Prostate Disease (Part Two)
Dr Vernon Coleman
There is a considerable amount of research available proving the existence of links between specific types of food and prostate cancer. Way back in 1982 the National Research Council in the United States of America published a technical report entitled ‘Diet, Nutrition and Cancer’ which showed that diet was probably the single most important factor in the development of cancer, and that there was evidence linking cancers of the breast, colon and prostate to particular foods or types of food. But the evidence linking cancer and food goes back many years before 1982.
For example, since the mid-1970s there has been strong evidence to show a link between a high fat intake and prostate cancer. The National Academy of Sciences in the USA reported some time ago that an American study had shown a correlation between a high fat intake and a high risk for prostate cancer. Studies in 41 countries have shown a high correlation between mortality from prostate cancer and intake of fats, milk and meats (especially beef).
A ten year Japanese study involving 122,261 men aged 40 or older showed ‘an inverse association between daily intake of green and yellow vegetables and mortality from prostate cancer’. (In other words the more green and yellow vegetables you eat the less likely you are to develop prostate cancer – and vice versa.) Another study showed that vegetarian men were less likely to develop prostate cancer.
In 1993 a study of 47,855 men, included in the Medical Research Modernization Committee Report revealed that men who had high fat diets had a relative risk of 1.79 for advanced prostate cancer compared to those on low fat diets. (Meaning that men eating a high fat diet are almost twice as likely to develop prostate cancer as are men on a low fat diet.) The investigators who produced this study found that most animal fats were associated with advanced prostate cancer, but fats from vegetables, dairy products (except butter) and fish were not.
In a paper entitled ‘A Case-Control Study of Prostatic Cancer With Reference to Dietary Habits’ which was published in the journal The Prostate in 1988, a team of authors from the Kyoto University, Kyoto University Hospital and Nagoya City University, all in Japan, and Erasmus University Rotterdam in The Netherlands, reported that in 1950 the incidence of prostatic cancer in Japan had been about 0.4 per 100,000 male members of the population but by 1963 it had increased to 2.0 per 100,000 and by 1975 it had grown to 2.5 per 100,000. Observers had suggested that this increase might be linked to the Westernization of Japanese eating habits. (During recent years the consumption of fat, animal protein, eggs, dairy products and oil have all increased considerably in Japan.) And so these authors studied sufferers from prostatic cancer and patients suffering from benign prostatic hypertrophy (non- cancerous prostate enlargement) in order to identify the risk factors for prostatic cancer. They found that a ‘low daily intake of beta-carotene...were significantly correlated with prostatic cancer development.’ (Carrots and other orange and yellow-orange fruits and vegetables, and dark green, leafy vegetables are excellent sources of beta carotene.)
In an article entitled ‘Cohort Study of Diet, Lifestyle and Prostate Cancer in Adventist Men’, which was published in the journal Cancer in 1989, authors from the Department of Preventive Medicine, Lorna Linda University School of Medicine, Lorna Linda, California, USA reported how they had evaluated the dietary and lifestyle characteristics of approximately 14,000 Seventh-Day Adventist men. The men completed a detailed lifestyle questionnaire in 1976, and were monitored for cancer incidence until the end of 1982. The authors concluded that ‘increasing consumption of beans, lentils and peas, tomatoes, raisins, dates and other dried fruit were all associated with significantly decreased prostate cancer risk.’
In an article entitled ‘A Prospective Study of Dietary Fat and Risk of Prostate Cancer’, which was published in the Journal of the National Cancer Institute in 1993, authors from the Harvard Medical School and Brigham and Women’s Hospital, Boston, Mass, USA, Harvard School of Public Health, Boston, USA and Mayo Medical School, Rochester, Minn., USA pointed out that ‘the strong correlation between national consumption of fat and national rate of mortality from prostate cancer has raised the hypothesis that dietary fat increases the risk of this malignancy.’
By studying information relating to 51,529 American men between the ages of 40 and 75, and sending follow-up questionnaires to the men in 1988 and 1990, the authors examined the relationship of fat consumption to the incidence of advanced prostate cancer and to the total incidence of prostate cancer and found that ‘total fat consumption was directly related to risk of advanced prostate cancer’ and that ‘this association was due primarily to animal fat ...but not vegetable fat. Red meat represented the food group with the strongest positive association with advanced cancer.’
The authors concluded that: ‘The results support the hypothesis that animal fat, especially fat from red meat, is associated with an elevated risk of advanced prostate cancer.’ They also noted that: ‘These findings support recommendations to lower intake of meat to reduce the risk of prostate cancer.’
In an article entitled ‘Risk of death from cancer and ischaemic heart disease in meat and non-meat eaters’ published in the British Medical Journal in 1994, authors from the London School of Hygiene and Tropical Medicine in the UK, the University of Otago, Dunedin, New Zealand and the University of Oxford, UK, investigated the health consequences of a vegetarian diet by examining the 12 year mortality of vegetarians and meat eaters.
The researchers reported that their results confirmed ‘the findings of previous studies that have shown a reduction in all cause, cancer and cardiovascular mortality among people who do not eat meat.’
The researchers showed a ‘roughly 40 per cent reduction in mortality from cancer in vegetarians and fish eaters compared with meat eaters’ and also added that ‘the fact that total mortality was about 20 per cent lower in the non-meat eating group than the meat eaters is perhaps of greatest clinical importance.’
In 1988, in The American Journal of Clinical Nutrition, authors from the Division of Cancer Prevention and Control, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA reported that it had been estimated that 930,000 Americans would develop cancer in a single calendar year and that 472,000 individuals would subsequently die of their cancer.
It was reported that the National Cancer Institute (the NCI), which aims to reduce cancer incidence, morbidity and mortality, ‘believes that the potential for dietary changes to reduce the risk of cancer is considerable and that the existing scientific data provide evidence that is sufficiently consistent to warrant prudent interim dietary guidelines that will promote good health and reduce the risk of some types of cancer.’
The NCI suggested reducing fat intake, increasing fibre intake, including a variety of fruits and vegetables in the daily diet, avoiding obesity, consuming alcoholic beverages in moderation if at all and minimising the consumption of salt-cured, salt-pickled and smoked foods.
The report stated that the NCI believed that if these guidelines were followed there would be a 50 per cent reduction in cancer of the colon and rectum, a 25 per cent reduction in breast cancer and a 15 per cent reduction in cancers of the prostate, endometrium and gallbladder.
Although the evidence showing that fat causes cancer is totally convincing (a United States Surgeon General has advised American citizens that: ‘a comparison of populations indicates that death rates for cancers of the breast, colon and prostate are directly proportional to estimated dietary fat intakes’) there is still a considerable amount of doubt about the mechanism whereby fat causes cancer.
One theory is that carcinogenic chemicals simply dissolve and accumulate in fatty tissues. If this is the case then people who eat animal fats will suffer twice for the chances are high that the fat they are eating already contains dissolved carcinogens.
Despite the lack of clear evidence about exactly how fat causes cancer, the final message is quite clear – to reduce your cancer risk you should make a real effort to cut back your fat intake – and that includes cutting out vegetable fats too.
Incidentally, there is also evidence showing that men who have developed prostate cancer will be more likely to recover if they follow a low fat diet. Men in Hong Kong (where the usual diet is rich in rice and vegetables) are half as likely to have cancerous cells in their prostate glands as are men in, for example, Sweden (where diets are high in dairy products and meat). If cancer strikes men in these two areas the men in Hong Kong are eight times more likely to survive than the men in Sweden. Eight times more likely to survive! It is a disgrace that the medical profession still fails to share this vital information with prostate cancer patients.
In 1999, in Quebec City, researchers followed 384 men with prostate cancer over a five year period. The researchers found that the men who ate most saturated fat (the kind most likely to be found in meat and dairy products) had three times the risk of dying from their cancer, compared to the men who followed a low intake of saturated fat.
In 2002, Dr Dean Ornish presented early work showing that a low fat, vegan diet (together with regular exercise and stress management) has a healing effect on men with prostate cancer.
Other research has also shown that men who have advanced prostate cancer can also benefit from the right sort of diet. One study showed that prostate cancer sufferers who followed a macrobiotic diet (consisting mainly of whole grains, vegetables and legumes and avoiding dairy products and most meats) had an average survival of 228 months, compared to 72 months for a matched group of men who followed their ‘normal’ diet.
Why don’t more men with prostate cancer change their diets?
Perhaps because doctors don’t know these things.
And research has also shown that tomatoes and strawberries can protect against cancer. A nine year study of 47,000 men showed that those who ate lots of tomato-based foods (including tomato based spaghetti sauce and pizzas containing tomato) were much less likely to develop prostate cancer.
Men who eat four servings a week of tomato-based foods (particularly tomato ketchup, canned tomatoes, tomato soup, tomato based spaghetti sauce and the tomato sauce used in preparing pizza) reduce their risk of developing prostate cancer by 20 per cent while men who eat at least ten servings a week of tomato-based foods are up to 45 per cent less likely to develop prostate cancer. The reason is that tomatoes contain good quantities of lycopene, a powerful antioxidant, which helps provide protection against cancer – particularly prostate cancer. Lycopene may also protect against heart disease and other cancers. It is the heat processing which seems to increase the availability of lycopene in tomatoes. So frying tomatoes should also increase their lycopene availability.
Tomatoes are not the only foods to be rich in lycopene. Grapefruit is packed with vitamins (especially vitamin C) and rich in fibre and will help strengthen the immune system. But it is pink grapefruit which contains the lycopene which helps provide protection against cancer (particularly prostate cancer) and heart disease.
NOTE
The condensed essay above is taken from the book `How to conquer health problems between ages 50 and 120’ by Dr Vernon Coleman and Donna Antoinette Coleman. For details of how to purchase a copy of this book (which contains information about scores of disorders affecting those between ages 50 and 120) please CLICK HERE
Copyright Vernon Coleman and Donna Antoinette Coleman July 2025
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