How much calcium and vitamin D?

A recent article in the New York Times questioned the need for high levels of calcium and vitamin D supplementation that has become the new norm. I have already had patients ask me about this, so I will try to address it here.

I am always in favour of obtaining nutrients the way human beings were designed to get them, which is through food. Calcium and vitamin D are actually quite different types of nutrients, so I will discuss them separately. The main take-home point of this blog is that ultimately we are all unique and the beauty of naturopathic medicine is that as an ND I am able to work with you individually to assess your needs and make a recommendation that is personalized to you as an individual. So ultimately, to figure out how much calcium and vitamin D you should or should not take, talk to your naturopathic doctor!

Calcium

I am asked quite often how much calcium we need, what is the best source, etc… Osteoporosis is far too common in western society and yet we get lots of calcium here too! What’s going on? The short answer is that there is so much more to bone health than just calcium. There are three things to look at with regard to bone health.

First, the raw material needed to create bone. Calcium is just one of many building blocks necessary to make bone but it is definitely not the only one! Magnesium, phosphate, boron, and other minerals are all necessary.

Second, a pile of bricks does not make a house just as lots of materials (calcium and other minerals) do not automatically make bone. Bone has to be built and weight bearing exercise is a key factor to signal our bodies to take those materials and do something with them. When more stress is applied to bone, it becomes stronger. There are also other factors in building bone, such as proper blood flow (yes, bone is living tissue and needs blood!) and other signals like vitamin D (see below!) going on in the body.

Finally, we must prevent our bodies from breaking down bone to use those materials elsewhere. This is another complex area but in a nutshell, if your body needs some calcium to buffer your blood to keep it at the perfect pH level (which keeps you alive, by the way), it will draw this from bones. An acidic environment in our tissues increases the need to use bone to balance pH. And what causes an acidic environment? Stress, lack of sleep, caffeine/alcohol, sugar, dairy, and other acidifying foods…

While dairy groups and marketing boards have done an amazing job convincing people they need to eat a lot of servings of dairy products each day to get enough calcium, there are many other great sources of calcium that most people overlook. One great way is to make bone broth! You can also get calcium from leafy green veggies, nuts and seeds, and many other diverse food sources.

Vitamin D

In the case of vitamin D, our bodies use cholesterol (it’s not all bad!) to make vitamin D when our skin is exposed to the sun. For example, a caucasian person out in summer sun in just a bathing suit until his or her skin just begins to turn pink produces between 10,000 and 50,000IU of vitamin D. Vitamin D is a fat soluble vitamin and can therefore be stored by our bodies so that we can make it through winter off the supply we’ve built up in the summer. Lighter skinned people make more vitamin D from the sun so it’s no surprise that at higher latitudes you find blonder, paler people and near the equator (where there is more direct sun exposure and no long, dark winter) you find darker skinned people. Anyway, before there were ever vitamin D supplements, humans spent much of their time, particularly in the summer, outside and likely made enough vitamin D to last through each winter.

However, this is not the world we live in anymore! Unfortunately most people spend nearly all their time indoors during the day and therefore cannot make vitamin D from sun exposure. This alone is a powerful argument for supplementation, not to mention the greater issue of how our incredibly unnatural lifestyle impacts our health, but that is a topic for another day. In addition, there have been many studies on vitamin D in the past few decades demonstrating how vitamin D impacts so much more than bone health. Vitamin D is in fact a hormone, a key signalling system in the body that can impact all kinds of conditions. There are far too many studies for me to summarize here, but if you want to learn more, you can start with reading at the Vitamin D Council.

So how do you know what to do? Again, the best way to determine if supplementation is right for you and how much to supplement is to see a naturopathic doctor who can assess your unique situation. You can also ask your doctor to run a blood test for 25-hydroxy vitamin D. The province of Ontario has recently put more restrictions on this test because it became so popular but if you have a condition for which vitamin D is important or that puts you at greater risk for deficiency, such as osteoporosis, parathyroid disease, pregnancy, or kidney disease, speak to your doctor about testing your levels.