A Question of Health: Making no bones about osteoporosis

MY MOTHER and grandmother have both broken their hips. What can I do to prevent the same thing happening to me? I am a 28-year-old non- smoker with two small children.

Now is the right time for you to think about how to prevent broken bones in later life, because by the time you are in your fifties you are fighting an uphill struggle to keep your bones from becoming thin and brittle. And it is not too early to think about how to ensure that your children do not suffer broken bones when they are old, because poor nutrition in childhood and adolescence is an important risk factor. Most broken hips in elderly people are associated with osteoporosis, which makes bones thin and brittle. Human bones are strongest in the first few decades of life, then begin to deteriorate. You should have a calcium intake of at least 1,200mg a day. Most of this will probably come from dairy products, and you should try to use low-fat products. Regular exercise is very important, and weight-bearing, high-impact exercise is particularly good. Your whole family should get into the habit of exercising at least three times a week. Don't wait until your bones get brittle - by then it is too late.

A BLOOD test has revealed that my thyroid hormone levels are "a little on the low side". I have been offered thyroid supplements, but I do not know if they are really necessary. Will I need to take them for the rest of my life?

The thyroid gland, which sits just below the larynx in the front of the neck, produces a hormone - thyroxine - which is vital for health. Children who do not have adequate thyroxine do not grow properly and their intellectual development can be affected. In adults, the effects are more subtle, but the commonest symptoms are tiredness, weight gain and depression. If thyroxine levels fall, the only way to correct them is to take thyroxine supplements. If a blood test shows that your thyroxine levels are on the low side, or if the levels of another hormone - thyroid stimulating hormone (TSH) - are beginning to rise, you are likely to need to take thyroid supplements for the rest of your life. If the thyroxine levels are borderline, it would be sensible to have a repeat blood test in about six months. But if the levels are deteriorating, the only way to correct them is with supplements.

I HAVE taken 150mg of aspirin every day since suffering a heart attack in 1983. My doctor has now suggested that this can be reduced to 75mg. Will this be any less effective?

A relatively tiny dose of aspirin (75mg seems to be plenty) is very effective in reducing the risk of a second heart attack in people who have already had one. The smaller dose that your doctor has suggested should be just as effective as 150mg, and it is less likely to cause side effects such as indigestion.

Send questions to A Question of Health, `The Independent', 1 Canada Square, Canary Wharf, London E14 5DL; fax 0171-293 2182; or e-mail to health@independent.co.uk Dr Kavalier cannot respond personally to questions