bigstockphoto_Nursing_Calf_1178148.jpgPart of the joy of drinking raw milk and partaking of other locally-produced and non-processed foods is being more a part of a natural system, a cyclical system that revolves around seasonal changes, old-fashioned grazing, and animal reproduction cycles.

Well, it’s this last point that may create a problem for my raw milk consumption. A friend who knows of my interest in raw milk sent me an article from the current issue of Harvard Magazine, which quotes a Mongolian physician expressing concerns about the natural hormone levels of milk (excluding BGH-fed cows). Her research indicates that much of our milk has high levels of estrogens, which have been implicated in hormone-dependent cancers like those of the prostate, breast, uterus, etc.

This physician became interested in the subject of milk when she noticed differences in dairy practices between her native Mongolia and Westernized countries. In Mongolia, pasture-fed cows are milked only through the first three months of a pregnancy, when hormone levels are still low, while in Westernized countries cows are kept pregnant and lactating 300 days a year. And, indeed, she has found evidence that hormone-based cancers in Japan, which uses Westernized dairy practices, have increased since the 1950s at about the same rate as milk consumption increased.

I wondered when I read this whether the same practices apply to farmers producing raw milk, so I called the New Hampshire farmer who supplies me with my milk. She told me that cows have the same nine-month pregnancy cycle as humans, and she milks through the first seven months of a pregnancy; the last two months the cows get “a rest,” and then after birth the cows begin being milked again. This is all standard practice, she said, whether a farmer is selling milk raw or sending it off to a processing plant for pasteurization.

The cow that has been providing my milk, she said, is currently pregnant and due in September. That means she became pregnant in January, and is currently in her fifth month of pregnancy, well into the “high-hormone” period. This farmer has a second cow, but it is currently in its rest period.

I’m uncertain what to make of this situation. As someone who has had prostate cancer, I’ve been told to avoid consuming anything that would stimulate increased testosterone production. But would estrogen do that? There is a school of thought that recommends increased consumption of soy products for men as a way to reduce prostate cancer risks, because of soy’s natural estrogen. Confusing stuff.

Yet in the case of the raw milk, I’m thinking that maybe the best thing to do is avoid drinking milk produced by cows in the fourth through seventh months of pregnancy. That means I have to start shopping around for raw milk, and inquiring of farmers about the pregnancy status of the cows producing the milk.

Obviously, other people have their own special concerns. Indeed, the Harvard Magazine article quotes the researcher as suggesting that cows in late pregnancy should not be milked or, if they are milked, their milk should be labeled to show it comes from a pregnant cow.

I guess I can’t just assume the natural cycles are always working for me. But the advantage I have as someone buying directly from a farmer I know is that at least I can find out the real situation.