Bone health II: the calcium debate

Posted by kathryn in The Micronutrients

I posted yesterday on what bones are and why we have them . As I mentioned, there’s a lot of debate about calcium and the best ways to ensure strong and healthy bones.

Calcium from milk

When people think of calcium, they tend to think milk and it’s true that most dairy foods contain a lot of calcium. The perception is if you drink and eat lots of dairy, you’ll have strong bones and prevent osteoporosis. However, it’s not that simple.

Calcium is important, but it’s not the only factor required for healthy bones. Large scale studies, such as the Nurses Health Study, have shown that dairy consumption alone will not guarantee you prevent osteoporosis. In addition, India, Japan and Peru all have a low intake of dairy and calcium in general, and yet the incidence of bone fractures in these countries is also low.

Other factors

While we know a lot about the human body and how it functions, there are still large areas of uncertainty. This is definitely true in the nutrition arena and calcium is one of those topics.

While it’s known that calcium is a primary constituent of bones and that diet and lifestyle factors influence bone health, we don’t have all the answers as to how and why.

For starters, there’s conflicting evidence about how much calcium we need. Here in Australia, for most of the population, the recommendation is for 1,000mg per day. However, in India, Japan and Peru total calcium intake is less than a third of this figure.

Some people have also expressed concerns about the bioavailablity of calcium from milk that has been heavily processed, as it is these days.

The importance of physical activity

One of the most important factors for healthy bones has nothing to do with diet . It’s physical activity.

The importance of load-bearing activity in building up stong and healthy bones can not be under-stated. When subjected to some strain and stress, your bones respond by building up strength and density.

Regular physical activity also increases muscle strength and coordination, which reduces the risk of falls and stumbles and therefore fractures.

What does all this mean?

In the last post in this series, I’ll be tieing all this information together and answering the question: how best to ensure strong and healthy bones?

Part one of this three-part series is Bone health I: what are bones.

11 July, 2007