Phosphorus
Phosphorus is the second most abundant mineral in the body, after calcium. About 85% of phosphorus in the body exists in bone.
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
- Being an important cell membrane component
- Being important to hemoglobin’s oxygen delivery function
Recommended Intake
Age Group |
Recommended Dietary Allowance
(mg/day) |
---|---|
0-6 months | No RDA; Adequate Intake (AI) = 100 |
7-12 months | No RDA; AI = 275 |
1-3 years | 460 |
4-8 years | 500 |
9-18 years | 1,250 |
19 years and older | 700 |
Pregnancy and lactation, 18 years and younger | 1,250 |
Pregnancy and lactation, 19 years and older | 700 |
Phosphorus Deficiency
Phosphorus deficiency is called hypophosphatemia. Since phosphorus is present in such a large variety of foods, dietary phosphorus deficiency is rare.
Symptoms of hypophosphatemia may include:
- Loss of appetite
- General weakness
- Muscle weakness
- Bone pain
- Increased susceptibility to infection
- Prickling, tingling, or numbness of the skin in the arm, hands, legs, or feet
- Loss of muscular coordination
Phosphorus Toxicity
Phosphorus toxicity is rare in people with normal kidney function. However, those with kidney problems 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.
The following table shows the upper intake levels for phosphorus. But, it's important to note that these levels are not created for people with kidney disease. If you have problems with your kidneys and are concerned about your phosphorus intake, talk to your doctor.
Age Group |
Tolerable Upper Intake Level (UL) (mg/day) |
---|---|
0-12 months | This amount has not been established. |
1-8 years | 3,000 |
9-70 years | 4,000 |
70 years and older | 3,000 |
Pregnancy and lactation | 3,500 and 4,000 |
Major Food Sources
Are you looking to add more phosphorus to your diet? Here are some good food sources:
Food | Serving Size |
Phosphorus Content
(mg) |
---|---|---|
Skim milk | 8 ounces (227 grams) | 247 |
Plain, nonfat yogurt | 8 ounces (227 grams) | 306 |
Part-skim mozzarella cheese | 1 ounce (28 grams) | 131 |
Egg | 1 large | 86 |
Beef | 3 ounces (85 grams) | 179 |
Chicken | 3 ounces (85 grams) | 135-196 |
Turkey | 3 ounces (85 grams) | 217 |
Fish (halibut) | 3 ounces (85 grams) | 244 |
Fish (salmon) | 3 ounces (85 grams) | 315 |
Almonds | 1 ounce (28 grams) | 136 |
Peanuts | 1 ounce (28 grams) | 108 |
Lentils | 4 ounces (113 grams) | 178 |
RESOURCES:
Choose My Plate—US Department of Agriculture
https://www.choosemyplate.gov
Eat Right—Academy of Nutrition and Dietetics
http://www.eatright.org
CANADIAN RESOURCES:
Dietitians of Canada
http://www.dietitians.ca
Health Canada
http://www.hc-sc.gc.ca
REFERENCES:
Block GA, Port FK. Re-evaluation of risks associated with hyperphosphatemia and hyperparathyroidism in dialysis patients: recommendations for a change in management. Am J Kidney Dis. 2000;35(6):1226-1237.
Hyperphosphatemia—approach to the patient. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T116059/Hyperphosphatemia-approach-to-the-patient. Updated February 2, 2017. Accessed March 10, 2017.
Hypophosphatemia—approach to the patient. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T115235/Hypophosphatemia-approach-to-the-patient. Updated February 2, 2017. Accessed March 10, 2017.
Phosphorus. Oregon State University Linus Pauling Institute website. Available at: http://lpi.oregonstate.edu/mic/minerals/phosphorus. Updated June 2014. Accessed March 3, 2017.
The benefits of phosphorus. Vitamins-Nutrition website. Available at: http://www.vitamins-nutrition.org/vitamins/phosphorus.html. Updated March 10, 2017. Accessed March 10, 2017.
Last reviewed March 2017 by Michael Woods, MD, FAAP