Heart disease is traditionally thought of as affecting more men than women, but in fact it is the number one killer of women worldwide . A recent study indicates that polyphenols found in grapes can actually reduce certain key risk factors for coronary heart disease in women .Polyphenols, antioxidant phytonutrients such as resveratrol, anthocyanins, catechins, and quercetin, are believed to help the body's cells resist damage by free radicals. The same disease-fighting properties are thought to be delivered by both fresh grapes and red wine. For the study researchers say they used a lyophilized grape powder consisting of 92 percent carbohydrate and rich in flavans, anthocyanins, quercetin, myricetin, kaempferol, and resveratrol. They set out to evaluate the effects of grape polyphenols on key risk factors for coronary heart disease in pre- and post-menopausal women.
In a study involving 24 pre-menopausal women and 20 post-menopausal women researchers assigned to one of two groups the lyophilized grape powder. For the first four-week period, one group consumed 36g of lyophilized grape powder, and the other received a placebo with an equal ratio of fructose and dextrose and energy content similar to the grape powder (554KJ).
AdvertisementAfter a three-week washout, the two groups were switched for a second four-week period. Plasma triglyceride concentrations were reduced by 15 percent in the pre-menopausal women after they had taken the grape powder, and 6 percent in the post-menopausal women. Plasma LDL ('bad') cholesterol and apolipoproteins B and E were also lower with the grape powder, and cholesterol ester transfer protein activity was decreased by around 15 percent.
Although the grape powder did not appear to affect LDL oxidation it was found to reduce whole-body oxidative stress significantly. In a study in 2003 ,female guinea pigs that had had their ovaries removed were used as a model for menopausal women . The guinea pigs were fed either a control diet or a diet containing grape powder for twelve weeks. The results bore similarities to those observed in the human subjects - that is, in the grape powder group plasma triglycerides were 39 per cent lower, very low density lipoprotein (VLDL) cholesterol was 50 per cent lower, phospholipids were 30 per cent lower and concentrations of cholesterol in the aorta were 33 per cent lower. However blood levels of LDL cholesterol concentrations did not differ between groups.