Although prostate cancer is ultimately inevitable if you live long enough, there are many ways to delay its onset or reduce its symptoms:

* Take plenty of exercise. If you have a sedentary job, walking is the best exercise to prevent prostate cancer (Cancer Causes Control, 1998; 9: 11-8). If you develop the disease, keep up your fitness regime. It will slow the cancer down, particularly when combined with a high-fibre, low-fat diet (J Urol, 2001; 166: 1185-9).

* Cut down on dairy products, as calcium may be a problem (see text).

* Drink green tea - often. Regular green tea drinkers have a lower risk of prostate cancer. The Chinese, who consume the most green tea, have the least prostate cancer in the world (Semin Urol Oncol, 1999; 17: 70-6).

* Eat lots of soya-based foods, such as tofu. There is some evidence that the high consumption of soya foods in Japan explains why they have 15 times less prostate cancer than Americans. The active ingredient is genistein, which has been found to inhibit the growth of prostate cancer cells in the laboratory (Am J Clin Nutr, 1999; 70: 439S-50S).

Genistein is also found in red clover. On its own, it has been found to slow BPH and prostate cancer in animals (Prostate Cancer Prostatic Dis, 2002; 5: 16-21). However, the findings of studies on genistein and other isoflavones are conflicting, and there could be adverse effects due to the hormone-like actions of these substances.

* Take saw palmetto (Serenoa repens) as a herbal extract; it’s thought to counteract the hormonal imbalances that may cause prostate problems (Br J Clin Pharmacol, 1984; 18: 461-2). It reduces the symptoms of BPH and cancer, too (Urology, 2001; 58: 960-3).

* Eat lots of tomatoes - preferably cooked, or in products such as ketchup and tomato paste. The active anticancer ingredient is lycopene, a carotenoid that gives tomatoes their red colour. A six-year Harvard study discovered that men who ate tomato-based foods more than 10 times a week had a 50 per cent reduction in prostate cancer risk (J Natl Cancer Inst, 1995; 87: 1767-76).

There’s also new evidence that lycopene supplements (30 mg/day) can shrink prostate tumours even after they have developed (Cancer Epidemiol Biomarkers Prev, 2001; 10: 861-8).

* Take 50 mg of vitamin E and 200 mcg of selenium a day (see text).

* Take a zinc supplement. Cancerous and enlarged prostates contain less zinc than normal prostates (Int Urol Nephrol, 1991; 23: 151-4). A daily supplement has been found to reduce cancer risk by 45 per cent (Cancer Epidemiol Biomarkers Prev, 1999; 8: 887-92).

* Cut down on red meat (J Natl Cancer Inst, 1993; 85: 1571-9).