Don't throw out your calcium supplements yet
Originally published in the Kingston Whig-Standard Many women have come through my doors lately who have been taken off their calcium supplements by their family doctors. After taking them faithfully for many years, women are being told that calcium supplements will increase their risk of having a heart attack. (And many of them developed osteoporosis despite the years of loyal supplementation).
I think this about-face is too abrupt and extreme.
A more recent review of calcium supplementation did not get the media attention that it deserved, in my opinion. This review re-analyzed the same data that appeared to show that calcium supplements are dangerous, plus some other data, including over 93,000 postmenopausal women in total. This review concluded that there is very little evidence to suggest that calcium supplementation increases the risk of heart attack.
There is also some research showing that calcium intake helps maintain normal blood pressure, which is good for the heart! High calcium intake also seems to be associated with having a normal weight — another factor that is good for the heart.
As always in science, more research is necessary. But what should women be doing in the meantime, while we want to keep our bones and our hearts healthy?
Here is what I recommend to my patients.
1. Prioritize dietary sources of calcium: The recommended upper limit for calcium intake is 2000 mg per day. I recommend aiming for 400 mg of calcium each day. Dairy products, of course, are excellent sources of calcium. One cubic inch of cheddar cheese has approximately 120 mg of calcium in it. Tahini, a paste made from sesame seeds, is the highest plant-based source available. One tablespoon of tahini has about 70 mg of calcium in it.
2. Take a smaller supplemental dose: Supplementing at 1500 mg per day is much too high. I recommend taking no more than 500 mg of calcium from supplemental sources. I should note that these lower doses have not been shown to improve bone mineral density in studies.
3. Take a good calcium: The most common form of calcium found in supplements is calcium carbonate. This calcium is also found in antacids, because it neutralizes stomach acid. Minerals require acidity for maximum absorption, so I do not favour this form of calcium. Also, this form seems to cause more adverse effects like constipation. Calcium citrate is another common form of calcium supplement, that is better-absorbed than carbonate. What I recommend most often is microcrystalline hydroxyapatite, which contains calcium and some other minerals. There is a small amount of research indicating that this might be the most effective form of calcium for increasing bone mineral density.
4. Take cofactors: Fat soluble vitamins D3 and K2 are necessary for the proper usage of calcium. They can both be found in fats from animals that have eaten grass, but it is quite difficult to source animal products from animals that have eaten grass, so I recommend supplementing these vitamins. Both D3 and K2 can be found as capsules or tablets. If you are taking them in this form, take them with food that has fat in it to promote their absorption.
5. Signal your body to put the calcium into your bones by exercising: The more I read about exercise, the more I come to see it as a tonic for all the metabolic processes that occur with the body. When it comes to calcium, resistance exercise (like weight-lifting) signals the body to put calcium into the bones.
The pace of medical research is so rapid that none of us has the time to keep up with it on a constant basis. Unfortunately, the media tends to cover only the most dramatic findings, generating over-reaction and sometimes presenting an un-balanced viewpoint.
Whole foods are always the first place to start when you want to have good health, but there are many times when supplements are a good addition.