Calcium without phosphorous could lead to bone loss

New research published in the June issue of the Journal of the American College of Nutrition​ shows that osteoporosis patients should receive their calcium in the form of calcium phosphate to reduce the risk of phosphorous deficiency.

The study shows that if calcium intake increases without a corresponding increase in phosphorus, total phosphorus absorption falls and the risk for phosphorous deficiency rises. Phosphorus deficiency may make calcium supplementation less effective and could actually lead to increased bone loss.

The study was carried out to evaluate the effect of calcium intake on the absorption of dietary phosphorus, with special reference to typical calcium intake and the higher intakes used for the treatment of osteoporosis.

The research was prompted by the emergence of therapies for osteoporosis that require high doses of calcium in order to achieve an increase in bone mineral density. Such therapies are often concentrated in older patients who tend to have the lowest dietary intake of phosphorus.

The researchers believed that since the high doses of calcium citrate or calcium carbonate used in calcium co-therapy can bind up to 500mg of phosphorus in the body, calcium co-therapy carries the risk of inducing phosphorus deficiency in patients with low dietary phosphorus intake.

The researchers were concerned that a low intake of phosphorous could jeopardise bone-building treatment in post-menopausal women with osteoporosis.

"This means that even if women at risk for bone loss were taking calcium supplements, without the necessary phosphorus these supplements would not only fail to stem the bone loss, but could even lead to an overall phosphorus deficiency,"​ said Dr Machelle Seibel, a women's health and nutrition expert.

"Phosphorus is required to merge calcium into bone. This typically takes place in the intestinal tract. Without enough phosphorus in their systems, the millions of American women taking over-the-counter calcium supplements may be robbing their bodies' natural store of phosphorus in order to digest the calcium they take. Making sure the calcium supplement contains phosphorus is a good way to avoid this,"​ he added.Despite the fact that phosphorus accounts for approximately half of bone mass mineral, few supplements or food fortificants contain phosphorus.

It is estimated that nearly 50 million American women are phosphorus deficient, and 44 million are currently suffering with osteoporosis.

Currently in the US, Posture-D, distributed by Inverness Medical Innovations, is the only nationally available over-the-counter calcium supplement made with calcium phosphate. The supplement contains the same calcium-phosphorus ratio as healthy bone.

According to Seibel, diet, nutrition and family history are key factors in bone growth and density. "Young women in their teens and twenties should make sure they get the proper amount of calcium and phosphorus through their diet. For women in their 30s and beyond, supplementation may be necessary to provide the proper levels of both calcium and phosphorus. Supplements may also be an option for those who are lactose intolerant or do not eat meat,"​ he said.

"Peri- and post-menopausal women are at a higher risk for bone loss. For this group, the easiest way to ensure that they get the proper nutrients for strong, healthy bones is to supplement their diet with a calcium phosphate supplement,"​ Seibel added.