Meat Consumption and Prostate Cancer

According to the latest report released by World Health Organization (WHO), it has been estimated that 30% of all cancers in the developing world are associated with high intake of certain dietary agents such as red meat and processed animal proteins. A number of studies have also suggested that lower intake of meat has other favorable effects on the overall health. Here is why:

• The fiber component of red meat is very low. High intake of fiber is required for the maintenance of normal motility of the gut that is associated with periodic excretion of toxic metabolites, chemicals and hazardous waste products from the body. Likewise, low fiber intake (via high meat consumption) delays the excretion of toxins and allows diffusion of wastes across the blood vessels.
• Intake of meat is associated with high serum levels of saturated fats that may increase the risk of cardiovascular dysfunction (atherosclerosis, heart attack and stroke).
• Processed meat is full of carcinogenic chemicals that are capable of altering the genetic material of the different tissues; thereby aggravating the risk of malignant transformation of cells, leading to cancers.

Meat Consumption and Prostate Cancer

The hallmark feature of the prostate cancer is abnormal mitotic division of glandular cells that may alter the normal functioning of prostate and may present as; an enlargement in the overall size of the prostate (that can be appreciated on a rectal examination) and formation of irregular borders. Prostate cancer is one of the leading causes of morbidity and mortality in males of all age groups (though more cases are reported in elderly males). Clinical investigation and extensive research indicates that diet has a very strong influence on the development and progression of prostate malignancy in at-risk males.According to a new report published in Nutrition and Cancer (1) the process of prostate carcinogenesis is mediated by testosterone. Red meat is richly supplied with saturated fats (as discussed earlier). Study indicates that intake of saturated fats can increase the production of testosterone (male hormone) by acting as a hormonal substrate (or raw material for steroid hormones). Persistently high testosterone levels in males are associated with BPH (benign prostate hypertrophy) and possibly prostate cancer. Additionally, other mechanisms that are associated with cancer development and progression are:

• High temperature cooking or prolonged cooking is usually needed for hazard-free consumption of red meat; however, barbequing or frying of red meat is associated with production of aromatic compounds and heterocyclic amines that are known carcinogens (1).
• Grilling and processing meat further promotes the production of free radicals and hazardous chemicals.

Despite the popular notion, intake of excessive quantities of certain types of fish or inadequate meat cooking practices can also lead to prostate malignancy. For example; study conducted by Joshi and associates (2) suggested that:

• Intake of oily fish is more strongly associated with prostate cancer when compared to lean fish
• High temperature cooking (prolonged grilling, broiling or frying) is also linked to the prostate cancer.

Besides meat, other dietary agents that are strongly associated with prostate malignancy are:

• Dairy products due to high content of phytanic acid (3), especially butter and related agents
• Intake of carotenoids and other antioxidants can decrease the risk of prostate cancer.

Researches and Studies Conducted for Meat Consumption and Prostate Cancer

1. The relationship between meat consumption and prostate cancer is studied by the researchers of Harvard University. More than 15000 physicians participated in the study that concluded that high intake of red meat (at least five times or more per week) can aggravate the risk of prostate cancer by 2.5% as compared to those with lower intake of meat (4). In addition
2. A recent study published in the Journal of Human Nutrition and Dietetics (4) assessed the relationship between diet modification and cancer development. The study revealed that intake of low fat diet (red meat and dairy products) with high intake of fresh vegetables and fruits can help in decreasing the risk of prostate cancer.

In conclusion, intake of red meat or oily fish can increase the risk of prostate cancer and more aggressive disease in males; which is why it is highly recommended to decrease the frequency of intake to no more than one serving per week.References:

1. John, E. M., Stern, M. C., Sinha, R., & Koo, J. (2011). Meat consumption, cooking practices, meat mutagens, and risk of prostate cancer. Nutrition and cancer, 63(4), 525-537.
2. Joshi, A. D., John, E. M., Koo, J., Ingles, S. A., & Stern, M. C. (2012). Fish intake, cooking practices, and risk of prostate cancer: results from a multi-ethnic case–control study. Cancer Causes & Control, 23(3), 405-420.
3. Wright, M. E., Bowen, P., Virtamo, J., Albanes, D., & Gann, P. H. (2012). Estimated phytanic acid intake and prostate cancer risk: a prospective cohort study. International Journal of Cancer, 131(6), 1396-1406.
4. Ma, R. L., & Chapman, K. (2009). A systematic review of the effect of diet in prostate cancer prevention and treatment. Journal of human nutrition and dietetics, 22(3), 187-199.