The Great American Milk Myth
by Charles R. Attwood, M.D., F.A.A.P.
The mother of a seven-year-old boy handed me a note sent to her by the school dietitian. “Billy’s diet has come to our attention,” it read, “because he no longer drinks milk in the cafeteria.” At my suggestion, he had given up milk because it worsened his asthma and eczema. The note’s concluding words were heavily underlined: “Milk is absolutely necessary for calcium and protein!” I knew the mother was worried and I knew why. Billy’s grandmothers and an aunt had osteoporosis.
Parents who want to reduce saturated fat and animal proteins in the family diet have understandable concerns. They’ve read that both may increase the risk of heart disease and certain cancers but worry about calcium deficiencies if milk is discontinued. I often find it necessary to reassure them that some bowing of their child’s legs may be normal up to the age of three, and is not due to a calcium deficiency. Dental decay, during infancy and early childhood, causes the same concern. But ironically, tooth decay can be caused by too frequent bathing of the teeth with milk.
Why is there so much fear about not drinking milk? The milk myth has been created and perpetuated by the dairy industry’s intense lobbying throughout the lifetimes of most adults. The fact is, during most of our kindergarten and grade school years, nutrition teaching aids were supplied by the National Dairy Council. As a result, Billy and everyone around him, from his parents and teachers, to his doctors, lawyers and Congressional representatives, grew up thinking that milk is wholesome and necessary for strong bones and teeth. Never mind that milk wasn’t consumed before the agricultural revolution 10,000 years ago, and still isn’t by 75% of the world population.
Further confusing the consumer are milk and infant formulas claiming to be fortified with vitamin D, which is necessary for proper calcium absorption. Though vitamin D can be obtained by eating sardines, herring, salmon, tuna, egg yolk, and fish oils, none of these high-fat foods is really necessary. Anyone can get adequate amounts simply by being outside in the sunlight for as little as 10 to 15 minutes three times a week. Disabled children and others who cannot get out in the sun can avoid Vitamin D deficiencies and rickets by taking vitamin D supplements rather than fortified dairy products.
The Protein Puzzle
The true connection between milk and strong bones and teeth isn’t exactly what the dairy industry has been telling us all these years. It’s calcium balance-the relationship between the intake and loss of the mineral-that determines bone density. Good bone density attained by the age of 18- 25 usually lasts a lifetime for people who consume a balanced plant-based diet and remain physically active. The problem with milk and other dairy products is that they are not only rich in calcium but they are also high in protein, which has been shown to create calcium loss through the urinary tract.
A 1994 National Institutes of Health Consensus Conference concluded that calcium balance and bone density depended on the ratio of intake to loss, not on calcium intake alone. This evidence is supported by Dr. Walter Willet of Harvard, who found no relationship between calcium intake and hip fractures. Moreover, Professor T. Colin Campbell, editor of this newsletter, referring to a study covering 16 countries, concluded that “the association between the intake of animal protein and fracture rates appears to be as strong as the association between cigarette smoking and lung cancer.”
Elderly South African Bantu women don’t have osteoporosis, despite having a large calcium drain from nursing an average of 10 children. Their diet contains only about 440 mg of calcium, less than half what Americans consume. It appears they are protected by their low intake of protein (50 g daily, compared with 91 g by Americans). Eskimos, on the other hand, who consume a very high protein diet (250 - 400 g) and far more calcium than Americans (2,000 mg daily), have the highest rate of osteoporosis in the world.
Now, let’s take a new look at milk and dairy products as a calcium source, regardless of their protein content. When calcium is expressed as milligrams per 100 calories instead of milligrams per serving, milk and cheese sink to the bottom of the list and green vegetables rise to the top.
A Better Way to Get Calcium
At first glance, you might be tempted to conclude that you would have to eat huge servings of spinach or turnip greens to get adequate calcium. Not so. If you eat a plant-based diet, generally speaking you’ll get as many total calories as if you ate meat and dairy products. In other words, calorie for calorie, vegetables are better sources of calcium than milk and cheese. It’s the whole meal that counts. Also, consider that a cup of cooked spinach contains about the same amount of calcium as a cup of milk.
Even though we’ve been told that many green vegetables contain oxalic acid, which reduces calcium absorption, this too, has been exaggerated by the dairy lobby. A 1990 report in the American Journal of Clinical Nutrition concluded that greens such as broccoli have high levels of calcium and that calcium in kale is absorbed at least as well as that in milk.
Now it begins to make sense. In cultures like Billy’s, where the most protein is consumed, the calcium requirement for good bone density and protection against osteoporosis may be unattainably high, without supplements.
It’s a Catch- 22 situation. But for the majority of the world population, and among those consuming a plant-based diet in Western countries, calcium requirements for normal bone density are easily obtained without milk or other dairy products. Milk, it now seems clear, is not the solution to poor bone density. To the contrary, it’s part of the problem.
Charles Attwood, M.D., is a physician and writer based in Crowley, Louisiana. He is the author of Dr. Attwood’s Low-Fat Prescription for Kids.