Strong Bones...Need Milk?

Author: Jocie Antonelli

Bones

Quick—If I asked you what to eat for strong bones, how would you respond? I am betting 9 out of 10 would answer, ”drink milk.” You would say that because we have all been taught since grade school that bones need calcium and dairy products are high in calcium. While both those statements are correct, they aren’t mutually exclusive. In other words, your bones need lots of things to be strong besides calcium, and there are many other foods that contain calcium other than milk. So while calcium is clearly important, there are at least 19 other key nutrients that play a vital role in the health of our bones. Besides calcium, the other nutrients with major roles are vitamin D, vitamin K, and magnesium.

Vitamin D has been getting the attention it deserves in recent years. Many of us have come to know it as the “sunshine vitamin” in that our body will manufacture it after our skin is exposed to the sun. We know it is key to calcium absorption. Without vitamin D, the body can only absorb 10-15% of dietary calcium. With adequate vitamin D, calcium absorption increases to 40 percent. World renowned vitamin D researcher Dr. Michael Holick likes to say, “You can swim in calcium and it will do you absolutely no good unless you have adequate vitamin D.” So getting sun exposure and/or taking vitamin D supplements is key (see a previous post).

Next up is vitamin K. Like vitamin D, it is a fat soluble vitamin (this is one of the reasons we need fat in our diets, so we can absorb the fat soluble vitamins A, D, E, and K). If you have heard anything about vitamin K, it is probably about its essential role in blood clotting. As for bones, it is critical for calcium utilization and regulation. It is also needed to produce a protein called osteocalcin which helps bind calcium to the bone. Low vitamin K status is associated with higher levels of bone turnover and increased fracture risk. Dr. Susan Brown, on her website, BetterBones.org writes,”While you probably have enough vitamin K to provide for normal blood clotting, you most likely do not consume enough vitamin K to allow for optimal bone health.” For optimal bone health, adults need to take in about 1000 mcg of K1 a day. Currently, the average K1 intake in the US is only 75 to 125 mcg! Lastly, let’s talk magnesium. Once again, you can read a previous post to learn more. Overall, and through several mechanisms, magnesium is needed for calcium absorption and bone formation. Most US adults do not consume enough magnesium to form and maintain strong bones.This is why I am a big fan of magnesium supplementation.

Now this is where it can get a little murky. The dairy industry would like you to believe that milk products are the answer for bones. However, the research shows the countries “that consume the most cow’s milk and other dairy products have among the highest rates of osteoporosis and hip fracture in later life." One of the reasons for this is that dairy products are generally acid-forming foods, and when taken in excess, can lead to a blood pH that requires calcium to be leached from the bones in order to alkalize. Then there is the matter of individuals with dairy allergies, dairy intolerances, or straight-up vegans. They aren’t consuming many or any dairy products, yet their bones can be perfectly strong and healthy. How can this be? Well, we know calcium isn’t exclusive to dairy products, it is also found in vegetables, fruits, soy, beans, and small bony fish like canned salmon or anchovies. Secondly, bones are complex structures comprised of and reliant on many more nutrients than just calcium.   So we need a diet with a great deal of variety as well as a steady source of weight bearing exercise.

Balanced Recipe for Strong Bones

  1. Rethink your Calcium Intake. There are many calcium-rich vegetables that do double-duty for the bones by alkalizing the system. Additional choices include beans, legumes, soy, fish, seeds, and nuts.
  2. Get some sun. Our body is designed to need some sun exposure. I am not talking tanning, just 10 to 15 minutes of exposure on arms or legs. Because of the seasons, that isn’t always possible. I recommend vitamin D supplementation year-round in the range of 1000-4000 IU daily.
  3. Increase your intake of vitamin K. Look to consume more kale, spinach, greens, yogurt, and fermented foods.
  4. Magnesium. This underappreciated mineral is high in spinach, almonds, black beans, avocado, yogurt, and bananas.  
  5. Exercise. Make sure you get some weight bearing cardio exercise (i.e. jogging or tennis as opposed to just swimming or elliptical, as well as strength training).
     

References:
Lanou, A. J. (2006). Bone health in children. Bmj,333(7572), 763-764. doi:10.1136/bmj.38996.499410.be
Lundquist, A., & Brown, D. S. (2018, March 09). Home. Retrieved March 09, 2018, from https://www.betterbones.com/
Holick, M. F. (2010). The vitamin D solution. Carlton North, Vic.: Scribe.
Dr. McDougalls Health & Medical Center. (n.d.). Retrieved March 9, 2018, from www.drmcdougall.com

Originally published by Jocie Antonelli at dining.nd.edu on March 21, 2018.