Lenore Greenstein: Phosphorus can help prevent osteoporosis

Although our bones are mostly made of calcium, phosphorus is the mineral that gives them rigidity and structure. Yet studies show that phosphorus is an essential mineral that may be lacking in the diet of many people.

Foods containing the largest amount of phosphorus are meat, eggs and milk, and vegetables such as asparagus, kale and broccoli which contain smaller amounts. Because of the growing concern about cholesterol in these foods, many people are eating less eggs and meat. Since a large group of individuals are lactose intolerant, there is a decrease in the consumption of milk and milk products, and the growing number of vegetarians and individuals on weight-loss programs has further reduced the amount of phosphorus-containing foods in their diets.

According to the national Health and Nutrition Examination Survey, about 50 million women and 7 million men over the age of 30 consume less than the Daily Recommended Allowance of 1,000 milligrams of phosphorus in their diets every day.

In order to form and maintain bones, many people are taking calcium supplements, yet most of the calcium supplements on the market today do not contain any phosphorus at all, which is needed to complement the calcium in bone formation.

Researchers at Creighton University in Omaha, Neb., studied the metabolism of a group of women who were found to have low levels of phosphorus, to discover the relationship between calcium and phosphorus and their bone health. The subjects who took a calcium supplement with phosphorus actually gained bone.

Those women with low blood levels of phosphorus who took a calcium supplement without added phosphorus actually lost bone. It appeared that the calcium in the supplement bound to any phosphorus which was present in their intestinal tract, lowering their blood levels of phosphorus even more.

The results of a national consumer survey of 1,330 women early this year showed that more than 90 percent of women knew that calcium was good for their bones, but 83 percent were unaware of the beneficial effects of phosphorus on bone health.

Phosphorus can be found in dairy products such as milk and yogurt, beef, poultry, seafood, almonds and lentils.

In a recent study to assess the impact of phosphorus on bone mineral density, researcher Katherine L. Tucker and her team found that colas, but not other carbonated soft drinks, contributes to a loss of bone in adult women. The researchers concluded this decrease in bone density was attributed to the phosphoric acid content of cola, since excess phosphoric acid binds to calcium and keeps it from being absorbed. The substitution of phosphate containing soft drinks and snack foods for milk and other calcium rich foods also represent a serious risk to bone health in general.

The bottom line is to consume a balanced diet, including adequate phosphorus as well as calcium contained in many protein foods and dairy products. When it comes to supplementing the diet with added calcium, look for a product that also contains phosphorus, so they can do their job together and build stronger bones.

Lenore S. Greenstein is a licensed and registered dietitian in the Naples area.