We’ve all heard that milk “does a body good” but there is an argument that drinking too much milk might not do a body some harm instead. Research finds that elderly Icelandic men who said they recall drinking large quantities of milk during their teenage year are 3 times more likely to receive a diagnosis of advanced prostate cancer compared to more moderate teen milk drinkers. This makes experts wonder if the years of puberty, a time when the prostate matures, may also be a period of increased vulnerability as well.
So far the research into prostate cancer and intake of milk during the teen years have brought mixed results. One found milk drinkers were offered some protection against the disease, whereas the other study saw no relationship at all between milk drinking as a teen and prostate cancer. Both projects were small and couldn’t tell the difference between early and advanced stage tumors.
Yet Iceland offers a unique and perfect natural laboratory. The nation had minimum infrastructure during the beginning of the last century, so those in the central regions lived off the land, including drinking lots of milk produced by farm animals. This drink was uncommon in the seaside villages.
For this research, the team used data on over 2000 men born between the years of 1907 and 1937 who had initially partaken in a study that got going during the 1960s.
During the beginning of the 2000’s, the subjects had provided answers to questions on what they ate during their early and middle life for another project. Among the 463 subjects who remembered having milk infrequently in their teens, just 1% had advanced prostate cancer, or had died from the disease in the 25 years of follow up. The number was 3% among the 1800 men who drank milk every day during their adolescence.
The difference couldn’t be explained away by how often the subjects went to the doctor, their education levels or what they ate. How much milk the men drank did not have a connection to early stage tumors. And intake during the midlife years (most studies focus on these years) also didn’t appear to have an impact.
The team feels their data is strong, and that the findings point out that adolescence is a sensitive period for developing prostate cancer. You can’t make such a claim based on just one study, so more work is called for to confirm these findings, and explore the mechanism behind the association.
We know that humans are the only animals in nature who drink milk after being weaned. We are also alone in drinking the milk of another animal for most of our lives.
No one is suggesting that teen boys limit their consumption of milk during this time. Despite the controversy over drinking too much milk and its benefits, no one should worry about drinking it as it brings lots of important nutrients to the body – an 8 ounce serving puts you well on your way to getting the recommended amount of calcium, riboflavin, high quality protein and other valuable nutrients. Giving your body lots of good, natural nutrients as you grow is a smart step toward staying healthy as an adult.