Phosphorus, following calcium, is the second most abundant mineral in the human body. Approximately 80 percent of phosphorus is present in the skeleton while the other 20 percent is very active metabolically and plays a role in the metabolism of every cell in the body. Phosphorus participates in more biological processes than any other mineral.

Phosphorus is so abundant in our food supply that it is rarely used therapeutically. However, some other nutritional products contain phosphorus. Some examples of phosphorus-containing products are the calcium supplement dicalcium phosphate and phosphatidyl choline and phosphatidylserine, which are known as phospholipids.

Dosage Info

Dosage Range

800-1,200mg daily.

Most Common Dosage


Dosage Forms

Tablets and capsules.

Adult RDI


Adult ODA



  • Infants <6 months: 100mg (Adequate Intake, AI)
  • Infants 7-12 months: 275mg (AI)
  • Children 1-3 years: 460mg
  • Children 4-8 years: 500mg
  • Children 9-18 years: 1,250mg
  • Adults >19 years: 700mg
  • Pregnancy 19 years: 700mg
  • Lactation 19 years: 700mg

Interactions and Depletions



Active Forms

Dicalcium phosphate, phosphatidyl choline, phosphatidylserine.


Phosphate is absorbed from the jejunum in the small intestine. 1,25-dihydroxycholecalciferol, otherwise known as 1,25-dihydroxy vitamin D3 regulates the absorption of phosphate. If serum phosphate levels are low, more 1,25-dihhdroxy vitamin D3is formed in the kidneys,which stimulates phosphate absorption from the intestines.

Toxicities & Precautions


Excessive consumption of high phosphorus-containing foods, such as animal protein and cola soft drinks, may inhibit calcium absorption and contribute to skeletal problems such as osteoporosis. (1)

Excess phosphorus can increase the incidence of hyperthyroidism, (2) bone resorption, (3) and the deposition of calcium into soft tissue. (4) , (5) , (6)

Functions in the Body

Bones and Teeth

Phosphorus, along with calcium, forms insoluble calcium phosphate crystals, which provide the strength and rigidity in bones and teeth.

Soft Tissues

Unlike calcium, phosphorus is also an integral part of the structure of soft tissues. As part of phospholipids, such as phosphatidylcholine, it is a component of all cellular membranes. Phospholipids aid in transporting other lipids throughout the body and across cellular membranes.


ATP contains three phosphate groups and thus, phosphorus is an essential part of energy storage and production processes in every cell throughout the body.

Enzymatic Reactions

Part of many co-enzymes and takes part in a wide variety of enzymatic reactions.

Buffering Systems

As phosphoric acid and its salts, phosphorus is part of one of the body’s major buffer systems.

Part of DNA and RNA

Thus, necessary for all cellular reproduction and protein synthesis.

Symptoms and Causes of Deficiency

Phosphorus deficiency has been reported in animals, but it rarely occurs in humans. Long-term use of aluminum-containing antacids could lead to phosphate depletion. Individuals who might be at risk to phosphorus depletion include alcoholics, people with kidney malfunction, individuals with intestinal malabsorption syndromes such as celiac disease or Crohn’s disease, and individuals on starvation diets.

Dietary Sources

Animal protein foods are the best source of phosphorus for most people. Cola soft drinks also contain a large amount of phosphorus.


  1. View Abstract: Mazariegos-Ramos E, et al. Consumption of Soft Drinks with Phosphoric Acid as a Risk Factor for the Development of Hypocalcemia in Children: A Case-control Study. J Pediatr. Jun1995;126(6):940-42.
  2. View Abstract: Popelier M, et al. Phosphorus-calcium Metabolism in Hyperthyroidism. Presse Med. Apr1990;19(15):705-08.
  3. View Abstract: Draper HH, et al. Calcium, Phosphorus, and Osteoporosis. Fed Proc. Jul1981;40(9):2434-38.
  4. View Abstract: Alfrey AC, et al. Bone Pyrophosphate in Uremia and its Association with Extraosseous Calcification. J Clin Invest. Mar1976;57(3):700-05.
  5. View Abstract: Calvo MS. Dietary phosphorus, calcium metabolism and bone. J Nutr. Sep1993;123(9):1627-33.
  6. View Abstract: Calvo MS, et al. Changing phosphorus content of the U.S. diet: potential for adverse effects on bone. J Nutr. Apr1996;126(4 Suppl):1168S-80S.