How much phosphorus do adults need?

Adults need 700 milligrams a day (US, NIH). In the UK: 550 milligrams a day (NHS).

What is the upper limit for phosphorus?

US: 4,000 milligrams a day, or 3,000 over age 70. UK (NHS): up to 250 milligrams a day from supplements on top of your diet is unlikely to cause harm.

Which foods have phosphorus?

Milk and cheese, meat and poultry, fish, eggs, nuts, beans and lentils.

Phosphorus: what it does and how much you need

Phosphorus helps build bones and teeth and helps the body make energy. Adults need 700 milligrams a day, and the upper limit is 4,000 milligrams a day, or 3,000 over age 70.

Checked 28 September 2026 with Supplement Check's data from the NIH fact sheet and NHS guidance · Adults only

General information, not medical advice. Check with a doctor or pharmacist before taking a supplement, especially if you are pregnant or breastfeeding, take any medicine, or are under 18.

In the UK

In the UK, adults need 550 milligrams a day, and the NHS says up to 250 milligrams a day from supplements on top of your diet is unlikely to cause harm.

How much you need and the upper limit

	US (NIH)	UK (NHS)
Adults need	700 milligrams a day	550 milligrams a day
Upper limit	4,000 milligrams a day, or 3,000 over age 70	Up to 250 milligrams a day from supplements on top of your diet

The UK figure is the amount the NHS says is unlikely to cause harm. Figures are for adults.

Food sources

Milk and cheese
Meat and poultry
Fish
Eggs
Nuts
Beans and lentils

Quick answers

What does phosphorus do?: Phosphorus helps build bones and teeth and helps the body make energy.
How much phosphorus do adults need?: Adults need 700 milligrams a day (US, NIH). In the UK: 550 milligrams a day (NHS).
What is the upper limit for phosphorus?: US: 4,000 milligrams a day, or 3,000 over age 70. UK (NHS): up to 250 milligrams a day from supplements on top of your diet is unlikely to cause harm.
Which foods have phosphorus?: Milk and cheese, meat and poultry, fish, eggs, nuts, beans and lentils.

Sources

NIH Office of Dietary Supplements fact sheet
https://ods.od.nih.gov/factsheets/Phosphorus-HealthProfessional/
NHS vitamins and minerals guidance
https://www.nhs.uk/conditions/vitamins-and-minerals/others/

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