Background: The Dietary Approaches to Stop
Hypertension (DASH) Trial provides critical data on the impact of a specific
diet pattern (low in salt, fat, and processed foods and high in fruit and
vegetables) on blood pressure (BP). The
effect of compliance with a DASH-type diet on BP in a general population sample
is less well defined. We studied
associations between a DASH style diet and BP.
Methods: Cross-sectional data from a study of men and women aged 47 to 73
years (n=2047). Participants
completed a physical examination including three standardised clinical BP
recordings. A sub-sample (n=1187) had ambulatory BP measurements (ABPM). Diet was assessed using a DASH dietary score
constructed from a standard FFQ. Lower scores indicated less healthy
diets. Hypertension was defined as
clinic BP>140/90mmH/on medication; 24-hour ABPM >130/80mmHg.
associations were evident between DASH and systolic BP (SBP). There was a
difference in Clinic SBP of 7.5 mmHg and 5.1 mmHg and a difference in ABPM SBP
of 6.3 mmHg and 5.4 mmHg in men
and women respectively between the highest and lowest DASH quintiles. In fully adjusted multivariate regression
analysis, DASH score was inversely associated with SBP. Clear population differences in SBP were
evident across DASH quintiles.
The observed associations indicate that the findings
are consistent with the hypothesis that adherence to DASH-equivalent diet can
reduce BP at the population level. Public
policy promoting a DASH-style healthy diet could have a significant impact on
population health by reducing average blood pressure in the population.