Some of the answers are woven into articles that I write in this column. Some are addressed directly to the people who ask them. But I receive many more good questions than I am able to provide answers for, questions that a lot of you may have also wondered about but were never able to get a straight answer to.
That’s what this week’s column is about. Following are some of the many questions we’ve received whose answers can help people live healthier and longer lives. This week’s questions deal mainly with food, diet and nutrition.
Q: I switched from caffeinated coffee and tea to decaf, but I’m still running to the bathroom all the time. Why? I thought it was caffeine in the beverages that increased the need to urinate.
A: Caffeine does increase the need to "go" but so do other substances in coffee and tea. Tea, for instance, has a diuretic substance called theophylline, which remains in the brew even after it is decaffeinated. And both coffee and tea contain compounds that stimulate the bladder directly, making it more sensitive to the presence of liquids. Of course, coffee and tea are made almost entirely of water. The more water you drink, the more urine you have. And the more often you need to go to the bathroom!
Q: Is it possible to develop food allergy as an adult?
A: Possible, but not probable. Only a small fraction of food allergy sufferers develop the condition in adulthood. Symptoms include itching or swelling of the lips, tongue, or mouth; hives; cramps, vomiting, or diarrhea; itchiness or tightness in the throat, wheezing, or difficulty in breathing.
Eight foods cause 90 percent of food allergies: Milk, eggs, wheat, peanuts, soy, tree nuts (almonds, walnuts and cashew), fish and shellfish. Adults are more likely than children to have food allergies caused by tree nuts and shellfish, and less likely to be allergic to milk and eggs.
Q: What’s the best time of day to take calcium supplement?
A: If you’re over 60 and you take calcium in the form of calcium carbonate, the most popular formulation for calcium supplements, it’s best to take the pill with a meal. Older people are frequently low in stomach "juices" or acid, but the stomach acid that gets secreted during digestion will help you break down the calcium in the supplement.
Just don’t take the calcium pill at an iron-rich meal or a meal during which you might take a multivitamin containing iron. Calcium competes with iron for uptake from the gut into the body, so it’s better to separate large doses of those two minerals into two separate eating occasions.
Q: I’m trying to get my five-a-day of fruits and vegetables, but I just don’t like vegetables. Can I get away with eating only fruits?
A: If you absolutely cannot stomach vegetables, eating extra fruit will compensate to some degree, but fruits and vegetables are not nutritionally identical. For instance, while both vegetables and fruits have nutrients like vitamins C and A (in the form of beta-carotene), certain healthful phytochemicals (plant chemicals) are present in vegetables alone. Cruciferous vegetables like broccoli, cauliflower, and brussels sprouts, for example, contain a compound called sulforaphane that appears to increase the body’s production of enzymes that ward off cancer-promoting agents. Thus, rather than eliminating vegetables altogether, consider these suggestions for making them more palatable:
• Try relatively bland or sweet-flavored vegetables such as sweet potatoes and carrots.
• Drink your vegetables as juices. They won’t have the fibers of whole vegetables, but they still contain many healthful nutrients.
• Tone down the taste of strong vegetables like cabbage, spinach, and broccoli by topping them with sauce or a little grated cheese. Or cook the vegetables part way and then sauté them in a little olive oil and garlic. Adding some calories in the form of ingredients like cheese or oil can make them much more delicious. (Just be sure to go easier on calories elsewhere, say, dessert.)
Q: I was recently told that my total cholesterol level was over 200 and my "good" HDL too low. I was shocked, since I watch my fat intake and rarely eat meat. Could the reading be off because of something I ate? I didn’t fast before the blood was drawn.
A: It’s not likely. Both total cholesterol and HDL-cholesterol, unlike LDL-cholesterol, can be measured without fasting. Granted, after eating a meal containing fat, HDL levels may drop, but only slightly. Keep in mind your total cholesterol level is determined by more than what you eat. Lifestyle factors such as smoking, stress and your level of physical activity can adversely affect readings. Of course, heredity counts, too.
Q: There seems to be more and more experts coming out against carbohydrate-heavy diets. Is it true that bread and pasta make you fat and that you should avoid them to lose weight?
A: No. In societies where carbohydrates are dietary mainstays, people are relatively thin and illnesses like heart disease and diabetes are not commonplace. Case in point: Okinawa. Traditional rice-centered diets are common there, but obesity is not. So are certain tribes in the Philippines, who have not adopted Western food and lifestyle.
What counts in weight control is calories, no matter where they come from. The proof of this is shown in a 1996 study that evaluated the effects of low-calorie diets containing the same number of calories but widely differing amounts of fats and carbohydrates. The researchers found that it was the caloric intake, not the proportion of calories from carbohydrates or fats, that determined weight loss.
Q: I’ve heard arguments for and against eating red meat. Could you clarify the pros and cons?
A: The debate whether to eat red meat is a classic example of why foods aren’t "good" or "bad". You can eat small portions of red meat every day and still be following a very nutritious food plan (as long as you consume plenty of vegetables, fruits and whole grains). Or you avoid red meat altogether, but be eating a lousy diet with too much fried chicken, ice cream and pastry that contain a lot of saturated fat and too few essential nutrients. The best bet: If you like red meat, limit portion sizes to three or four ounces at a time, three or four times a week. That way, you’ll get to enjoy red meat’s taste and get the benefit of the iron and zinc it contains without "overdosing" on its saturated fat.
Q: Which is it, starve a cold and feed a fever, or the other way around?
A: Neither. Just follow your appetite when a cold or fever strikes for a few days. Going hungry – or stuffed – won’t make the virus or high temperature go away any faster.