Milk and dairy products provide a steadily increasing share of total daily nutrition worldwide and are a readily available source of protein and calcium. Over 50% of the world’s population consumes milk or dairy products on a daily basis, which now constitutes 30%–50% of their daily calorie intake. Milk has become a staple food in northern Europe only in the last 70 years. Before then, rural milk production was widely prevalent but mainly intended to produce butter and cheese from the sour milk leftovers.
Fertility and Sterility, Volume 106, Issue 6, Pages 1310–1311, November 2016.
Milking Apparatus by pkohler.
Over the last century, cow milk and dairy products have become a major component of daily nutrition worldwide. Public health policies recommend high dairy consumption, of at least two to three dairy servings a day. The escalating cow milk market dictated a profound change in traditional dairy cow farming, and today modern milking continues during most of the gestation period. This strategy results in measurable levels of sex hormones of placental origin in commercially available cow milk. Whether milk-originated steroid hormones have biological significance to human health and reproduction is hotly debated. Dairy products, like other animal-based foods, contain bioactive substances, most of which are present in minute quantities. Several studies have suggested a correlation between high milk consumption and poor sperm quality as well as increased risk of prostate and testicular cancer. Well designed, interventional, properly controlled human studies are urgently needed to uncover the potential effects of such a popular food on human reproduction and health.