Chocolate, Chocolate....and More Chocolate!

4 June 2008

Cocoa, a key ingredient in most chocolate products, is rich in flavonoids - a natural plant substance that has antioxidant properties. Some flavonoids may have anti-inflammatory effects similar to aspirin. Low concentrations of these flavonoids can reduce platelet activity in the blood, thereby lowering the risk of blood clots. In a study of healthy, nonsmoking adults with no history of heart disease, researchers at the University of California, Davis, found that platelet activation was inhibited 2 hours and 6 hours after ingestion of a cocoa-enriched beverage. These results suggest that for healthy people, moderate intake of chocolate over the long-term may inhibit platelet activity and ultimately reduce the risk of heart disease.

New research has shown that chocolate is packed with high-quality polyphenol antioxidants - compounds similar to those found in fruits, vegetables and red wine. Dark chocolate and cocoa powder contain the most polyphenols. Animal studies have shown promising results. In Japan, researchers fed cocoa extract to rabbits and found that it retarded cholesterol oxidation which leads to artery plaque build-up. In another experiment, a phenol compound in cocoa called epicatechin was shown to inhibit the formation of benign skin tumors in mice. However research must still be done to find out if these beneficial substances can be absorbed by the human body.

A Dutch study has compared the levels of antioxidant catechins in chocolate and black tea. It is believed that catechins may play an important role in protection against heart disease, cancer and other health conditions. The highest level of total catechins was found in dark chocolate (four times greater than in tea), with lower levels in milk chocolate and black tea. The types of catechins were found to be different in chocolate compred with tea, but it is not yet understood how the different catechins vary in terms of health benefits (Herbalgram Number 48).

Evidence presented at the March 1999 meeting of the American Chemical Society reveals that coffee is an important source of beneficial antioxidant polyphenols in the American diet, and that cocoa powder surpasses both green tea and garlic as a protective antioxidant food. Coffee has been shown to reduce lipid oxidation by 30% in the blood of hamsters, whilst caffeine has a demonstrable beneficial effect on mood, vigilance, alertness, mental concentration and sense of wellbeing, apparently through its effect on the dopaminergic pathway in the brain. A Swedish study however has shown that coffee drinkers should favour filtered rather than cafetière coffee since the latter appears to raise LDL cholesterol (Herbalgram, No. 47, 1999).

Pregnant women who ate chocolate daily while they were pregnant, gave birth to babies that they rated at 6 months to be more active, more positively reactive (smiling and laughing), and who showed less fear in new situations. Women who rated themselves as more stressed during pregnancy, and who ate little chocolate, rated their children more negatively at 6 months. The Finnish researchers speculate that the effects they observed could result from chemicals in chocolate associated with positive mood being passed on to the baby in the womb. (Early Human Development vol 76, p 139).

Stiff arteries are a predictor of cardiovascular risk, but a Greek study has found that dark chocolate can relax arteries and thus increase the surge of blood ejected from the heart. Separately, a Harvard Medical School study has found that cocoa nearly doubled blood flow to the finger in subjects over 50 years of age. (American Society of Hypertension annual meeting 2004).

Consumption of plain, dark chocolate results in an increase in both the total antioxidant capacity and the (-) epicatechin content of blood plasma. However these effects are markedly reduced when the chocolate is consumed with milk or if milk is incorporated as milk chocolate, since milk appears to interfere with the absorption of antioxidants from chocolate. (Nature 424, 1013, 28 August 2003).

Research into chocolate consumption has suggested that women tend to eat more chocolate when they feel depressed. A new German study into chocolate consumption in men however, indicates that the opposite is true - men eat more chocolate when they feel happy. 48 healthy men were shown film clips designed to induce various emotions including joy, sadness, anger and fear, then gave them a piece of chocolate and asked how much they enjoyed it and whether they wanted more. The more happy and ubeat the men felt, the more they enjoyed the chocolate. (Appetite, 39, 147 - 158, 2002).

Categories: Diet & Lifestyle