Q. We hear so much about antioxidant compounds in chocolate. What about cocoa and chocolate milk?
A. Chocolate's flavonoid compounds are under study not only as antioxidants, but also for other health-protective effects like reducing inflammation and lowering blood pressure. Chocolate and cocoa-related products have highly variable flavonoid content and cocoa content on labels can be tricky to decipher.
Cocoa powder is made up of cocoa bean solids -- which hold the flavonoid compounds -- and cocoa butter. One to two tablespoons of natural cocoa powder provide about the same amount of flavonoids as half an ounce of dark chocolate, which is the amount that studies suggest offer health benefits. However, most widely available cocoa mixes contain cocoa treated with alkali (called Dutch cocoa), which removes most of the flavonoid compounds. Chocolate milk is made with Dutch cocoa, because it mixes with cold liquids better; but that means chocolate milk is not a source of these potentially protective flavonoids.
You may find some gourmet cocoa mixes made with natural (untreated) cocoa, and you can make a more flavonoid-rich drink using natural cocoa plus your own sweetener and milk.
Overall, dark chocolate, which can run from 50 to 90 percent cocoa, is higher in flavonoids and has a more intense flavor than milk chocolate, although milk chocolate does provide some flavonoids, too. White chocolate contains no cocoa bean solids and therefore is not a source of flavonoids. You may see white chocolate labels stating a percent cocoa (or cacao) content, but this is all present in the form of cocoa butter, which does not contain flavonoids.
Q. It seems to be so much harder to avoid weight gain as I've gotten older. Is it true that metabolism slows down as we age? Is there anything to do about it?
A. You're right -- if you eat the same as you did as a young adult, and remain just as active, barring some unusual illness, you will gain weight partly due to slowing metabolism.
Research shows we burn fewer calories as we age because of a combination of decreased physical activity, loss of lean muscle tissue and slower metabolic rate. On average, compared to total calorie needs at age 20, at age 50 you need about 200 fewer calories per day, and at age 65 or 70, about 400 to 500 fewer calories per day.
One way to avoid or reduce age-related weight gain is to reduce calorie consumption -- make "treats" a less common event, reduce portion sizes and don't go back for seconds on anything but vegetables.
The good news is that the reduced amount of calories burned with age can be offset by increasing physical activity. Doing 30 to 60 minutes daily of moderate physical activity -- like brisk walking -- generally burns calories similar to the drop in metabolic rate that occurs. This activity doesn't need to occur all at once, but it needs to be virtually every day and needs to take you beyond an easy stroll.
The really terrific news is that even as this activity is helping avoid weight gain, it exerts powerful metabolic effects independent of weight that help to reduce diabetes and cancer risk.
• Provided by the American Institute for Cancer Research.