Consumer Health Journal
Chocolate Shown to Combat Aging
February 2004
By Alison Stewart
Life by chocolate, or death by chocolate? There is an increasing outflow of pro-chocolate PR, and much of the excitement centers around antioxidants. Fruits and vegetables contain antioxidants, which have the ability to temper free radicals, and thereby help to lower the risk of heart disease, some cancers and other age-related maladies. More and more people are trying to bombard their diets with the antioxidant fountain of youth.
Enter chocolate, stage left. Chocolate, derived from the beans of the cacao tree, is brimming with antioxidants, in much higher concentrations than other produce. This could be because chocolate is highly concentrated, undiluted by the water that makes fruits and vegetables so juicy.
How it works: the Biology
Big picture: Although we need oxygen to live, oxygen is dangerous. It's like using dynamite to light a stove. Humans have evolved to breathe oxygen-containing air, but it's a volatile substance. Not surprisingly, plants have opted to avoid oxygen and to release it whenever possible. That could be why trees can live so much longer; their bodies aren't constantly bombarded with destructive oxygen.
According to a USDA article ("Vitamins and Minerals, Free Radicals and Aging" by Jack Saari - link to article), the most popular explanation of aging illness is the "oxidative theory," or "free radical theory." This theory says that, though oxygen is necessary to human life, it is also increasingly harmful as we age.
A natural byproduct of metabolism, oxygen can be transformed into free radicals. Free radicals are atoms or molecules that have an unpaired electron. They are usually very unstable, trying to bind with anything that will give them their missing electron. (source). These free radicals wreak havoc on protein, DNA and fat molecules, upon which our bodies depend.
The USDA article explains that to combat free radical damage, our bodies have antioxidant enzymes. These enzymes weaken over time, however, and the body's defenses can be boosted by the ingestion of antioxidant-containing foods, or foods that contain vitamins that boost antioxidants in the body.
For example, vitamins C and E have been shown to act as antioxidants, which means that they bind with the free radicals, thereby disarming their destructive potential.
Antioxidant foods are rated by their ORAC, or "oxygen radical absorbance capacity," which is a food's ability to calm free radicals. And this brings us back to chocolate.
Dark chocolate, per 100 grams, has twice the ORAC of milk chocolate, four times the ORAC of raisins and about ten times the ORAC of raspberries, according to data (link to data) from the USDA and the Journal of the American Chemical Society.
ORAC per 100 grams
13,120 Dark Chocolate
6,740 Milk Chocolate
5,770 Prunes
2,830 Raisins
2,400 Blueberries
1,770 Kale
980 Brussel Sprouts
739 Red Grapes
400 Corn
390 Eggplant
(source)
Dr. Ronald Prior, a USDA nutrition researcher, has studied the antioxidant potential of chocolate.
"Dark chocolate is going to be on the high end, higher than most fruits and vegetables," Prior said.
He stressed the importance of eating a variety of antioxidant-containing foods, however. "It's the combination that's going to be beneficial," Prior said.
Dark, Milk or White Chocolate?
Dark.
One recent study, "Plasma antioxidants from chocolate" (Nature, 8/03), showed that eating plain, dark chocolate increased antioxidant capacity. These gains, however, were significantly reduced if the chocolate was milk chocolate or consumed with milk. The study concluded that milk may erase the benefits of eating dark chocolate.
Another study, "Chocolate and Blood Pressure in Elderly Individuals with Isolated Systolic Hypertension" (Journal of the American Medical Association, 8/03), focused on white chocolate versus dark chocolate. The study compared 13 men and women, ages 55-64, who had untreated, mild hypertension.
Participants were randomly assigned 14 days of either 90 grams of white chocolate or 90 grams of dark chocolate. Within 10 days of the 14-day experiment, those eating dark chocolate had significantly lowered their blood pressure, while those eating white chocolate had not benefited.
However, the results did not last beyond the chocolate intake; participants' blood pressures returned to the pre-chocolate level within two days of stopping chocolate intake.
http://www.consumerhealthjournal.com/articles/chocolate.htm