Ask Dr. H: A folk remedy of dubious benefit

Question: I have been taking apple cider vinegar tablets every day for the past nine months since I read that it can prevent genital warts caused by HPV. So far, it's working. Can you explain how it actually works?

Answer: I think its effectiveness is purely coincidental. Although vinegar has been used for treating medical ailments for thousands of years (the Babylonians around 5000 B.C. first converted wine into vinegar and believed it to have exceptional healing powers), no reliable studies show that vinegar (a weak acid) can benefit your health.

In case you haven't heard, apple cider vinegar is an old folk remedy for obesity, muscle cramps, indigestion, arthritis, cholesterol-lowering, cold/flu symptoms, and cancer prevention. Vinegar has been used to help identify possible genital warts by turning the infected tissue white, but that's not the same as destroying virus-infected tissue with super-cold cryotherapy.

While anecdotal reports hold that people have treated a specific ailment by taking apple cider vinegar, that's not the scientific way of assessing the effectiveness of a medical intervention. You need a "double-blinded" study comparing a treated group against another group receiving a placebo.

Lacking evidence of efficacy, I'd restrict the use of apple cider vinegar to salad dressing.

Q: On a recent trip to the New York area, I ate at the Cheesecake Factory and was surprised to see that they list the calorie information on the menu. I knew it wasn't a place to go if you're on a diet, but everything had a whole lot more calories than I thought. It definitely made me choose more carefully! Why don't all restaurants do that?

A: It definitely gives one pause for thought, doesn't it? In 2008, New York City required restaurant chains to post calorie counts directly on their menus. Other areas like the state of California and the city of Seattle followed suit. In 2012, federal law will require all restaurants with 20 or more locations to post calorie information on their menus. Individual restaurants and smaller chains are encouraged, but not required to comply due to the high cost of food analysis.

With one-third of all adults in the United States considered obese, such efforts are worthwhile.

But does it work? A recent British Medical Journal study on New York's efforts to encourage healthy eating shows that the effort has worked for about one in six customers. On any given visit, customers who looked at calorie counts ordered about 100 fewer calories than those who didn't.

One other result of the law is that restaurants are now offering healthier food alternatives. One "happy" step in the effort to curb childhood obesity is that McDonald's has cut the portion of french fries in its Happy Meal in half and now adds fruit, lowering total calories by 20 percent.

A related study published in the Dec. 15 issue of the American Journal of Public Health found that placing in-store calorie information signs in convenience stores located in lower-income, mainly African American neighborhoods in Baltimore reduced the chance that teens would buy a sugary drink by 40 percent.