003; 133:3130-3629

CTX = C-terminal telopeptide of type 1 collagen

OC = osteocalcin

Each sodium period = 30 days

3 sodium intake levels: 50, 100, 150 mmol/d

Summary – DASH in Adults

� In controlled trials, DASH reduces BP, LDL-cholesterol, and markers of bone turnover while improving insulin sensitivity.

� DASH scoring systems show varying results in epi. studies (which may reflect limitations of scoring system). Not know whether some components should be weighted more heavily.

� DASH eating pattern, especially when combined with other lifestyle changes, has beneficial effects on body composition

� Race-specific effects need further study.

� DASH plan likely to reduce risk of developing Htn, CVD, osteoporosis and perhaps diabetes and CHF.

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Summary – DASH for Children� Prospective studies show higher combined intakes of dairy &

FV led to lower gains in SBP & DBP throughout childhood & adolescence

� DASH intervention in adolescents with elevated BP lowered SBP without lowering BMI

� Higher intakes FV & dairy led to lower gains in BMI, % body fat (BIA) & waist circumference, independent of activity

� Higher intakes of FV & dairy led to substantially lower LDL and TC levels, without lowering HDL. No beneficial effects on triglyceride levels.

� Adherence to DASH is very low in African-American teens. Thus data are inadequate to draw conclusions at this time.

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Possible Mechanisms of Effect

� DASH eating pattern may displace other food components

that could have adverse effects

� DASH, especially when combined with other lifestyle changes, may lead to weight loss, thereby benefiting BP,

lipids, insulin sensitivity, and other CVD risk

� DASH may lead to greater adherence

� Simplify the message (fruits, vegetables, dairy)

� Palatability

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Mechanisms of Effect (2)

� Potassium, calcium, magnesium – each of these nutrients has

been found to have anti-hypertensive effects through several possible mechanisms

� Alterations in sodium balance and renal clearance of sodium

� Adverse effects of sodium imbalance on sympathetic nervous system & renin-angiotensin system (e.g., vasoconstriction)

� Stimulation of calcium regulatory hormones (e.g., PTH), thereby affecting vascular resistance

� Effects of calcium on “agouti” gene (expressed in adipose tissue) which stimulates calcium influx into cells

� Fiber and/or glycemic index of DASH foods

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Mechanisms of Effect (3)� Bioactive peptides derived from milk proteins (casein and whey)

inhibit the function of ACE (an enzyme that plays a crucial role in the renin-angiotensin system. Inhibition of the ACE pathway reduces sodium retention, thereby lowering BP

� Higher intake of proteins may promote muscle anabolism or reduce catabolism, thus preserving lean mass under weight loss conditions (reducing BP, insulin resistance)

� Glutamate – primary (vegetable) dietary amino acid may counteract oxidative stress & enhance nitric oxide’s hypotensive effects

� Plant polyphenols (e.g., flavonoids) have anti-oxidant properties that lead to reduced inflammation and oxidative stress (associated with hyperlipidemia). This beneficial effects of FV polyphenols on inflammation & oxidative stress shown even in adolescents. (Holt, JADA, 2009)

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Percent of Adults with Hypertension whose

Diet Resembles DASH Eating Pattern

0

5

10

15

0 1 2 3 4 5 6 7 8 9

NHANES:

1988-1994

DASH Score

0

5

10

15

0 1 2 3 4 5 6 7 8 9

DASH Score

Percent Concordance

NHANES:

1999-2004

Mellen PB, Arch. Intern. Med 2008;168(3):308-314

16% 13%

Before DASH recommendations