Phosphorus is a mineral found in bones, teeth, DNA and ATP, the molecule cells use to store energy, and many protein-rich foods provide it1.
With calcium it forms hydroxyapatite, the main building block of bone and tooth enamel; about 85% of body phosphorus is there1.
Part of ATP, the body's key energy source, and involved in storing energy inside cells1.
A component of DNA and RNA and, as phospholipids, of cell membranes1.
Helps maintain normal pH in the fluid outside cells and helps activate enzymes1.
Works with B vitamins in kidney function, muscle contractions, a normal heartbeat and nerve signalling2.
Phosphorus is absorbed in the small intestine, mostly passively and partly by active transport, and the kidneys, bones and intestines keep blood levels in balance1. Calcitriol (active vitamin D) increases uptake from the diet, while parathyroid hormone and FGF23, made mainly by bone cells, make the kidneys excrete more phosphate3.
| Food and serving | Amount |
|---|---|
| Yogurt, plain, low fat, 6 oz | 245 mg |
| Milk, 2%, 1 cup | 226 mg |
| Mozzarella, part skim, 1.5 oz | 197 mg |
| Lentils, boiled, ½ cup | 178 mg |
| Cashews, dry roasted, 1 oz | 139 mg |
| Potato, russet, baked with skin, 1 medium | 123 mg |
| Kidney beans, canned, ½ cup | 115 mg |
| Brown rice, cooked, ½ cup | 102 mg |
| Food and serving | Amount |
|---|---|
| Salmon, Atlantic, farmed, cooked, 3 oz | 214 mg |
| Scallops, breaded and fried, 3 oz | 201 mg |
| Chicken breast, roasted, 3 oz | 182 mg |
| Beef patty, 90% lean, broiled, 3 oz | 172 mg |
| Egg, hard boiled, 1 large | 86 mg |
Phosphorus in seeds, beans and unleavened bread is mostly phytic acid, which the body absorbs poorly; overall 40–70% of food phosphorus is absorbed, more from animal foods than plants1. Amounts per serving from1.
Additives such as phosphoric acid and sodium phosphate in processed foods can add a sizeable share of daily phosphorus, and about 70% of it is absorbed1.
Sold alone, in combinations and in a few multivitamins; most products provide only a small amount1.
U.S. labels have to list phosphorus only when it has been added to the food1.
The same reference table draws the reference lines on your charts in Ayuvo. Needs differ in pregnancy and breastfeeding, which are not covered here.
| Age | Women | Men | Upper limit |
|---|---|---|---|
| 19–30 | 700 mg | 700 mg | 4,000 mg |
| 31–50 | 700 mg | 700 mg | 4,000 mg |
| 51–70 | 700 mg | 700 mg | 4,000 mg |
| 71+ | 700 mg | 700 mg | 3,000 mg |
RDA (Recommended Dietary Allowance) is the daily amount that meets the needs of nearly all healthy people. Per day, for adults1.
Upper limit (UL) is the most per day that is unlikely to cause harm. Applies to food, drinks and supplements combined.
Signs like these have many possible causes. They are a reason to talk to a clinician, not to self-treat.
Deficiency (hypophosphatemia) is rare and almost never caused by a low intake; it usually comes from medical conditions, and long-term use of aluminium antacids can contribute1.
High intakes rarely cause problems in healthy people, but very large short-term doses, such as sodium phosphate laxatives above the label dose, can push blood phosphate too high1.
Phosphorus status is not usually assessed, but phosphate can be measured in serum or plasma; blood levels do not necessarily reflect how much phosphorus the whole body holds1.
| Serum phosphate | What it may mean |
|---|---|
| 2.5–4.5 mg/dL (0.81–1.45 mmol/L) | Normal range for adults |
| Below that range | Hypophosphatemia |
| Above that range | Hyperphosphatemia |
Labs use different units and ranges. Your clinician reads a result alongside your history and other tests.
Phosphorus comes in phosphorus-only products, combination supplements and a few multivitamins, usually as phosphate salts or phospholipids1.
Such as dipotassium or disodium phosphate; about 70% is absorbed1.
Such as phosphatidylcholine or phosphatidylserine; how well their phosphorus is absorbed has not been measured in people1.
Not a supplement, but a large phosphorus source; doses above the label have been linked with serious harm, especially with kidney or heart disease1.
Supplements can interact with medicines. Talk to a clinician or pharmacist before you start one, especially at high doses.
Yes. Surveys show most U.S. adults eat more than the recommended amount, and deficiency is almost never caused by diet. When it happens, it is usually linked with medical conditions, some medicines or severe malnutrition.
Healthy kidneys remove extra phosphate in urine. When kidney function declines, phosphate can build up in the blood, which is linked with bone problems and calcium deposits in blood vessels. People with kidney disease usually get specific advice on phosphorus from their care team.
Cola contains phosphoric acid, but a cup provides only about 18 mg of phosphorus, far less than a cup of milk. Phosphate additives spread across many processed foods add more to total intake than any single drink.
Food logging does not estimate phosphorus, so Ayuvo tracks it from supplements you log in Medications, and from Apple Health on iPhone or Health Connect on Android when another app saves it there. Charts by day, week, month and year use the reference lines from this page, personalised by age and sex where they differ. Free, with no account.
Or read the code: Ayuvo is open source
Facts on this page come from these sources, checked on the dates shown. Intake numbers come from Ayuvo's shared reference table, which cites the sources marked for them.
General information, not medical advice. This guide is for healthy adults and does not cover pregnancy, breastfeeding, children or medical conditions. It cannot diagnose or treat anything. Talk to a clinician before starting high-dose supplements, or if you think you may have too little or too much of a nutrient. Spotted an error? Email us.