Of all the recent reversals in our thinking about nutrition – the comeback of butter vs. margarine, that caffeine is an antioxidant and health-giving drink, that the white bread you loved as a kid was worthless – none has been more welcome than the discovery that chocolate is good for you. In test after test, the active ingredient in chocolate has proven to be a boon for good health.
There is, however, a catch. Only dark chocolate is healthy. Not milk chocolate, white chocolate or any combination in between. The reason comes down to one key component of the rich snack: flavanols.
Dutch researchers were among the first to investigate the antioxidant power of dark chocolate and cocoa, which contain flavanols similar to those found in red wine and tea. A group of 470 elderly men were divided by how much cocoa-containing food they consumed and researchers tracked them over 15 years. The results, published in 2006, were astonishing—those on the high end of cocoa consumption were half as likely to die from cardiovascular disease as those who consumed the least. They concluded that the increased longevity was due to a slightly, but sustained, lower blood pressure.
More recent studies have shown that dark chocolate improves endurance. The experiment, published in the Journal of Proteome Research, had chocolate-eating lab mice whipping their choco-free buddies on the treadmill. The cocoa compound mice were able to run 50 percent longer and had a 30 percent greater density of leg muscle capillaries, which allowed them to deliver more oxygen to their muscles.
Good For The Heart
The reason that chocolate is so good for you is that the natural compounds found in cocoa and dark chocolate aid the cardiovascular system by improving blood flow and reducing blood pressure. Dark chocolate in particular contains vast amounts of flavanols, which stimulate the production of nitric oxide (a key gas that relaxes and widens arteries) allowing for increased blood flow. These flavanols may also prevent the build-up of plaque that can clog arteries, while its antioxidant properties help neutralize the free radicals in your blood.
Epicatechin, another powerhouse nutrient found in dark chocolate, may also help lower the risk of heart disease, cancer and diabetes. According to Norman Hollenberg, professor of medicine at Harvard Medical School, epicatechin is so important that it should be considered a vitamin. Hollenberg spent years studying the benefits of cocoa drinking. He tracked the Kuna people of Panama, who drink up to 40 cups of cocoa a week, and discovered that they had less than a 10 percent risk of stroke, heart failure, cancer and diabetes—the most common diseases in the Western world. Unfortunately, epicatechin has a bitter taste and is often removed from most commercial cocoas.
Not So Sweet
The same effects do not occur for lighter varieties of chocolate. The milk added to milk chocolate actually interferes with your body’s ability to absorb the flavanol antioxidants. White chocolate is worse, since it contains no cocoa at all and is just a mix of pasteurized milk and sugar.
The other good news is that dark chocolate has a low glycemic index—the measure of a food’s impact on blood sugar levels. This means that eating dark chocolate, unlike other sweet treats, will not cause your blood sugar to spike and then crash. For people at risk for diabetes, the flavanols found in dark chocolate may also help cells to better control blood sugar. Those suffering from diabetes have a condition called insulin resistance, which means the normal amount of insulin in the body no longer works to open cells to accept sugar and provide energy. Flavanols trigger the production of nitric oxide inside cells, which stimulates them to accept sugar again. (Of course the rules of moderation still apply.)
A Healthy Treat
The big question, however, is how much chocolate is good for you. Researchers in Milan, Italy, found that 6.7 grams of chocolate a day will give you the best health benefits. That amounts to one small square of chocolate, with advocates suggesting anywhere between daily to bi-weekly consumption.
The study, published in The Journal of Nutrition, focused on one of the main risk factors of cardiovascular diseases: inflammation. Chronic inflammation is often a precursor to diabetes. The study found that people consuming moderate amounts of dark chocolate regularly had significantly lower levels of C-reactive protein in their blood (meaning they had a lower inflammatory state). Those who ate dark chocolate regularly decreased the risk of cardiovascular disease by one-third in women and one-fourth in men.
A recent study by Swiss researchers found that a significantly higher allowance of dark chocolate—40 grams [1.4 ounces]—could positively impact on stress levels. The study monitored the effects of dark chocolate consumption on highly stressed individuals who were given 40 grams of dark chocolate every day for two weeks. The results suggested that the antioxidants and other beneficial compounds found in dark chocolate reduce stress hormones substantially. That should make you feel better, beyond the happiness produced just by eating chocolate (see sidebar).
Keep in mind, however, that chocolate not only needs to be dark, but high quality and minimally processed to be healthy. Generally speaking, dark, organic chocolate contains the most flavanols, since it is the closest form to raw cocoa. Of course, the darker the chocolate the more bitter it tastes; try to consume one that is at least 50% cocoa if you can’t take the Midnight varieties.
