Milk Tied to Hip Fractures…Again
Since 1940, the federal government has subsidized a national school lunch program that includes containers of milk for all children. According to the USDA, "Fluid whole milk is an important component in an adequate diet, being one of the most important sources of calcium and contributing substantially to the protein and vitamin A content of a meal. It is an important part of the school lunch."1
As a nation, we have worshipped milk for a long time, believing it to be crucial in a balanced diet and that if kids drink it, they'll grow up with strong and healthy bones. The USDA recommends that everyone should drink at least three cups of milk a day starting at age nine (that includes adults and elderly people, too). In the teen years, we amass about 95 percent of our bone mineral density for life, and so milk drinking has been considered a significant factor in children's health, particularly important from ages 13-19. Now, though, a new study threatens milk's right to the throne.2 Scientists from the Harvard Medical School have concluded that milk does not necessarily help boys resist bone problems later on. In fact, it might lead to a heightened risk of hip fractures in maturity.3
Nearly 100,000 participants over the age of 50, including 35,000 men and nearly 62,000 women, were asked to recollect their milk-drinking habits during their teen years.4 Then, the participants were tracked for 22 years. During this period, 490 men fractured their hips, as did 1226 women.
"What we found was a little surprising," said head researcher Dr. Diane Feskanich. "Teen milk consumption was associated with a higher fracture risk among men, but not women." Milk drinking had absolutely no effect on hip fractures in women. In other words, its protective effect among women was zero. And among men, milk drinking actually seemed to increase vulnerability to fracture. For each glass of milk the men in the study consumed, the risk of hip fracture went up by nine percent. In other words, men who drank three cups of milk a day had a 27 percent increased hip fracture risk compared to men who didn't drink milk at all.
The scientists say the results don't necessarily mean boys should avoid milk. Rather, they claim that the study may be invalid because it depends on recollection rather than hard evidence of milk-drinking habits. (If that's the problem, the extension of that logic is that girls must have more accurate memories than boys. Actually, some experts claim that boys tend to over-report while women tend to under-report.) Then there's the argument that the results don't really reflect milk-drinking as much as the phenomenon of milk making people grow tall, since taller people typically have a greater risk for fracture. And in fact, the taller milk-drinkers in the study had the highest fracture rate. Finally, some experts postulate that maybe bone density is more of an issue for women than men in terms of hip fracture, whereas for men the big issue is height.
But while the experts focus on why men versus women seem to suffer hip fractures after a youth spent drinking milk, they ignore the elephant in the room. The real question centers on the finding that milk consumption in those critical teen years doesn't seem to prevent hip fracture later on for either gender. We've been told repeatedly that we need the calcium in dairy products in order to build strong bones, and this study certainly doesn't bear that advice out. Dr. Feskanich comments, "It does make you stop and ponder and want to see better evidence for our dietary recommendations."
Critics note that several earlier studies found strong evidence that having milk drinking as a major focus in children's health builds strong bones later on in life. But on the other hand, in 2005, the Physician's Committee for Responsible Medicine published a tradition-shattering report in the journal Pediatrics absolutely dismissing milk. Their report analyzed 58 published studies and concluded, "Under scientific scrutiny, the support for the milk myth crumbles... A clear majority of the studies we examined for this review found no relationship between dairy or dietary calcium intake and measures of bone health…To build strong bones and healthy bodies, children need exercise, sunshine, and a diet rich in fruits and vegetables that helps them maintain a healthy body weight."5
As Jon Barron has pointed out, most of us already take in an excess of calcium, and too much calcium can lead to calcification of soft tissue rather than to bone building--and in fact, can lead to brittle bones. That might explain, at least in part, the results of this study. Jon has pointed out that magnesium is a more important mineral than calcium for increasing bone health. But in any event, beyond the question of whether or not milk actually strengthens bones and is important in a balanced diet, there are plenty of health reasons to avoid dairy products, especially pasteurized non-organic milk and cheeses. Jon has written about the risks associated with dairy, many times. And then, maybe most important of all, we have written before that milk has a high phosphorous content, which tends to make the body very acidic and thus requires a lot of minerals from the body to neutralize it. Ultimately, it takes more calcium from the body to neutralize the phosphorus in dairy than you receive from the dairy in the first place. (This is the same problem we see in heavy drinkers of cola with its high levels of phosphoric acid.)
If you nevertheless worry about getting enough calcium (and magnesium), it's worth noting that kale, spinach, sesame seeds, chia seeds, beans and lentils, and nuts are sources equal to milk, providing bone-building minerals in a far more accessible and easily digestible form.
Myths die hard, and so it will probably be a while before the public obsession with milk as health food goes away. That's even more true because the dairy industry has a vested interest in keeping the myth alive. But the facts speak for themselves. Those countries with the highest rates of dairy consumption, including Finland, Sweden, and the United States, happen to have the highest rates of osteoporosis. The countries in the Mediterranean basin, where dairy consumption is particularly low, have very low rates of osteoporosis.
In an article published on the ABC News site, Dr. Swati Shroff asks, "Could olive oil be the new milk?"6 He's referring to a 2012 study that found that people on the Mediterranean Diet had higher levels of a bone-building protein called osteocalcin. Again, the Mediterranean Diet depends on vegetables, fish, nuts, beans and seeds, as well as olive oil and some grains. These are calcium and magnesium-rich foods that are easily assimilated by the body.
So once again, the lesson is clear. To lower your chances of developing osteoporosis, you'd do well to take a lesson from those countries that actually do have low rates of the disease.
- 1. Gunderson, Gordon W., "National School Lunch Program." USDA Food and Nutrition Service. 21 November 2013. http://www.fns.usda.gov/nslp/history_11
- 2. "How Much Food From the Dairy Group is Needed Daily?" USDA. 21 November 2013/ http://www.choosemyplate.gov/food-groups/dairy-amount.html
- 3. Mozes, Alan. "Drinking Milk as Teens May Not Protect Men's Bones." 19 November 2013. WebMD. 21 November 2013. http://www.webmd.com/osteoporosis/news/20131119/drinking-milk-as-teens-might-not-protect-mens-bones-study-suggests
- 4. Feskanich, Diane, ScD, et al. "Milk Consumption During Teenage Years and Risk of Hip Fractures in Older Adults." 18 November 2013. JAMA Pediatrics. 21 November 2013. http://archpedi.jamanetwork.com/article.aspx?articleid=1769138
- 5. Physicians' Committee for Responsible Medicine. "New Study Shatters Milk Myth." 8 March 2005. http://rense.com/general63/milkmyth.htm
- 6. Schroff, Swati. "Mediterranean Diet May Help Bone Health, Study Suggests." 15 August 2012. ABC News. 21 November 2013. http://abcnews.go.com/blogs/health/2012/08/15/mediterranean-diet-may-improve-bone-health-study-suggests