Could this be a chocaholic's dream come true? Research at RMIT University in Melbourne suggests that eating dark chocolate has the potential to reduce the risk factors leading to heart disease.
In a pilot study undertaken by Dr Indu Singh with a small group of volunteers, she found that eating chocolate did have an antioxidant effect by decreasing the adverse effect of free radicals in their blood.
Medical scientist Singh has been studying some of the risk factors that cause heart disease by testing natural dietary supplements rich in antioxidants. She says the results indicate that antioxidant supplements play an important role in maintaining normal blood platelet function, exerting a positive effect on blood lipid profile and improving glucose uptake in healthy people.
Platelets are tiny cells in the blood that help stop bleeding. The blood lipid profile is a group of tests often used to determine the risk of heart disease and typically includes measuring cholesterol levels.
"Antioxidants in foods such as the cocoa in chocolate, or olive leaf extract and vitamin E as gamma-tocopherol, have the potential to combat oxidative stress-induced risks leading to cardiovascular diseases," Singh says.
She explains that as we breathe in oxygen from the air, the oxidation that occurs in the cells of the body generates energy but also produces free radicals. These molecules can damage the cells, and their DNA, but are usually 'mopped up' by the body's own antioxidants before they can cause harm.
Because of stress, or eating fatty foods, not exercising or living in a polluted atmosphere, or even just getting older, the body's antioxidant process becomes more inefficient and free radicals start causing 'oxidative damage'.
This has been implicated in several age-associated illnesses, from heart disease and cancer to Alzheimer's. In the first clinical study with cocoa (dark chocolate is rich in cocoa), Singh found a beneficial effect on the platelets in the blood of the volunteers. But she says chocolate has other unwelcome substances, including sugar, cream and additives.
"Such food is too rich and not so healthy. So we wondered what it was in chocolate that gave it its antioxidant properties and we conducted tests with pure cocoa instead," she says.
In a second trial, the researchers recruited volunteers who regularly exercised as well as others who were mostly sedentary They were split into two groups, one of which took capsules of cocoa and the other swallowed a placebo - a capsule with a non-active substance.
Singh says that when a largely sedentary person occasionally wants to do strenuous exercise, the body produces more free radicals, not fewer. That means regular exercise is better than only exercising in sudden or irregular bursts.
The experiment required the volunteers to ride an exercise bicycle for up to an hour with the rate at which they pedalled being set "according to their level of competence". They were fitted with a mask to measure their oxygen intake and carbon dioxide exhalation, and connected to a timer and another device to record the pulse and heart rate.
Before the experiment began, blood samples were taken and the test subjects given capsules containing cocoa or the placebo and told to take them daily for three weeks. They then returned to do the bicycle test, had another blood sample taken, then rode their bikes and at the end had more of their blood taken.
Singh says the volunteers who regularly exercised did not show a big difference between the proportion of free radicals in their blood before and after the bike ride because it was not high to start with.
Although some improvement was evident after taking the cocoa capsules, the most significant difference occurred with the sedentary group where the proportion of free radicals declined sharply after taking the cocoa capsules.
"We then wanted to see whether it was something else causing the effect than just the cocoa," Singh says. "So we looked at other antioxidants that might be useful in countering oxidative stress and preventing or reducing the incidence of cardiovascular disease."
Further experiments were conducted using olive leaf extract with another group of volunteers but using the same testing regime. The results were similar to those with cocoa, just as they were with a third series of experiments using vitamin E capsules in form of gamma tocopherol.
Singh says she was particularly interested in antioxidants that occur in a normal diet. So she ran the vitamin E experiment with gamma tocapherol, the most common form of vitamin E found in a normal diet.
Vitamin E exists in different forms called alpha, gamma and delta tocapherol but that sold in supermarkets or pharmacies is usually alpha tocapherol. This is not found as much in the food we eat as is gamma tocopherol, which occurs in foods such as nuts and some oils.
"Healthy eating and regular exercise could help you lower your risk of developing heart disease," Singh says. "That is, if the diet includes good amounts of olive oil, nuts and green leafy vegetables - and some high-quality dark chocolate!"
This article is taken from- http://www.universityworldnews.com/article.php?story=20101105220725375
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