Non-fat milk linked to prostate cancer

The amount of calcium and vitamin D in the diet appears to have little or no impact on the risk of prostate cancer, but the consumption of low-fat or non-fat milk may increase the risk of early forms of cancer. Dietary calcium and dairy products have been thought to increase the risk of prostate cancer by affecting vitamin D metabolism. Data from several prospective studies have supported an association, but many other studies have failed to establish a link. American researchers analysed data from 82,483 men between the age of 45 and 75 years. The Multiethnic Cohort study was conducted between 1993 and 2002. The participants completed a quantitative food frequency questionnaire and various factors, such as weight, smoking status, and education levels were also noted. During an average follow-up period of 8 years, 4,404 men developed prostate cancer. There was no evidence that calcium or vitamin D from any source increased the risk of prostate cancer. In an overall analysis of food groups, the consumption of dairy products and milk were not associated with prostate cancer risk. Further analysis, however, suggested that low-fat or non-fat milk did increase the risk of localised tumours or non-aggressive tumours, while whole milk decreased this risk. In a similar analysis, American researchers investigated the relationship between calcium, vitamin D and prostate cancer in 293,888 men. The study was conducted between 1995 and 2001. The average follow-up period was 6 years. No link between total or supplemental dietary calcium and the total number of non-advanced prostate cancer cases was found. Total calcium intake was tied to advanced and fatal disease, but both associations fell short of statistical significance. Similar to the first study's findings, skimmed milk was linked with advanced prostate cancer. Calcium from non-dairy food, by contrast, was tied to a reduced risk of non-advanced prostate cancer. The findings do not provide strong support for the hypothesis that calcium and dairy foods increase the risk of prostate cancer. Hence, further larger studies with adequate numbers of advanced and fatal prostate cancers are needed to shed more light on this question.