Vitamin D is essential for promoting calcium absorption in the gut.

CNN: How much vitamin D should someone over 55 take?

Finally, don't smoke, and limit alcohol and coffee consumption (too much caffeine can impair the absorption of calcium) for a complete osteoporosis prevention program.

CNN: How much weight is needed to strengthen my bones?

If you take iron supplements, make sure to take them separately from calcium supplements, which can interfere with their absorption.

CNN: Will eating meat help recovery after long runs?