How Strong Are Your Bones?
It’s no secret that calcium is the essential mineral required for strong, healthy bones. North Americans consume more dairy than any other country on the planet, with the exception of India. The women in our country have been consuming an average of 2 pounds of milk each day for the better part of their lives. Why, then, is osteoporosis and bone degeneration so prevalent in North American society?
The answer to this is not clear, but there are various theories.
One thought is the role Vitamin D plays with respect to our bodies ability to absorb calcium. Vitamin D is produced in the skin of vertebrates after exposure to ultraviolet B light and is necessary for the proper absorption and assimilation of calcium. It is recommended that our skin is exposed to 30 minutes of direct sunlight each day to produce sufficient amounts of Vitamin D. However, herein lies the problem. Not everyone has the same type of skin. Some skin is oily, some is dry, some is fair, some is dark. And to make matters worse, the depletion of the o-zone has raised significant concerns about the potentially hazardous effect of the sun. So the majority of us slather on layers of sunblock to protect ourselves. Does this mean we are not able to get adequate amounts of UV-B to form the Vitamin D that we need? Unfortunately this is not something I can answer.
Another train of thought is the amount of protein and phosphorous our culture consumes. We live in a society in which eating mass amounts of meat and acidic foods is commonplace. I am not saying we should stop eating meat. On the contrary, I believe good quality, organic, free range meat has very important health benefits. However, I also believe that North Americans eat far too much meat, and extremely poor quality at that. An excessive amount of protein promotes calcium loss through our urine. There are many studies throughout the world which actually show that vegetarians typically have healthier, stronger, more dense bones than most meat-eaters.
Phosphorus (in soda, milk and much more) binds with the calcium rendering it unabsorbable by our bodies. That’s right, the milk we drink contains phosphorus which prevents us from getting the benefits we are conditioned to believe are there. Seems a bit counter-productive, doesn’t it? A study (Heaney RP, Weaver CM. Calcium absorption from kale. American Journal of Clinical Nutrition 1990; 51:656-657) compared the absorption of calcium from kale with the absorption from milk showing that the absorption of calcium from kale was 40.9%, compared to only 32.1% from milk.
So how can we promote our own optimal bone health? The best place to start is ensuring you are taking in adequate amounts of bio-available (absorbable) forms of calcium. Some of my favorite sources include ground sesame seeds, sesame butter (tahini), organic almond butter, organic beans (white, navy, yellow, etc), flax seeds, organic arugula, organic kale, organic collards, seaweed (nori, kombu, etc) and canned salmon (with bones). The list goes on and on.
Supplementation is another option some people may need to consider. But you will need to do your research. Many products on the market offer forms of calcium that the body has a hard time absorbing.
I found the following guideline to be useful when selecting an appropriate supplement:
- calcium asparginate: anhydrous highest amount of absorbable calcium per pill and does not require magnesium supplementation as the other supplements do.
- calcium carbonate (Tums): highest amount of calcium per pill but may cause intestinal gas and/or constipation, and is poorly absorbed
- calcium citrate: less calcium per pill but better absorbed than carbonate. No known side effects
- calcium phosphate: already too much phosphorus in average diet so avoid this form
- calcium lactate: The type of calcium in milk. Usually well absorbed, does not cause latose reaction in most people. Lactate is usually derived from lactic acid
- calcium gluconate: Usually very well tolerated, easily absorbed. Can require many pills to get any amount of calcium
- dolomite: bone meal may be contaminated with lead, know your supplier