Phosphorus

Functions

Phosphorus’ functions include:

• Forming bones and teeth
• Growing, maintaining, and repairing of cells and tissues
• Synthesizing and activating proteins, such as enzymes and hormones
• Maintaining acid-base balance
• Producing, regulating, and transferring energy in the body
• Converting carbohydrates, protein, and fat into energy
• Important cell membrane component
• Important in hemoglobin’s oxygen delivery function

Recommended Intake

Phosphorus Deficiency

Phosphorus deficiency is called hypophosphatemia. Phosphorus is present in such a large variety of foods, however, that dietary phosphorus deficiency is rare.

Symptoms of hypophosphatemia may include:

• Loss of appetite
• Anemia
• Muscle weakness
• Bone pain
• ]]>Rickets]]>
• Osteomalacia (softening of the bones)
• General debility
• Increased susceptibility to infection
• Paresthesias (prickling, tingling, or creeping of the skin) in the arm, hands, legs, or feet
• Ataxia (loss of voluntary muscular coordination)

Phosphorus Toxicity

Phosphorus toxicity is rare in people with normal kidney function. However, those with ]]>impaired kidney function]]> may experience hyperphosphatemia, or elevated levels of phosphorus in the blood. Hyperphosphatemia can result in decreased levels of calcium in the blood and overproduction of parathyroid hormone, which can lead to bone loss. Calcium phosphate can deposit in various organs such as blood vessels, joints, lungs, kidneys. Hyperphosphatemia in kidney failure patients is a major cardiovascular risk factor.

Major Food Sources

The major food sources of phosphorus are milk, meats, poultry, fish, cereals, and legumes. About 20%-30% of dietary phosphorus comes from food additives.

Health Implications

Bone Health

Phosphorus plays an important role in the formation of bones. Levels of phosphorus in the body are closely tied to levels of calcium, another mineral instrumental for bone health. The kidneys work to maintain the proper ratio between these two minerals. One study, however, found that high dietary phosphorus can cause increased calcium loss, which, in turn, can cause a decrease in bone density and ]]>osteoporosis]]> .

Tips for Lowering Your Phosphorus Intake

For most people, the kidneys regulate the amount of phosphorus in the body. But people whose kidneys are not functioning properly may need to limit the amount of phosphorus in their diets.

Dietary intake of phosphorus is difficult to limit because the mineral is found in so many foods. The following is a list of specific foods within larger food categories that contain particularly high levels of phosphorus and should be avoided.

• Dairy: Limit your daily intake of milk and milk products to one serving per day.
• Meat:
  • Fin fish such as salmon, pollock, walleye, flounder, sole, tuna, haddock, and swordfish
  • Organ meats
• Legumes:
  • Dried beans
  • Dried peas
  • Dried lentils
• Nuts and seeds
• Breads, grains, and cereals:
  • Bran
  • Brown rice
  • Corn bread
  • Granola
  • Oatmeal
  • Oat bran
  • Pancakes
  • Whole grain breads and cereals
  • Wild rice
• Vegetables:
  • Corn
  • Mushrooms
  • Peas
• Fruits:
  • Avocado
  • Coconut
• Beverages:
  • Beer
  • Soda