Osteoporosis? Let’s Keep Moving!

November 10, 2015 in Exercise, Health, Nutrition by Joyce Bunderson

I love science – that’s no surprise to those who know me. But having said that I also recognize that I’m not the most patient person and nutritional science is relatively a young field. I wish we could learn; and learn fast, but alas, good methodical science frequently doesn’t happen quickly.

What’s brought me to this thought process is our mineral friend calcium. Calcium is essential to a vast array of processes that constantly keep our bodies functioning – 24/7. The exact amount of calcium in our blood serum is tightly regulated by excretion of excess and/or absorption. To be sure that the blood serum can maintain that strict requirement, calcium is stored in the bones; where it can be called upon at any time. It’s actually pretty remarkable how the body works.

So this is where the tale of science-based advice about calcium begins a fluctuating, confusing saga. One thing about science is that, it does not always provide evidence for current views. For example, it seems pretty straight forward that if you’re seeing an increasing number of people (mostly women) with osteoporosis and broken bones, then you better find ways to help them get more calcium into their bones.

In the 1980s while I was at UCLA studying for a Masters in Public Health Nutrition, research on this very problem was being conducted. At that time, one of my professors informed me (being a woman with very small bones), that I should immediately begin taking oral supplements of calcium. I did not even share the information that my female ancestors had osteoporosis. But very shortly thereafter, I began taking TUMS (calcium carbonate). What an easy fix! Yeah, I won’t get osteoporosis! About 6 months later, Ouch!, Ouch!, Ouch!, severe pain. I ended up in the emergency room taken by ambulance. I had no idea at that time that kidney stones could cause pain worse than the natural childbirth I had endured three times. After some eight hours of suffering and lots of tests, I was told that it was just kidney stones passing. Follow-up with an urologist advised me to no longer take calcium supplements. I followed that advice; never wanting to have kidney stones again.

A couple of months after this happened to me, my sister ended up in intensive care for a week with pyelonephritis (infection in kidneys) that also involved her liver. You guessed it; it was caused by kidney stones, from taking calcium supplements. The point here is that I’ve known this potentially deadly risk with calcium supplements for decades.

In spite of being a serious opponent of taking supplements, on the passionate advice of my rheumatologist, I began taking calcium supplements again in 2013. I was told that rheumatoid arthritis would devour my bones and I really needed to take the calcium supplements again. What a roller coaster! Yes, I followed that advice for about 2 years.

Then on September 29, 2015 the British Medical Journal (BMJ) published a systematic review of studies that looked at calcium intake from both supplements and from food, and later fractured bones. They wanted to examine the evidence for recommendations to increase calcium through the use of calcium supplements or dietary sources. This review of both randomized control trials and observational studies of calcium intake with fracture as an endpoint were pooled into meta-analyses. The bottom line was that neither supplements nor food sources reduced fractures. They even say that extra calcium can build up in the arteries, causing heart disease, or the kidneys, causing kidney stones. As noted above, I don’t need to be convinced about the stones. On the issue of heart disease – YIKES!!! I try to follow my physician’s recommendations, but I thought, “If my family history of heart disease takes me out early enough to not get osteoporosis, then I can rest on the osteoporosis problem.” OK, not really, but this is an issue to consider.

I was really surprised by the finding of the BMJ that showed that even eating calcium-rich foods such as dairy products did not reduce bone fractures of those over 50. Not only did they find that taking supplements was not helpful, but the more you took, the more harmful side effects. Also, the more you took, the fewer fractures (slightly). That was the last straw for me. So again I went off the calcium supplements.

Back in 2012, the U.S. Preventive Services Task Force began saying that there’s not enough evidence to recommend taking calcium or vitamin D supplements, and even recommending against it in some cases. This study built on that earlier work and strengthened the same recommendation.

Meta-Analyses have been strongly criticized as possibly ending up with misleading results. They are best when based on one type of research, especially large, randomized clinical trials. This study combined a few clinical trials with many more cohort studies and thus was not ideal, but it covered more ground. Despite problems with meta-analyses, and according to my local measurement and research expert, they used good methods that evaluated the possibility for bias in the studies, and did not pool individual data where it was questionable to do so. Moreover, they are building on previous studies, both meta-analyses and clinical trials, and have only pushed the validity argument, (as he calls it), further on their interpretation of this data. They confirmed previous recommendations. But they also showed that higher doses of supplements are linked to dangerous side effects, like kidney stones and perhaps cardio-vascular risk. So they are justified in saying that higher calcium supplement doses do not produce enough benefit to offset the risks.

I’m not going to advise you in the decisions that you make. I used my own experience to illustrate how complex these issues are. From my perspective, I think that the best advice I can share is to keep doing your weight-bearing exercises. Other than swimming and bicycling (Which are not considered weight-bearing exercises.) you can do just about any activity where gravity is pulling on you. Certainly swimming and biking are terrific aerobic exercise; just not weight-bearing exercise. Just plain old walking is a good place to begin. But weight lifting/weight training, jogging, hiking, climbing stairs, tennis, racquetball and dancing are other good options. Even yoga and Tai Chi have been shown to increase bone mineral density. So remember to get out of the chair frequently; even a little break from sitting for long periods is better than nothing. Work up to a nice weekly routine with some variety. The pressure of the exercising muscle on the bone seems to drive calcium into the bone. So let’s keep moving!