The mineral calcium may not seem as “sexy” as other supplements available to consumers today but it certainly has a tremendous amount of research behind it. As most reading these words already know, calcium is a significant component of bones and teeth, giving them strength. As we grow older, bones become weak due to osteoporosis or brittle bone disease. Consuming adequate calcium can go a long way in helping offset the ravages of osteoporosis. The recommended dietary allowance (RDA) for calcium is 1000-1200 mg per day for adults. Some advocate higher amounts (1500 mg per day) for adolescents, given that osteoporosis is now seen as a disease that can start in youth. Men also get osteoporosis so they, too, need calcium. In fact, men have a greater risk of getting osteoporosis than prostate cancer!
The Different Types of Calcium
Calcium comes in different forms. When choosing a calcium supplement, you have to look for “elemental” calcium—the form that we use. Most experts agree that calcium carbonate has the most elemental calcium per dietary supplement. Below is a run down of the percentages of elemental calcium contained in other popular dietary supplements:
As can be seen, calcium carbonate is 40% elemental calcium. Calcium citrate, another popular form, has just 21% elemental calcium. Thus, one would have to use more calcium citrate to get the RDA. Calculating elemental calcium in a calcium supplement is easy when you know the percentages above. For example, if you wanted to calculate how much usable calcium was in a 500 mg calcium citrate supplement, you would multiply the milligrams per supplement by the corresponding percentage.
One of the most hyped dietary supplements in history has to be coral calcium. Very little published peer-reviewed studies exist showing that coral calcium is better than other calcium types. When coral calcium was analyzed for purity, some forms were found to contain low concentrations of lead—a toxic substance.
Calcium for Weight Loss
Studies have been published showing that as people consume more calcium, their weight tends to decrease. One study showed that every 300 mg increase in calcium intake resulted in a 2-6 pound loss in weight! It should be noted that all studies to date have found weight loss following consumption of dairy calcium—not calcium supplements. Currently it's unknown how calcium might be affecting weight loss. It should be remembered that weight gain and obesity is a complex phenomenon and calcium alone is unlikely to be a magic bullet in the battle of the bulge.
Calcium is safe in healthy adults. Those who are using heart and blood pressure drugs called calcium-channel blockers should consult their physician before using calcium supplements because theoretically, calcium supplements might decrease the effectiveness of these drugs.