DEAR DR. DONOHUE: If Fosamax and other “wonder drugs” are so wonderful, why do we have to take calcium and vitamin D to make them work for osteoporosis? I can’t take calcium. It causes me severe constipation, and this includes calcium citrate. – I.W.

ANSWER: All bones, even young, healthy bones, need calcium to stay strong. And calcium needs vitamin D to be absorbed from the digestive tract into the blood. No drug – wonder or not – can fill the roles of calcium and vitamin D.

Bones undergo daily remodeling. One kind of cell, the osteoclast, nibbles on old bone to get rid of worn-out material. Another kind of cell, the osteoblast, immediately steps in and lays down new bone. With age, osteoclast activity increases, and osteoblast activity decreases. Osteoporosis results. Fosamax and related drugs muzzle the action of osteoclasts.

Calcium carbonate is the most widely used calcium supplement. It can cause some users to become constipated. Calcium citrate doesn’t usually constipate, although you are an exception to the rule. There are other forms of calcium – a little harder to find, but available – that might overcome the constipating problem. Calcium lactate and calcium gluconate are two examples.

Why not approach the calcium requirement – 1,200 mg a day – by getting it from food? Dairy products are the richest source. Use low-fat dairy products to avoid putting on weight. One cup of skim milk has 300 mg; 1 ounce of cheese, 200-270; 1 cup of yogurt, 350. Some calcium-fortified cereals contain as much as 1,000 mg in a single bowl. Other sources of calcium include sardines with bones; 3 ounces has 400 mg. Three ounces of salmon with bones has 165. Ten dried figs have 270 mg.

You won’t have a hard time finding all the calcium you need in foods.

DEAR DR. DONOHUE: I sent for your publication about the back more than six weeks ago. As of yet, I have not received it. Will you please attend to this for me? – M.R.

ANSWER: I will gladly attend to it for you, but will you write back? You must include your printed address in the letter itself. Envelopes are often discarded.

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.