You won’t always be able to feel it in your bones. Osteoporosis, a condition in which the bones become thin or brittle, often stays well hidden, until a minor fall results in a major injury. A broken hip, perhaps, or broken wrist. Scans can reveal thinning of the bones, but in the NHS they are mainly reserved for people who have already had a fracture or are thought to be at increased risk of one. Private companies, meanwhile, have made use of small, easily transportable scanners in order to offer bone density tests at community venues such as church halls or shopping malls.

There is no doubt that osteoporosis is a serious health problem. One in three women and one in 12 men over the age of 50 are estimated to suffer a fracture due to osteoporosis at some point. Hip fractures can have grave consequences: half of patients are unable to live independently thereafter; one in five dies within six months.

Prevention, of course, is better than cure. Weight-bearing exercises, such as walking or aerobics, can help. Studies have also suggested that strength and balance training can also be effective. In addition, it is important to maintain a reasonable weight (being underweight is a risk factor), and to have a diet with sufficient calcium.

Several medicines are marketed for treating osteoporosis. It is estimated that the main class of drug used, bisphosphonates, has been prescribed more than 225 million times since being launched in the mid-1990s. As several FT readers have told me, these drugs have unpleasant side effects: gastric irritation, nausea, joint pains. So are they worth it?

In one study, women with low bone mass density were given either a placebo or a bisphosphonate. In the former group, 2.2 per cent had a hip fracture over 2.9 years. In the latter group, the rate was 1.1 per cent. Though it is technically correct to say that the risk was halved, the overall risk of having a hip fracture remains small. An excellent Cochrane review on these drugs in postmenopausal women explained the effects in those with near normal bone density taking a bisphosphonate called alendronate: there was no difference in hip fracture, but there was a reduction in spinal fracture, from three in 100 to one in 100.

Alendronate lives in interesting times: a class action has been raised against its manufacturers, Merck, with the complainants asserting that they were not given information about an alleged side effect, osteonecrosis – weakening of the bones – of the jaw. Legal proceedings in New York are ongoing, with Merck in vigorous defence. Whatever the outcome, perhaps prevention really shouldn’t be all about drugs.

Margaret McCartney is a GP in Glasgow.
margaret.mccartney@ft.com

For lively discussion of the latest medical issues go to the FT’s Health Blog