From cancer beaters to cold cures: the medical myths

FIBRE PREVENTS BOWEL CANCER

A fibre-rich diet has been promoted to protect against bowel cancer since the 1970s. The main evidence was that bowel cancer was almost unknown in Africa where fibre-rich vegetables and grains are the staple diet.

But epidemiological studies have been inconclusive and researchers think sugar rather than the absence of fibre in the gut may be the key factor. A diet high in fibre is still good, preventing heart disease.

VITAMIN C CURES A COLD

Vitamin C is one of the most widely used treatments for colds. Linus Pauling, the chemist and Nobel Prize winner, popularised the idea of huge doses to ward off infections in the 1970s. Sales remain high.

But a review of 55 studies last year by researchers from Australia and Finland found even daily doses of two grams - 30 times above the recommended amount - failed to provide protection.

SPINAL MANIPULATION IS GOOD FOR BACK PAIN

Chiropractors and osteopaths are among the most sought-after practitioners of alternative medicine for ailments ranging from a bad back to asthma. Their numbers have grown to 16,000 since the late 1990s when a register of licensed chiropractors was established in the UK. Charges range up to £350 for a course of 12 treatments.

A review of all major research studies of spinal manipulation conducted between 2000 and 2005, has found the treatment is no use, no better than taking a couple of aspirin with some gentle exercise.

TRANQUILLISERS CAN CURE ANXIETY

In the 1970s, GPs handed out the then new tranquillisers such as Valium to over-stressed patients like Smarties. They were wonder drugs, the first time family doctors had had an answer to stress, and quickly became known as "Mother's little helper".

By 1980, thanks largely to Esther Rantzen's TV show That's Life, it became clear that they were addictive and hundreds of thousands of patients, mainly women, were hooked. Today doctors prescribe them reluctantly.

A TONSILLECTOMY CAN PREVENT INFECTION.

For the post-war generation of children, having your tonsils out was routine. Removal of the glands at the back of the throat was seen as the cure for repeated sore throats and ear infections.

But there was no good evidence to show this was so and surgeons turned to grommets. These were small valves inserted in the ear drums of thousands of children in the 1980s to drain fluid to cure the condition known as glue ear. Again, no good evidence of their effectiveness emerged.

A MASTECTOMY IS THE SAFEST OPTION TO PREVENT THE RETURN OF BREAST CANCER.

Until the 1990s, women with breast cancer who opted to have only the lump removed, rather than the whole breast, were frowned on by surgeons who believed they were putting their long-term survival at risk.

But research since has shown that mastectomy confers no advantage for women with locally advanced disease (but which has not spread to the lymph nodes). Surgery where only the lump is removed has a similar 10-year survival rate.