10/22/2009
1
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
5
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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10/22/2009
3
-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.
10
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
10/22/2009
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
15
• 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
18
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
33
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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10
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
Recommended
