The effect of dietary approaches to stop hypertension (DASH) on serum inflammatory markers: A systematic review and meta-analysis of randomized trials.

BACKGROUND & AIMS: Dietary approaches to stop hypertension (DASH) diet is associated with improved blood pressure and risk of cardiovascular diseases. It is proposed that DASH might also improve systemic inflammatory markers like highly sensitive C-reactive protein (hs-CRP); however, interventional studies have led to conflicting results. The aim of current systematic review was to summarize results of randomized clinical trials examining the effect of DASH on inflammatory biomarkers. METHODS: Randomized trials which assessed the effect of adherence to DASH diet on the circulating inflammatory biomarkers in adults were identified through searching PubMed, EMBASE, Scopus and Google Scholar up to December 2016. Difference in Mean change and its corresponding standard deviation in inflammatory markers between intervention and control groups were calculated to be used as effect size. Random effects model was used to calculate the summary effects. RESULTS: Seven trials were eligible and six studies with 451 participants were included in the meta-analysis which measured hs-CRP as the biomarker of systemic inflammation. The DASH diet significantly decreased serum hs-CRP levels [mean difference (MD) = -1.01, 95% confidence interval (CI): -1.64, -0.38; I-squared (I2) = 67.7%] compared to usual diets; however, the effect was not significant when it was compared with healthy diets (MD = 0.10 mg/L; 95%CI: -0.16, 0.37; I2 = 94.0%). The reduction in serum hs-CRP levels was greater in trials lasted eight weeks or more. CONCLUSION: Adherence to DASH diet is effective in improving circulating serum inflammatory biomarkers in adults, compared with usual diet; therefore, it could be a valuable strategy to suppress inflammation process.

The effect of dietary approaches to stop hypertension (DASH) diet on weight and body composition in adults: a systematic review and meta-analysis of randomized controlled clinical trials.

BACKGROUND: Dietary approaches to stop hypertension (DASH) diet is rich in foods that are proposed to be inversely associated with obesity. Therefore, DASH might better affect body weight; however, published data are conflicting. OBJECTIVE: To assess the effect of DASH on body weight and composition in adults. METHODS: PubMed, EMBASE, Scopus and Google scholar were searched up to December 2015, for relevant randomized controlled clinical trials. Mean changes in body weight, body mass index (BMI) and waist circumference (WC) were extracted. RESULTS: Thirteen articles (ten for body weight, six for BMI and two for WC) were eligible. Meta-analysis revealed that adults on DASH diet lose more weight (weighted mean difference [WMD] = -1.42 kg, 95% confidence interval [95%CI]: -2.03, -0.82) in 8-24 weeks, BMI (WMD = -0.42 kg m(-2) , 95%CI: -0.64, -0.20) in 8-52 weeks and WC (WMD = -1.05 cm, 95%CI: -1.61, -0.49) in 24 weeks compared with controls. Low caloric DASH led to even more weight reduction when compared with other low-energy diets. In addition, the effect was greater in overweight/obese participants and when compared with typical (Western or population's usual) diets. CONCLUSION: DASH diet is a good choice for weight management particularly for weight reduction in overweight and obese participants.