Dairy Products Linked To Increased Risk Of Prostate Cancer

CheeseA high intake of dairy products can increase the risk of prostate cancer by as much as 30% according to a study published in the American Journal of Clinical Nutrition in 2001.

The researchers, based at the Harvard Medical School in Boston, used data from the Physicians’ Health Study which involved more than 20,000 men from the United States who were followed from 1984 to 1995. A positive trend between consumption of dairy products and the risk of developing prostate cancer was found. Those in the highest quintile for dairy product intake (more than 2.5 servings a day) were found to be 34% more likely to develop prostate cancer than those in the lowest quintile (less than 0.5 servings of dairy products a day).

Skim milk appeared to have the greatest effect on prostate cancer risk with those consuming at least one serving a day 32% more likely to develop prostate cancer than those who did not consume skim milk at all.

Calcium intake was also correlated with prostate cancer risk and it is believed that the high calcium levels in most dairy foods was responsible for their effect on prostate cancer. The researchers determined that each 500mg increase in calcium intake per day raised prostate cancer risk by 16%. The research was limited however in that calcium intake from supplements was not taken into account.

It it believed that calcium raises the risk of prostate cancer by reducing the action of a particular form of Vitamin D that is thought to suppress the growth of tumors in the prostate gland.

Doctors caution against reducing calcium intake in order to lower the risk of prostate cancer because of calcium’s ability to prevent the loss of bone density and the onset of osteoporosis. Men in particular however should be careful not to greatly exceed the recommended daily intake (RDA) of calcium through the excessive use of calcium supplements.

The absorption of calcium declines steadily after the age of 50 and for this reason, older adults require higher levels of calcium. The current RDA for calcium is set at 1000mg per day for adults aged between 19 and 50 and 1200mg a day for adults over the age of 50. Diets high in both sodium and protein tend to result in greater losses of calcium through the urine therefore adults looking to reduce their intake of dairy products should consider a reduction in salt and protein intake to help preserve adequate calcium levels.