Cancer
Dairy products linked to increased risk of prostate cancer
By David Liu, Ph. D.
Apr 19, 2008 - 9:20:51 AM

SATURDAY April 19, 2008 (Foodconsumer.org) -- Japanese researchers have recently conducted an epidemiologic study and confirmed the association between high intake of dairy products and increased risk of prostate cancer.

Kurahashi N from the National Cancer Center in Tokyo, Japan and colleagues found the prostate cancer risk was increased by more than 50 percent in those whose intake of dairy products was in the highest quartile, compared to that for the lowest quartile.

Many epidemiologic studies have reported a positive association between prostate cancer and dairy products. Calcium and saturated fatty acid in the products have been suspected to be the causative agents.

The current study was meant to investigate the association between dairy products, calcium, and saturated fatty acid and risk of prostate cancer in Japan where both intake of the products and the incidence of the cancer were low.

For the study, the researchers followed 43,435 Japanese men aged 45 to 74 for an average 7.5 years.  The participants' dietary habits were surveyed using a validated questionnaire including 138 food items.  During the follow-up, 329 men were diagnosed with prostate cancer.

Dairy consumption was associated with the risk of prostate cancer in a dose-dependent manner.  Those whose consumption of total diary products, milk, and yogurt was in the highest quartiles were 63, 53, and 52 percent more likely to develop prostate cancer, respectively, than those whose consumption was in the lowest quartiles.

There were also statistically significant associations for both calcium and saturated fatty acid, but the magnitude of the associations were attenuated after adjusting for potential confounding factors.

Specifically, those who consumed the highest amounts of myristic acid and palmitic acid were 62 and 53 percent more likely to develop prostate cancer than those who consumed the lowest amounts, respectively.

The researchers concluded that "our results suggest that the intake of dairy products may be associated with an increased risk of prostate cancer."


Source: Cancer Epidemiol Biomarkers Prev. 2008 Apr;17(4):930-937.