DEAR DR. DONOHUE: I read an article of yours about how grilling meat may produce cancer-causing chemicals. I have three young children and a husband who grills like a pro. I would say that 90 percent of our meals are prepared on the grill. Can you please give me more information on this? This article has alarmed my husband and me. – K.B.

ANSWER: It wasn’t my intention to alarm anyone. Too many people alarm us on a daily basis, and most of the time it’s a fuss about nothing. I’ll go over the grilling bit once more. Things are not as bad as you might think.

The heat of a grill on meat produces heterocyclic amines, chemicals that have the potential to cause cancer. Fat dripping on hot coals gives rise to polycyclic aromatic hydrocarbons, another batch of chemicals that can cause cancer. How great a danger exists from these chemicals no one is sure. It’s a theoretical risk. All the same, your family eats too many grilled meals (if it’s meat you’re grilling).

Here are some tips to make grilling safer:

• Choose lean meat, so less fat drops onto the coals.

• Marinate with combinations of vinegar, citrus juices, cider, brown sugar, mustard and vegetable oil. Marinating with half a cup of marinade for every pound of meat cuts the cancer danger by 90 percent.

• Raise the grilling surface up higher than its current position. This cuts back on direct heat to meat.

• Turn the meat often with tongs, not with a fork.

• Precook the meat in a microwave for two minutes, or in the oven.

• Remove all charred or burned parts of the meat.

Almost all this information comes from the American Institute for Cancer Research, which you can access at www.aicr.org. When you reach the site, type “grilling” in the search box.

DEAR DR. DONOHUE: Will you settle an argument between a friend and me? He says that beer dehydrates you. Period. I say that it hydrates you as long as you don’t overdo it. I told him that I believe this because beer is only 5 percent alcohol and the rest is water. He sticks to his position. Who is right? – M.C.

ANSWER: You’re both partly right.

Most beers are 4 percent to 5 percent alcohol. In 12 ounces of beer, there is half an ounce of pure alcohol. The rest is mostly water with a bunch of other ingredients.

All forms of alcohol, beer included, stop the release of ADH, antidiuretic hormone. It’s a hormone that halts the production of urine. Without ADH, therefore, lots of urine is made. When a lot is made, the body loses fluid and becomes slightly dehydrated.

It’s said that it takes 8 ounces of water to make up for every 1.5 ounces of pure alcohol. It would take an additional 8-ounce glass of water to make up for the loss of body water that comes from drinking three 12-ounce cans of beer.

DEAR DR. DONOHUE: A year and a half ago, I had my thyroid gland removed. I take thyroid hormone. I have gained 40 pounds since then. The only way I can keep from gaining any more weight is to starve myself. I have myself on 600 calories a day. I joined a gym and have gone six days a week for two hours each day. I have not lost an ounce. Is there an answer to my problem? – M.C.

ANSWER: Something’s drastically wrong here. Six hundred calories isn’t providing you the nutrition you need, especially if you are working out for two hours in a gym. Go back to your doctor. I bet your dose of thyroid hormone is too low, and that’s the reason you’re gaining weight on so few calories. The doctor can check this with a blood test.

DEAR DR. DONOHUE: I would like your opinion on my granddaughter, a 15-year-old girl, a dancer, who has not yet had a period. – W.G.

ANSWER: The average age for a first period is 12.3. There’s a wide variation to that average. If a girl hasn’t menstruated by 16, then an investigation into what’s causing the delay is begun. Your granddaughter has some time before that investigation in undertaken.

Your granddaughter is a dancer. Is she quite thin? Female dancers and gymnasts prize being on the lean side. A girl has to have a certain amount of body fat to have periods.

If your granddaughter is strictly watching her calories, she would be wise to liberalize her diet a bit. A calorie-deficient diet is often at the bottom of delayed menstruation.

If she’s not deliberately keeping herself thin, then she still has time to menstruate and be considered in the normal range of things. If, at 16, it turns out that she’s not producing enough estrogen to have periods, that’s something that has to be corrected. Estrogen production is needed not only for periods but also for strong bones.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com