Saturday, April 23, 2011

Cranberry Juice Boosts Heart Health

Drinking cranberry juice may help improve endothelial function and reduce cardiovascular disease (CVD) risk, according to a new study published in the American Journal of Clinical Nutrition.

The findings suggest cranberry juice’s polyphenolic compounds were responsible for reducing carotid femoral pulse wave velocity—a clinically relevant measure of arterial stiffness—suggesting an acute benefit; however, no chronic effect on measures of endothelial vasodilator function was found.

Researchers completed an acute pilot study with no placebo (n=15) and a chronic placebo-controlled crossover study (n=44) that examined the effects of cranberry juice on vascular function in subjects with coronary artery disease.

In the chronic crossover study, subjects with coronary heart disease consumed a research preparation of double-strength cranberry juice (54-percent juice, 835 mg total polyphenols and 94 mg anthocyanins) or a matched placebo beverage (480 mL/d) for four weeks each with a two-week rest period between beverages. Beverage order was randomly assigned and participants refrained from consuming other flavonoid-containing beverages during the study. Vascular function was measured before and after each beverage, with follow-up testing at or after12 hours after consumption of the last beverage. Mean carotid-femoral pulse wave velocity decreased after cranberry juice in contrast with an increase after placebo (P=0.003). Brachial artery flow-mediated dilation, digital pulse amplitude tonometry, blood pressure and carotid-radial pulse wave velocity did not change. In the uncontrolled pilot study, researchers observed improved brachial artery flow-mediated dilation and digital pulse amplitude tonometry ratio four hours after consumption of a single 480-mL portion of cranberry juice.

No comments: