This article is more than 5 years old. Information may no longer be current.
DASH diet effective for BP reduction
Click Here to Manage Email Alerts
While many dietary interventions are associated with reductions in BP, the Dietary Approaches to Stop Hypertension diet may product the greatest decline, according to new research published in Hypertension.
Researchers performed a systematic review and meta-analysis of 24 randomized controlled trials covering 23,858 participants that were conducted between January 1990 and March 2015. Their goal was to measure the combined effects of dietary interventions on BP and to determine whether effectiveness varied among the different approaches.
The median age of participants was 45 years. Only 10 studies reported information on race/ethnicity; in those studies, the majority of patients were white.
The combined net effect of dietary intervention on systolic BP and diastolic BP was –3.07 mm Hg (95% CI, –3.85 to–2.30) and –1.81 mm Hg (95% CI, –2.24 to –1.38), respectively. The largest net reduction of –7.62 mm Hg (95% CI, –9.95 to –5.29) for systolic BP and –4.22 mm Hg (95% CI, –5.87 to –2.57) for diastolic BP was observed with the DASH diet.
Other dietary approaches, including low-sodium, low-sodium/high-potassium, low-sodium/low-calorie and low-calorie diets, also produced significant reductions in systolic and diastolic BP. Adherence to the Mediterranean diet, however, was associated with reduced diastolic BP (–1.44 mm Hg [95% CI, –2.11 to –0.76]), but not systolic BP.
In subgroup analyses, those participants with pre-existing hypertension experienced larger net reductions in systolic BP (P = .03) and diastolic BP (P = .02) compared with participants with normal BP. Greater reductions in both net systolic BP (P = .01) and diastolic BP (P = .008) were also observed among participants who were not taking antihypertensive medications compared with those prescribed antihypertensive medications. Another difference of note was smaller net effects observed in groups with follow-up longer than 24 months and in larger-sized trials, according to the researchers. The largest BP reductions were observed in trials that included fewer than 100 participants.
Although the reductions in BP may seem small, “the pooled results were incremental BP reductions experienced by those groups adopting dietary interventions [and] even relatively small reductions in BP can dramatically reduce the incidence of CVD and mortality,” the researchers wrote.
They concluded that while all dietary interventions reduced BP, some, like the DASH diet, were more effective than the others, and suggested that certain approaches should be targeted for specific populations. – by Tracey Romero
Disclosure : The researchers report no relevant financial disclosures.
Perspective
Back to TopRaymond Townsend, MD
The actual DASH diet supplied the study participants with the food, on-site at the study Center for lunch or dinner, on weekdays and with prepared food in coolers when not on-site and over weekends. That has been one of the biggest objections about DASH. From a scientific-rigor standpoint, that was the best way to ensure that the sodium intake was low, and the mix of fruits and veggies and so on was optimal. But, that is not how things are done in the real world. Pundits say that only about 10% to 15% of our daily salt intake is discretionary. To get a real and meaningful reduction in sodium intake requires a DASH approach or a lot of education efforts.
Sadly, what we need most in this area of study is hard outcomes. The Mediterranean diet has hard outcomes; DASH does not. Hard outcomes usually take 3 years minimum to see; when you look, for example, at sustainability of benefit, it wanes over time because people are human and salty, fatty foods are, frankly, quite yummy.
Hypertension drugs lower BP much more and are known to reduce HF, stroke and death. Does a low-salt diet do that? In whom? I do emphasize that BP medications work better when people restrict salt. I tell my hypertension patients to eat their meals at, or from home so they have as much control as possible of mineral and calorie content. I believe exercise is valuable; even if it doesn’t do a wallop on BP, it helps curb appetite and improves HDL, triglycerides and blood glucose levels.
Click Here to Manage Email Alerts