In fact, diets high in vitamins A and E as well as vitamin D all appear to significantly reduce the risk of prostate cancer. Virtually all of the 100 or so surveys of prostate cancer incidence to date have shown this link. To use the jargon, these vitamins, together with the mineral selenium, appear to be powerful ‘chemopreventing agents’ (Can J Urol, 2000; 7: 927-35).

In laboratory tests, these vitamins have been shown to inhibit prostate cancer cell cultures. They’ve also proved able to slow down the progress of the disease in experimental animals infected with human prostate cancer cells. However, such results do not necessarily apply to humans (Urologe A, 2000; 39: 304-8).

In terms of active prevention, most of the research has been into vitamin E and selenium. The first major study on vitamin E was carried out in Finland, where men aged 50-70 years were given 50 mg of vitamin E daily (about three times the Recommended Daily Allowance or RDA) for more than five years.

Compared with a control group of men not given the nutrient, the supplemented group had over 30 per cent fewer diagnoses of prostate cancer and over 40 per cent fewer prostate cancer deaths (J Natl Cancer Inst, 1998; 90: 440-6). Later analyses have slightly modified the original findings, revealing that only men who were initially deficient in vitamin E actually benefited (Urology, 2002; 59 [Suppl 1]: 9-19).

In the first major study on selenium supplementation, which began in 1983 and ran for more than 10 years, 1000 American men were given 200 mcg of selenium a day (three times the RDA of 70 mcg) for an average period of about five years.

The results were remarkable. All of the men in the treatment group showed a massive reduction in the incidence of three major cancers - lung, colon and prostate. The incidence of prostate cancer alone was reduced by more than half (JAMA, 1996; 276: 1957-85).

Since then, a number of similar trials have found, in general, the same results, including one study from the prestigious Harvard Department of Nutrition run by Professor Walter Willett. He and his team found that the higher the level of selenium in the body, the lower the risk of advanced prostate cancer. In specific terms, the risk was reduced by as much as a third.

The herbal approach If you haven’t managed to prevent prostate cancer, and wish to avoid conventional treatments, what can you do?

One answer, until very recently, was a Chinese herbal remedy marketed under the name of PC-Spes (spes is the Latin word for ‘hope’). It’s a formula of eight plants: chrysanthemum, liquorice (Glycyrrhiza glabra), Baikal skullcap (Scutellaria baicalensis), saw palmetto (Serenoa repens), Isatis indigotica, Panax pseudoginseng, Rabdosia rubescens and the root fungus Ganoderma lucidum.

PC-Spes took the world of prostate cancer by storm. From the time it first came onto the market in the USA about six years ago, prostate cancer sufferers turned to it in their thousands - mainly through word of mouth.

The effect it appeared to have on prostate cancer was dramatic. Patients said that it not only reduced the annoying symptoms of the early stages of the cancer, but also the pain of advanced cancer. Men for whom conventional hormone therapy had failed also claimed to derive benefit from this herbal remedy.

A few cancer specialists were sufficiently intrigued to mount some serious scientific studies on PC-Spes.