Harvard Study Links Dairy Product Consumption to Cancer

The study findings were presented by Dr. Ganmaa Davaasambuu, a scientist at the Harvard School of Public Health. She and her colleagues identified “milk from modern dairy farms” as being extremely high in natural estrogens, the hormones that stoke the fire under such cancers as prostate, testicular, breast and uterine when they are not balanced by progesterone and testosterone.

Dr. Davaasambuu pointed out that cows milked in industrial dairy operations have milk particularly rich in female sex hormones because they are milked for up to 300 days a year. In order for a cow to provide continuous milk production, it must produce a calf once a year. This means that nine months out of every year, a dairy cow is pregnant. As the pregnancy reaches termination, the hormone content of its milk becomes quite high and contains up to 33 times as much of one particular estrogen as does the milk from a non-pregnant cow.

In other societies that depend on cow’s milk, cows are milked for human consumption only five months a year, and when they are pregnant they are milked only in the early stages of their pregnancies, making the hormone content of their milk much lower. Dr. Davaasambuu notes that in the U.S. “The milk we drink today is quite unlike the milk our ancestors were drinking,” which probably did not harm them.

Earlier studies were cited as bearing out her hypothesis that dairy consumption increases risk of some cancers. After compiling and evaluating data from across the globe, Dr. Davaasambuu and her colleagues found that milk and cheese consumption were strongly correlated to the incidence of testicular cancer among men ages 20 to 39. Rates were highest in countries where cheese is a national food, and lowest in countries where it is only a small part of the diet. Of particular interest was the finding that since the Japanese have embraced dairy products, deaths from prostate cancer have risen from near zero to 7 per 100,000 people in just the past few years.

In another study, rats fed milk showed a higher incidence of cancer and development of tumors than those who drank water.

Since about 75 percent of American children under the age of 12 consume dairy products daily and the results of this consumption are not known, Dr. Davaasambuu and colleagues have conducted two pilot studies. One looked at children in Mongolia. After a month of being fed commercial U.S. milk, hormone levels jumped. These scientists have called for long-term studies to determine the importance of this for children’s health.

Dr. Davaasambuu was careful not to jump to conclusions, stating that “milk is a food of great complexity,” providing high levels of nutrients necessary for good health, such as iodine, calcium, magnesium, and conjugated linoleic acid (CLA) that in other research have shown to be protective against many types of cancer including those that are hormone related.

It is disconcerting to think that all the dairy products we have lovingly fed our children may be behind the early development of secondary sex characteristics they are experiencing. And it’s frightening to think that a whole class of foods we have made a mainstay in our diets may be undermining our health. But before we buy into these thoughts, let’s think about balance, the overriding theme of nature:

* Since the hazards of unbalanced estrogen are already well known, this study underscores the importance of keeping all hormones at optimal levels and in perfect balance throughout the lifetime. Whether you are man or woman, having estrogen, progesterone and testosterone at optimal levels and in balance is one of the best interventions you can take against cancer, cardiovascular disease and other degenerative diseases. When hormone levels are as they should be, the body can probably deal with the extra estrogen from dairy products.

* When dairy products play a large part in the diet, there is less fruit and vegetable consumption, yet compounds from fruits and vegetables have been documented to be the primary dietary compounds that protect us from cancer. So keeping the diet in balance is important.

*Getting your dairy products from a local dairy that does not practice such techniques as milking cows 300 days a year will keep estrogen levels in the products lower. If you do not have access to a local dairy, choose dairy products, preferably raw, from a company that raises pastured, grass fed animals. Such products are more expensive up front, but not in the long run when you consider the positive effects on your health of that choice compared to choosing products from factory farm production. Products that balance humane treatment with profit are always a better choice.

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