Effects of grape seed extract beverage on blood pressure and metabolic indices in individuals with pre-hypertension: a randomised, double-blinded, two-arm, parallel, placebo-controlled trial

Abstract

The aim of the present study was to test grape seed extract (GSE) as a functional ingredient to lower blood pressure (BP) in individuals with pre-hypertension. A single-centre, randomised, two-arm, double-blinded, placebo-controlled, 12-week, parallel study was conducted in middle-aged adults with pre-hypertension. A total of thirty-six subjects were randomised (1:1) to Placebo (n 18) or GSE (n 18) groups; twentynine of them completed all the protocol-specified procedures (Placebo, n 17; GSE, n 12). Subjects consumed a juice (167 kJ (40 kcal)) containing 0 mg (Placebo) or 300 mg/d GSE (150 mg) twice daily for 6 weeks preceded by a 2-week Placebo run-in and followed by 4-week no-beverage follow-up. Compliance was monitored. BP was measured at screening, 0, 6 and 10 weeks of intervention and blood samples were collected at 0, 3, 6 and 10 weeks of intervention. GSE significantly reduced systolic BP (SBP) by 5·6 % (P = 0·012) and diastolic BP (DBP) by 4·7 % (P = 0·049) after 6 weeks of intervention period, which was significantly different (SBP; P = 0·03) or tended to be different (DBP; P = 0·08) from Placebo. BP returned to baseline after the 4-week discontinuation period of GSE beverage. Subjects with higher initial BP experienced greater BP reduction; nearly double the effect size. Fasting insulin and insulin sensitivity tended to improve after 6 weeks of GSE beverage supplementation (P = 0·09 and 0·07, respectively); no significant changes were observed with fasting plasma lipids, glucose, oxidised LDL, flow-mediated dilation or vascular adhesion molecules. Total plasma phenolic acid concentrations were 1·6 times higher after 6 weeks of GSE v. Placebo. GSE was found to be safe and to improve BP in people with pre-hypertension, supporting the use of GSE as a functional ingredient in a low-energy beverage for BP control.Key words: Grape seed extract: Blood pressure: Pre-hypertension: Endothelial function: Insulin sensitivity: Polyphenols Hypertension is a major risk factor for fatal and non-fatal CVD events (1)(2)(3) . Hypertension may affect >90 % of individuals during their lifetimes (4) . Current estimates indicate that hypertension costs the USA almost $70 billion annually in direct medical expenses (5) . Randomised clinical trials and meta-analyses indicate that blood pressure (BP) reductions lower the risk of myocardial infarction, stroke and other cardiovascular deaths (6,7) . Therefore, adequate control of BP in the healthy range is of enormous individual and public health importance.Pre-hypertension is a condition defined by a systolic BP (SBP) between 120 and 139 mmHg or a measured diastolic BP (DBP) between 80 and 89 mmHg (8) . The Framingham Heart Study showed that the 4-year incidence of hypertension increased between 17·6 and 37·3 % in individuals with pre-hypertension between 35 and 64 years of age (9) . Current medical practice does not treat pre-hypertension per se; however, the importance of lifestyle modifications are emphasised in the Joint National Committee (JNC)-7 and JNC-8, which re...

Oxidative Stress and Hypertensive Diseases

“…56 Likewise a recent study showed that grape seed extract, which contains numerous potential nutrients, was also effective in lowering blood pressure in subjects with pre-hypertension. 57 …”

Treatment of Hypertension with Nutrition and Nutraceutical Supplements: Part 2

“…for six weeks preceded by a two-week placebo run-in and followed by a four-week no-beverage follow-up. 151 GSE significantly reduced SBP by 5.6% (P 5 0.012) and DBP by 4.7% (P 5 0.049). 151 BP returned to baseline after the four-week discontinuation period of the GSE beverage.…”

“…151 GSE significantly reduced SBP by 5.6% (P 5 0.012) and DBP by 4.7% (P 5 0.049). 151 BP returned to baseline after the four-week discontinuation period of the GSE beverage. The higher the initial BP, the greater was the response.…”

“…Grape seed extract (GSE) produces a significant reduction in BP in clinical trials and meta-analyses. [1][2][3][4][147][148][149][150][151] GSE in variable doses and variable amounts of resveratrol was administered to subjects in nine randomized trials-a metaanalysis of 390 subjects-and demonstrated a significant reduction in SBP of 1.54 mmHg (P < 0.02) but no reduction in DBP. 147 A significant reduction in BP of 11/8 mmHg (P < 0.05) occurs with 300 mg/day of GSE in one month.…”

“…150 A single-center, randomized, two-arm, double-blinded, placebo-controlled, 12-week parallel study was conducted in 36 middle-aged adults with pre-hypertension. 151 Subjects consumed a juice containing placebo or 300 mg/day GSE, 150 mg b.i.d. for six weeks preceded by a two-week placebo run-in and followed by a four-week no-beverage follow-up.…”