DEAR DR. ROACH: I was a smoker for 65 years, and I got tired of my doctor and everyone else telling me the dangers of smoking. I tried e-cigarettes about two months ago, and I am hooked on them. At first I didn’t like the taste, but now I have gotten used to it. There is a large amount of “smoke” from them, and it is darkening my teeth. What’s your take on this new fad? — S.G. ANSWER: There is no doubt that tobacco has caused vast amounts of suffering and death. The jury is out on the net effect of e-cigarettes, but here are my thoughts. Although e-cigarettes are likely to be much less dangerous than regular cigarettes, there is no doubt in my mind that they are at least potentially harmful to health. On the good side, if they help you quit your smoking habit, they may have a benefit to you. You should use them to help you quit smoking, then ideally quit using them as well. However, there is a bad side, and that is when nonsmokers start using them. Some users don’t think of them as cigarettes at all, calling them “hookah pens,” “vape pens” or other euphemisms. They are simply devices to provide nicotine and flavorings. You used the term “hooked on them,” and they probably do have the potential for addiction.
. DEAR DR. ROACH: Why Lactaid effective? Since it is an enzyme, why isn’t it
denatured by stomach acid, then digested like other proteins? I know from experience that it works, but the biologist and chemist in me doesn’t understand how. — D.M. ANSWER: Lactase, the enzyme in Lactaid, breaks down the milk sugar lactose, which many people can’t digest, into smaller sugars, glucose and galactose. The symptoms of lactose intolerance include bloating, gas and diarrhea. It works best in a slightly acidic environment, but will indeed be digested like other enzymes in the stomach once stomach acid can bring the pH in the stomach to the very acidic range. It works only because it is able to break down sugar faster than it is itself broken down. Clever people have designed lactase in forms that resist stomach acid and are active in the small intestine, which ought to work better. However, Lactaid works well enough for many people intolerant of milk.
. DEAR DR. ROACH: Years ago, I was told that eating raw carrots and fresh spinach improves vision. If this is true, why am I afflicted with
macular degeneration after having eaten these for a long time? I also have taken vitamins to preserve vision for 10 years. Do these have justification? — Anon. ANSWER: Fresh vegetables with beta carotene and certain multivitamins and minerals have been shown to slow the effect of age-related macular degeneration. It may be that you would have gotten macular degeneration both sooner and more severely
had you not had a healthy diet and taken vitamins. Unfortunately, we don’t know of any preventive treatment — nor any treatment once the disease has been diagnosed — that is 100 percent effective. Readers may email questions to ToYourGoodHealth@med.cornell.edu. To view and order health pamphlets, visit www.rbmamall.com, or write to P.O. Box 536475, Orlando, FL 32853-6475.