DEAR DR. DONOHUE: Excluding exercise other than normal, everyday activities, how many calories does a person have to consume to maintain his or her current weight?

I have seen numerous references to a person’s metabolic rate, but have never seen an explanation of it or the effect of a low or high metabolic rate. Does a person with a high metabolic rate have a higher-than-normal body temperature? – B.M.

Estimations for calorie-burning are all over the place. I can give you a rough estimate. Take it for that – a rough estimate.

Even when we’re doing nothing, the body burns calories. While sleeping, we burn calories. The brain demands lots of them, and it doesn’t have any calorie-storage facility, so the rest of the body – including fat stores – provides calories to the brain. Muscles burn calories even when they’re not in use. That’s an advantage that heavily muscular people have. They’re actively metabolizing even when resting.

To maintain the body in a resting state at its current weight – the basal (resting) metabolic rate – can be approximated for men by multiplying current weight in pounds by 4.5 and then adding 900. That’s the total number of calories needed just to keep things running. For women, the BMR is obtained by multiplying current weight in pounds by 3.2 and adding 800. (For those who use metrics, the formulas are: men, weight times 10 plus 900, and for women, weight times 7 plus 800.)

If a person leads an inactive life, add 25 percent more to the total to give the actual number of calories to keep weight the same. For a very active person, add 50 percent more to the total.

People with higher-than-average metabolic rates burn more calories but don’t have higher body temperatures. The brain’s thermostat keeps body temperature the same for all of us in a number of ways.

DEAR DR. DONOHUE: As a dedicated lap swimmer, I hope you will address an issue that has bothered me for some time. I live in a community with a beautiful indoor lap pool. I have observed people arriving at the pool, undressing poolside and jumping in without showering first. Some people think it is permissible to walk into the center wearing their water aerobic shoes, which they use in the pool, and entering the water with them on.

The previous management was aware of the problem but chose not to do anything about it. The new management needs some help in addressing this public health issue. – R.H.

Your community isn’t into hygiene, I see.

You can turn things around by asking to see the log of your pool’s pH and its chlorine content. If neither is in the proper range, the pool is in danger of being closed and the management is in danger of facing lawsuits when people realize the source of their illnesses.

Go for it. I’ll swim some other place until you get this matter resolved.

DEAR DR. DONOHUE: Can you tell me why some people float in a swimming pool and others, like me, sink like a rock? – W.R.

Please permit a gender-based answer.

Women are less dense than men. Women can take that as applicable to their bodies or their minds. Women, therefore, float; men sink.

Let me remove the gender factor. Heavily muscled, big-boned people don’t have the buoyancy that those with greater fat deposits have. The heavily muscled, big-boned people drop to the bottom. The more roly-poly bob on the surface. This applies to men and women equally.

DEAR DR. DONOHUE: Is there a difference between walking 30 minutes every day or walking 60 minutes every other day? – D.M.

I don’t know. It seems to me that every other day would suffice, but authorities tell us to exercise on most days, if not every day, of the week.

DEAR DR. DONOHUE: Patient L.C., who couldn’t raise his or her blood potassium, might have a magnesium deficit. If this person does, he or she can raise potassium by correcting the lack of magnesium. – W.H.

You’re right. In the face of a magnesium deficit, the kidney has a hard time holding on to potassium. It’s lost in the urine. Raising magnesium, when it needs to be raised, can raise the potassium level, too.

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

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