Recommended Nutrient Intakes for Vitamin and Minerals

Phosphorus

Functions

Phosphorous is the second most abundant mineral in the body. About 85% of phosphorous is found combined with calcium in the hydroxyapatite crystals of bones and teeth. Phosphates (phosphorous salts) are found in all cells in the body. They are part of a major buffer system. Phosphorous is also part of DNA and RNA, and is therefore necessary for all growth.

Phosphorous also assists in energy transfer during cell metabolism. Phosphorous activates many enzymes and B vitamins. ATP which is the energy carrier for all cells, contains 3 phosphate groups.

Some lipids contain phosphorous as part of their structures. These are known as phospholipids. These phospholipids form part of the lipoproteins which help transport other lipids around the body and are major structural components of cell membranes, where they affect transport of nutrients into and out of cells.

Some proteins e.g. casein in milk, also contain phosphorous and are known as phosphoproteins.

Recommended Intakes

Table: Recommended Intakes for Phosphorous (mg/day)

Food Sources

Significant sources of phosphorous include all animal tissues, e.g. meat, fish, poultry, eggs, milk. Processed foods e.g soft drinks contain high amounts of phosphorous. Phosphorous from additives in foods can add substantially to intake.

Deficiency

In general diets which provide adequate energy and protein also supply adequate phosphorous. Dietary deficiencies of phosphorous are unknown.

Deficiency symptoms of phosphorous include muscle weakness and bone pain.

Toxicity