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MegaNatural®-BP grape seed extract benefits adults with metabolic syndrome, study shows


  • MegaNatural®-BP grape seed extract reduces high blood pressure in adults with metabolic syndrome
  • Effective dosage is 150 to 300 mg/day for 4 weeks
  • Mean blood pressure reduction is 11 mmHg (systolic) and 6-7 mmHg (diastolic)


This randomized, double-blind, placebo-controlled was designed to evaluate the ability of MegaNatural®-BP grape seed extract (GSE) on reducing high blood pressure in people with metabolic syndrome.

For this study, researchers randomly assigned 27 men and women, mean age 45-47 years, with metabolic syndrome to one of three treatment groups for 4 weeks: low-dose GSE (150 mg/day), high-dose GSE (300 mg/day), or a placebo. Exclusion criteria included: smokers (abstinence for less than 1 year); clinical evidence of coronary artery, pulmonary, gastrointestinal, or renal disease; and use of prescription medications and vitamin preparations.

Serum lipids and blood glucose were measured at the beginning and end of the study. Blood pressure was recorded using an ambulatory monitoring device at the start of the treatment period and at the end. Mean blood pressure values at baseline for similar between treatment groups: 123/74 mmHg, placebo; 134/83 mmHg; low-dose GSE; 127/78 mmHg; high-dose GSE). The primary end points were the mean daytime systolic and diastolic blood pressures. Secondary end points were changes in serum lipids and oxidized low-density lipoprotein (Ox-LDL).

At the end of 4 weeks, GSE significantly (P<.05) reduced systolic blood pressure (-11 mmHg, on average) and diastolic blood pressure (-6 to -7 mmHg, on average), compared to placebo. The effects of the low- and high-dose GSE treatments were similar. No significant changes in heart rate, serum lipids, or blood glucose values were reported.

While the GSE groups showed a nonsignificant decrease in Ox-LDL compared to the placebo group, the change in Ox-LDL appeared to be inversely related to the baseline level and significant (P<.05) in the high-dose GSE group. The high-dose GSE group also showed a significant (P<.05) increase in total plasma catechin levels.

The authors suggest these beneficial effects are attributed to the unique chemical composition of MegaNatural®-BP GSE, which has a high 94% polyphenol content, is primarily composed of catechin units with an average polymerization of 2.4, and is free of terminal gallate units.

These findings suggest that a daily supplement of MegaNatural®-BP GSE (150 to 300 mg/day) for 4 weeks may offer clinical value to help reduce high blood pressure in patients with metabolic syndrome.


Sivaprakasapillai B, Edirisinghe I, Randolph J, Steinberg F, Kappagoda T. Effect of grape seed extract on blood pressure in subjects with the metabolic syndrome. Metabolism. 2009;58(12):1743-6.

PMID: 19608210