Bone Health: It’s Not All About Calcium

bone healthSeems every time we read about supporting healthy bones we talk about Calcium. “Drink milk for strong bones!” Who hasn’t heard that before? Who hasn’t seen a concerned look from a doctor or pediatrician when you say you or your kid isn’t eating many dairy products? And who hasn’t in some time in their life taken a calcium supplement in hopes of preventing bone loss and osteoporosis?

Thing is, we love our bones. They are pretty cool. They protect our organs, provide structure to our body frame, help us move, and even perform many metabolic functions such as store minerals, help balance the pH in our body, and even store fat in the yellow bone marrow, among other jobs. Yes, bones ones are pretty darn cool. Unfortunately how to protect them, beyond more and more calcium, is not widely publicized. I’m not sure why that is.

You see, we need far more than just calcium to achieve optimal bone health. In 2007 researchers found no correlation between increased calcium consumption and decrease in risk for hip fracture (1). Another study in 2014 showed that increasing milk intake during teenage years did not result in lower hip facture rates as adults (1). These are just a few of the studies showing such correlations. Clearly something is missing. Let’s talk through some of the other, less popular nutrients that are critical for calcium utilization and bone formation.

Vitamin D
Ok, Vitamin D is pretty popular, especially here in Washington State where we just don’t get adequate sunlight to synthesize enough of it. A study conducted in Great Britain, which is at a similar latitude to Washington, showed that Vitamin D deficiency amongst the general population during the Winter and Spring months was especially high (3). There is real cause for concern that some of us are deficient in this important nutrient. Its role is to help Calcium get absorbed from the bloodstream and therefore helps mineralize the bones. That seems pretty important. In other words, you can take loads of Calcium all day long, but without Vitamin D, it might not get where it’s needed.

If you are indeed Vitamin D deficient, what is the best way to correct it? Well, limited sun exposure during the warm months is one way. Supplementation all year, especially during the colder months, is naturally another way. Dosage? Unfortunately theories on dosing run all over the map, with standard intakes recommended at 400IU per day for ages 12 months and under and 600IU/day for kids and adults, up to mega high doses of 50,000IU and higher depending on the situation. Best course of action is to talk with your medical provider about what is appropriate for you.

Vitamin K
This is one under-appreciated nutrient. Most of us may think of it in relation to blood clotting, but it’s also a critical friend to calcium. Vitamin K helps create one of the most abundant proteins in the bone, Osteocalcin. Osteocalcin supports the bone matrix by binding calcium and promoting mineralization. Our bones would be at risk for weakness without it.

There are two forms of Vitamin K, K1 and K2. Vitamin K1 is found in green vegetables and supports healthy blood clotting. Vitamin K2, which is made by bacteria lining the GI tract (partly by converting some K1 into K2), is the form that supports bone health. How do we get enough? Leafy greens and green vegetables, as mentioned above, are great sources of K1. Some of that K1 will get converted to K2 which is the form we want for bone health. Another option is to supplement with K2 which will give a direct dose of the stuff our bones need. If you feel your health is pretty good, especially in terms of digestion and gastrointestinal health, some Vit K food sources daily may be enough. If you question your ability to properly absorb and convert Vit K to its active bone-health form, you may want to consider supplementation.

About 50% of our magnesium is stored in the bones, so this mineral has to be important. Several studies have shown that bone density increases as magnesium intake increases. This is one mineral not to ignore as it also supports a host of other functions in the body. One problem noted in recent years is that our food supply is becoming increasingly deficient in this vital nutrient. As soil supplies become depleted, so also does our food. Therefore it’s becoming harder and harder to know if we are getting enough from sources that are typically high in magnesium. These foods include nuts, beans, whole grains, and green leafy vegetables. The RDA for magnesium in women and men is 310mg per day and 400mg per day, respectively. Thankfully supplement options are abundant if you feel you need a little additional support. One word of advice? Unless you suffer from constipation and need some laxative help, try avoiding Mg+ Oxide and go for another form such as Mg+ Citrate, Mg+ Malate or Mg+ Glycinate which tend to be more readily absorbed.

Last but not least, let’s talk about calcium’s role. It is critically important, as much as I have underplayed it to highlight the role of calcium’s best friends. But truly it is one of the most important players in bone strength. There is roughly 1 kg of Calcium in our bodies and 99% of that resides in the bones. It makes up a mineral complex that provides strength and stability to our entire skeleton. When they say calcium builds strong bones, they aren’t kidding. But as we have talked about throughout this entire article, calcium can’t get into the bones and do its job without its main helpers. This complex interplay between a vast array of nutrients, most of which we talked about here, is what keeps us strong and functioning at our full capacity.

The RDA for adults is roughly 1,000mg per day. BUT, this is dependent on ensuring adequate intake of all the nutrients needed for bone health. Otherwise, as mentioned previously, those 1,000 mg of calcium are not going to be well absorbed. And if they don’t get absorbed? Well, that is when calcium starts roaming for other places to live, like in your blood vessels, in soft tissues, in the kidneys, and excreted in the bowels, sometimes causing constipation.

To get adequate calcium, food sources are your best bet. Obviously dairy is the most touted, but for those of us who are dairy intolerant and dairy sensitive, there are other sources as well. These include beans, salmon, sardines, figs, leafy greens, almonds, chia seeds, tofu, and dairy free products that are fortified with calcium.

Oh wait, one more: Exercise!
How could we adequately talk about bone health without mentioning exercise? You see, the cool things about bones is that they are a living tissue and do respond to external stimuli, like exercise. The more force that is placed upon the bones the more they respond by becoming stronger. This is why weight-bearing exercise is the best form of exercise to give those bones a boost.

Types of weight-bearing exercise? Well, anything that causes impact on the bones counts. Brisk walking, hiking, jumping, dancing, cardio gym classes, stair climbing, team sports, and good ol’ weight training. If you don’t need to do exercise for your weight, at least do it for your bones!

Hopefully you now have a better understanding of the complete package when it comes to bone health. It’s not all about calcium, although its role is certainly vital. I think the real take home message is that a well-balanced, varied diet is key. These nutrients we discussed today, in addition to a host of others, play with each other in very intricate and complex ways to support this thing we call the human body. Rarely does isolating one nutrient alone solve the problem. All these nutrients depend on each other, like friends, to get important jobs done. As you can see it is a complex job, so give your body the tools it needs by eating a varied diet and incorporating daily exercise.


If you have specific concerns about your health, especially pertaining to optimal bone health, don’t hesitate to reach out. It’s never too late to start doing what’s right for your main support system, your bones!

Image courtesy of franky242 /

Danielle VenHuizen

Registered Dietitian, Certified LEAP Therapist