DEAR DR. DONOHUE: My daughter is 40 years old, and her doctor believes she might have lupus. He has her undergoing blood tests to be sure. Please tell me if lupus is life-threatening. How is it treated? How does a person get it? – E.S.

Lupus is an illness that lies somewhere between common and uncommon. More than 1.4 million North Americans have it, and 90 percent of them are women.

Lupus is disease where the immune system turns on its own tissues. Why is a question that has yet to be answered. The exact cause is not known, but with so many women having it, female hormones are thought to have a hand in its appearance. So are genes. If one identical twin has it, the other is at risk for getting it. Ethnicity is another factor. Blacks come down with it more often than whites do.

Its basis as an immune disease shows up in the blood, where antinuclear antibodies are found. Antinuclear antibodies are highly suggestive of lupus. Those are the blood tests your daughter is going to have.

Lupus strikes many tissues and organs. The skin is one of those tissues. A distinctive lupus skin rash is the butterfly rash. The upper parts of the cheeks redden and are connected by a red band that runs across the bridge of the nose, creating a rash with the silhouette of a butterfly.

Joints – particularly those of the fingers, hands, elbows, knees and ankles – become swollen and painful. Consistently in lupus arthritis, the same joints on both sides of the body are involved – e.g., right wrist and left wrist.

The heart, lungs, kidneys, liver and nervous system may be targets of lupus.

The warehouse of medicines now available for lupus treatment is huge. I won’t mention them all. They have turned around the outlook for lupus patients. Today, after living five years or 10 years with the disease, 90 percent of patients are alive and functioning. More than 70 percent live well past 20 years.

Readers who would like more information on lupus can obtain the pamphlet that deals with lupus and other forms of arthritis. Write to: Dr. Donohue – No. 301, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.50 U.S./$6.50 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: What can you tell me about zinc? I’m taking it to prevent prostate cancer. Is it effective? What is the recommended dose? – T.C.

Zinc is an important mineral with many functions. It lends a hand in repairing injured tissues. It’s essential for normal growth. It might figure into proper functioning of taste and smell senses.

The daily adult dose for men is 11 mg and for women, 8 mg.

Natural sources of zinc include lean meats, poultry, some seafoods and whole grains. Many cereals are fortified with it.

Too much zinc can weaken immunity, lower good cholesterol levels and interfere with copper absorption. Its upper limit has been set at 40 mg/day.

Zinc is promoted as a protection against many illnesses. I don’t know if it truly prevents prostate cancer. A convincing case for its efficacy has yet to be made.

It might slow the onset or progression of macular degeneration, the eye problem that disrupts the vision of so many older people. For macular degeneration prevention, 80 mg of zinc are used along with vitamin C, vitamin E, beta carotene and copper. The doses of these vitamins and minerals are very high, so they should not be taken without your doctor’s supervision.

DEAR DR. DONOHUE: I had a CT scan of my abdomen. It showed a liver cyst. Should I worry? My doctor doesn’t. – E.C.

Single, small liver cysts are common and not an invitation for a visit from the Grim Reaper. Before scans came into existence, we did not realize how common they are.

DEAR DR. DONOHUE: The multivitamin I take contains 5,000 IU of vitamin A. According to an article I read, taking this amount can be dangerous. If I consume any food that contains vitamin A, wouldn’t that put me way over the danger level? – G.L.

DEAR DR. DONOHUE: You wrote about vitamin A in the past. Will you please rewrite it and use milligrams? My vitamin’s label gives its content of vitamin A in milligrams. Thank you. – P.B.

At the risk of overdoing the vitamin A story (I just wrote about it a few weeks back), I’ll have another go at it, and I will use all the vitamin A units – milligrams, micrograms and IU (international units).

Vitamin A is good and necessary for all of us. It preserves eye health and night vision in particular. Every body cell needs it to grow. It bolsters the immune system to fight infections. It promotes healthy skin.

Too much vitamin A can weaken bones by accelerating the daily normal bone resorption that takes place to keep bones fresh and strong. An excess of the vitamin, therefore, can lead to osteoporosis.

An adult woman’s daily vitamin A intake should be 2,330 IU (700 micrograms, 0.7 milligrams). For adult men, the daily recommended intake is 3,000 IU (900 micrograms, 0.9 milligrams).

Pushing the daily dose to more than 5,000 IU (1,500 micrograms, 1.5 milligrams) can edge a person close to a danger zone. Taking 10,000 IU (3,000 micrograms, 3 milligrams) is courting trouble.

If a person takes a vitamin A supplement, then that person has to pay attention to foods rich in vitamin A. For example, 3 ounces of beef liver has 30,000 IU. Other foods to watch are vitamin-A-fortified cereals and dairy products. You can surpass the daily limit occasionally without creating problems. Just don’t make a habit of eating liver (or other vitamin-A-rich foods) by the pound when taking a daily vitamin A tablet.

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.

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