11.3 – Phosphorus
Learning Objectives
- Discuss the roles of phosphorus in the body
- List food groups that are dietary sources of phosphorus.
Phosphorus is present in our bodies as part of a chemical group called a phosphate group. These phosphate groups are essential as a structural component of cell membranes (as phospholipids), DNA and RNA, energy production (A.T.P.), and regulation of acid-base homeostasis. Phosphorus, however, is mostly associated with calcium as a part of the mineral structure of bones and teeth. Blood phosphorus levels are not controlled as strictly as calcium so the P.T.H. stimulates renal excretion of phosphate so that it does not accumulate to toxic levels.
Dietary Reference Intakes for Phosphorus
In comparison to calcium, most Americans are not at risk of having a phosphate deficiency. Phosphate is present in many foods popular in the American diet including meat, fish, dairy products, processed foods, and beverages. Phosphate is added to many foods because it acts as an emulsifying agent, prevents clumping, improves texture and taste, and extends shelf-life. The average intake of phosphorus in US adults ranges between 1,000 and 1,500 milligrams per day, well above the RDA of 700 milligrams per day. The U.L. set for phosphorous is 4,000 milligrams per day for adults and 3,000 milligrams per day for people over age seventy.
A table showing dietary reference intakes for phosphorus.
| Age Group | R.D.A. (milligrams per day) | U.L. (milligrams of phosphorus per day) |
|---|---|---|
| Infants (0–6 months) | 100* | None |
| Infants (6–12 months) | 275* | None |
| Children (1–3 years) | 460 | 3,000 |
| Children (4–8 years) | 500 | 3,000 |
| Children (9–13 years) | 1,250 | 4,000 |
| Adolescents (14–18 years) | 1,250 | 4,000 |
| Adults (19–70 years) | 700 | 4,000 |
| Adults (> 70 years) | 700 | 3,000 |
Denotes Adequate Intake*
Micronutrient Information Center: Phosphorus. Oregon State University, Linus Pauling Institute. . Updated in June 2014. Accessed June 30, 2019.
Dietary Sources of Phosphorus
| Foods | Serving | Phosphorus (milligrams) | Percent Daily Value 1000 |
|---|---|---|---|
| Salmon | 3 oz. | 315 | 32 |
| Yogurt, nonfat | 8 oz. | 306 | 31 |
| Turkey, light meat | 3 oz. | 217 | 22 |
| Chicken, light meat | 3 oz. | 135 | 14 |
| Beef | 3 oz. | 179 | 18 |
| Lentils* | ½ c. | 178 | 18 |
| Almonds* | 1 oz. | 136 | 14 |
| Mozzarella | 1 oz. | 131 | 13 |
| Peanuts* | 1 oz. | 108 | 11 |
| Whole wheat bread | 1 slice | 68 | 7 |
| Egg | 1 large | 86 | 9 |
| Carbonated cola drink | 12 oz. | 41 | 4 |
| Bread, enriched | 1 slice | 25 | 3 |
Micronutrient Information Center: Phosphorus. Oregon State University, Linus Pauling Institute. Updated on June 2014. Accessed June 30, 2019.
Contributors
University of Hawai’i at Mānoa Food Science and Human Nutrition Program: Allison Calabrese, Cheryl Gibby, Billy Meinke, Marie Kainoa Fialkowski Revilla, and Alan Titchenal
