Healthy Eating

How much weight should a woman gain during pregnancy?

DEAR DOCTOR K: I am pregnant, and my doctor says that I'm gaining too much weight. I trust the doctor, but I've heard that it's normal to gain weight during pregnancy. How much weight should a woman gain?

DEAR READER: It's natural for a woman's appetite to increase during pregnancy. This is nature's way of making sure that she eats enough for herself and her growing baby. All women should gain weight during pregnancy, while eating healthfully and sensibly. But too much weight gain isn't good for a woman or her baby.

Does eating several smaller meals help with weight loss?

DEAR DOCTOR K: Does eating several smaller meals throughout the day rather than three larger meals help with weight loss?

DEAR READER:We know that eating fewer calories is important to losing weight, but there is less agreement on the specifics. Are three meals a day best for weight loss? Or is it better to eat more -- or less -- frequently? We can rule out eating fewer than three times a day. You'll feel hungry, making it more likely that you will overeat and choose less healthy foods when you do eat.

Is watching TV the worst sedentary activity for our health?

DEAR DOCTOR K: Is watching TV worse for your health than any other activities that keep you from being active?

DEAR READER: We know that exercise is good for our health, and that too much inactivity is bad for our health. But does it make sense that watching TV is worse than other sedentary activities? Actually, it may. My colleague Dr. Robert Shmerling is an associate professor of medicine at Harvard Medical School. He noted that a recent study shows watching a lot of TV is worse for your health than other activities that involve long periods of sitting. The study Dr. Shmerling referred to enrolled more than 13,000 young and middle-aged adults. Researchers asked the study subjects how much time they spent watching TV, using a computer and driving.

What’s the difference between a good and bad carbs?

DEAR DOCTOR K: In your column you often distinguish between "good" and "bad" carbohydrates. What makes a carb good or bad?

DEAR READER: Carbohydrates -- carbs -- occur naturally in a variety of foods, from fruits, vegetables and milk, to breads, cereals and legumes. Carbs are also added to many foods, often in the form of sugar. Your digestive system transforms carbs into glucose (blood sugar). They are your body's main source of energy. Whether a carb is "good" or "bad" depends on several factors. Some of the most important are:

How does sugar increase the risk of heart disease?

DEAR DOCTOR K: I've read that sugar increases the risk of heart disease. How does it do that? Also, any advice for those of us with a sweet tooth?

DEAR READER: So far as we know, sugar doesn't directly harm the heart. But it sure indirectly harms the heart, by promoting the following cardiac risk factors -- problems that lead to heart disease: OBESITY: Excess calories contribute to obesity. Added sugar is a major source of excess (and empty) calories. Overweight and obese people are at greater risk for heart problems. Today, we're discovering that the cells containing fat make hormones that travel in the blood and have many harmful effects on the heart.

Is it possible to go off blood pressure medication through diet and exercise?

DEAR DOCTOR K: Is it possible to get off blood pressure-lowering medication through diet and exercise?

DEAR READER: Yes, it is. I've seen many patients commit to lifestyle changes and get off blood-pressure medicines entirely. More often, I've seen that a commitment to a healthier lifestyle allows people to greatly reduce how much medication they take, even though they still need some medicines to control their blood pressure. While many people, myself included, would like to not have to take medicines at all, being able to reduce the dose is a big deal. Many of the side effects of medicines are reduced or eliminated by reducing the dose.

What fish should I avoid while pregnant?

DEAR DOCTOR K: I recently found out that I'm pregnant. I'd like to continue eating fish, but I understand some fish contain mercury, which could be harmful to my baby. What fish should I avoid?

DEAR READER: Fish are a great source of lean protein, and many types are rich in heart-healthy omega-3 fatty acids, which help brain and nerve development and protect the heart. In fact, current dietary guidelines recommend that women who are pregnant eat 12 ounces of seafood a week. But as you noted, some species of fish do contain worrisome amounts of methylmercury. This toxin is especially dangerous to developing brains. High-mercury fish you should avoid during pregnancy include swordfish, shark, king mackerel and tilefish.

Am I getting enough iodine in my diet?

DEAR DOCTOR K: I cook with kosher salt, which doesn't contain iodine. Am I getting enough iodine in my diet? Can I get iodine from other foods?

DEAR READER: Before I answer your question, I'll need to explain a little about the thyroid gland and how it works. The thyroid is a small, butterfly-shaped gland that perches with its wings wrapped around the front of your windpipe, below your voice box. This gland influences the rate at which every cell, tissue and organ in your body functions. It does this primarily by secreting thyroid hormones.

How can I make restaurant meals healthier?

DEAR DOCTOR K: I travel regularly for work, so I have to eat out a lot. Could you give me some strategies to make restaurant meals healthier?

DEAR READER: Eating out can ruin even the healthiest diets. That's because restaurants -- and not just fast-food joints -- tend to overdo the butter, sugar and salt. I spoke to registered dietitian Kathy McManus, director of the Department of Nutrition for Harvard-affiliated Brigham and Women's Hospital. She assured me that you can enjoy a meal (or several) on the road if you follow a few handy tips:

Should I switch to diet soda to help cut down on sugar?

DEAR DOCTOR K: You often advise cutting out sugary soda drinks. Should I switch to diet soda?

DEAR READER: Sugary soda drinks have no place in a healthy diet. Excess sugar leads to weight gain -- and obesity increases the risk of many serious health conditions, including heart disease and Type 2 diabetes. As I always say when giving dietary advice, I'm talking about a regular practice, not an occasional sin. If you like a non-diet (sugary) drink once in a while, enjoy it.