What Is Phosphorus?

By Marisa Moore, MBA, RDN, LD
phosphorus

After calcium, phosphorus is the second-most abundant mineral in the body. While it doesn't get as much attention as calcium, phosphorus plays an important role as a building block for bones and teeth, and as a key nutrient in helping the body use and store energy. Phosphorus also helps regulate kidney and nerve function, muscle contractions and heartbeat, and is a critical component for the normal function of every cell in the body.

Calcium and phosphorus combine in a delicate balance to protect the bones from osteoporosis (porous bones), prevent dental problems and to support normal cell function in the body.

Phosphorus is readily found in our food supply and deficiencies are rare in the general population. If your diet includes plenty of variety, you probably get enough phosphorus. Main food sources of phosphorus include meat, poultry, fish, eggs and dairy foods such as milk, yogurt and cheese. Whole grains, beans and nuts are also good sources of phosphorus in the form of phytate, which is not as easily absorbed by the body. On average, we absorb just half of the phosphorus from these foods. 

For people with kidney disease, too much phosphorus can be a concern. Normally the kidneys get rid of any excess phosphorus; however, for those with chronic kidney disease, this process is disrupted and may lead to dangerously high levels of phosphorus in the blood.

Phosphorus supplements generally are not recommended unless under the supervision of a health care provider. Long term use or large doses of antacids that contain aluminum, calcium or magnesium can decrease phosphorus absorption and cause low blood levels of the mineral in the body. Some medications also may interfere in phosphorus absorption or cause low levels of phosphorus in the body. Speak with your health care professional to understand how they may affect your phosphorus levels.

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