Confused about calcium? If so, you are not alone!

When we think about calcium, most of us think first of bone density, and there has been lots of research on this topic. Given that we have learned so much, you might wonder why there is still so much contradiction about what’s best!

Science is always updating our knowledge, but sometimes what is learned can take half a century to get to the public. Meanwhile, the profusion of differing research results can create confusion. Over time, as information is integrated, we start to see the bigger picture.

It is clear that reduced bone density causes increased fractures in menopausal women. In the Western world, the incidence of disability and mortality associated with osteoporosis is almost as high as the disability and mortality of most cancers. It’s a significant factor in the health of an aging population.

It is important to understand the difference between increased bone density and reduced fracture risk, because they are not necessarily inversely proportional. We might expect denser bones would be less likely to break, but as far as fracture risk is concerned, the quality of bone is at least as important as its density, and reducing fracture risk is the most important outcome.

Here’s some history of that research:

Given we know that calcium is the main mineral in bones, trials looked at whether we could increase bone density by supplementing calcium. Some improvement in bone density was seen with doses of 1,000mg to 1,200 mg a day, so that much was then recommended as a daily intake. Because calcium was the sole focus of this research, folks just took it as a single substance supplement.

But calcium is a mineral, and minerals are alkalizing. The most readily available inexpensive form is calcium carbonate: the calcium in the antacid TUMS. People taking TUMS for their calcium were also affected by those antacid properties, reducing stomach acid. This not only reduces digestion and absorption of calcium, but also reduces the absorption of the rest of the nutrients from their food as well!

Further research found that people on this much calcium were tending to have more cardio-vascular problems, especially heart attacks. This was bad news in and of itself, of course, and pointed to the calcium being deposited in the wrong tissues: the arteries. Clearly time for a re-think!

Recognizing that vitamin D is so important in absorbing calcium in the gut and in making healthy bones, trials then gave people calcium with vitamin D. Their bone density improved more than with calcium alone, but the cardio-vascular consequences still followed.

Two articles in the British Medical Journal in 2011 concluded that “calcium supplements, with or without vitamin D, modestly increased the risk of cardiovascular events, especially heart attacks”, and that the risk was the same when people took vitamin D with their calcium as when they took calcium alone. Indeed their meta-analysis indicated that for every 1000 people using calcium or calcium plus vitamin D, three fractures would be prevented, but at a cost of six heart attacks or strokes being triggered. Clearly not an overall benefit!

This is likely the reason that some doctors are now telling people not to supplement calcium, but to focus on getting it from their diets. We say that people doing that should at least ensure that their vitamin D levels are excellent, rather than deficient or just OK, or they won’t be able to get the full benefit of the calcium in their food.

Magnesium to the rescue!

In 2021 a review of studies on magnesium and bone health concluded that people with low dietary magnesium had lower bone density and a higher fracture rate, and supplementing with magnesium improved bone density and reduced the tendency to fracture.

It turns out that magnesium is necessary to turn on all of the enzymes that activate vitamin D, enabling vitamin D to escort calcium into bones: a natural biochemical synergy. This is likely the mechanism by which magnesium mitigates the cardio-vascular risks of taking calcium and vitamin D, so we consider magnesium crucial in any bone support supplement.

Other synergistic supplements also show promise:

• Vitamin K - has a double benefit: it helps take calcium from the arteries and puts it in the bones

• Boron - shown to decrease calcium loss in urine

• Silica - Thirty years of evidence suggest an important role in bone formation and bone health, although the mechanisms are unclear

• Strontium has some bone-building effects, so may have a useful part to play

• Resveratrol has been shown to be helpful for better bone density in menopausal women

• Eating fruits is helpful yet again: people who had a history of eating fruits had better bone density, likely due to dietary vitamin C

We hope to see more studies on how these substances may help promote bone strength and density, especially if used in synergy, the way nature does it!

There is so much research providing pieces of a bigger puzzle, but not giving really clear overall answers, hence all the confusion. But we are no longer confused about whether to supplement just calcium and vitamin D: the answer is not to take them unless you also take magnesium. And you are probably better taking other minerals and trace minerals too.

We couldn’t write about bone density without mentioning exercise. Just as muscles increase in size and strength as you exercise them, so do your bones. You just can’t see it!