After calcium, phosphorus is the most abundant mineral in your body, making up around 1% of your body weight.¹It has a number of roles in the body, and in particular, it’s crucial for:²

energy metabolism, or in other words releasing energy from food
maintaining the structure of cells
building strong bones and teeth

Phosphorus is found in a range of foods, for example fish, brown rice and oats, so most people’s diet will provide them with all they need.³ However, you can have too much of a good thing – it can be toxic in very high doses, so it’s important to limit how much you get from supplements.⁴ Phosphorus is available in multivitamins, or as a homeopathic remedy.

What does phosphorus do in the body?

It helps build bones and teeth
Bones and teeth are actually made of a mineral called calcium phosphate. This means our bodies need a dietary intake of phosphorus in order for it to be converted into phosphate to help form new bone cells.⁵
Releasing energy from food
Phosphorus – when converted to phosphate – is also an essential component of ATP (adenosine triphosphate), a store of immediate energy in our cells.⁶
Making cell membranes
The mineral is also used to make a type of fat called ‘phospholipids’, which we need to make our cell membranes. Phospholipids help strengthen our cell membranes, while also giving the cells enough internal space for essential cell structures, like the nucleus.^7,8
How much phosphorus do I need?
Both women and men need 550mg of phosphorus each day.⁹
Do children need phosphorus?

1-3 years – 270mg a day
4-6 years – 350mg a day
7-10 years – 450mg a day
11-18 years – 625mg a day for girls, and 775mg a day for boys¹⁰

Which foods are the best sources of phosphorus?

Phosphorus is found in a range of foods, including fizzy drinks and processed meats. However, healthier choices include animal sources such as:¹¹

salmon
yoghurt
milk and cheese
halibut
turkey and chicken
beef
eggs

Phosphorus is also in the following plant foods, although the body finds it harder to absorb this mineral from plants:¹²

legumes, like lentils and peas
nuts
seeds
wholegrains

Who is at risk of phosphorus deficiency

Phosphorus deficiency is known as hypophosphatemia, but it’s very rare because most people are able to get all the mineral they need in their diet. However, poor diets, eating disorders, alcoholism and problems absorbing phosphorus can deplete your phosphorus levels, leading to a deficiency.¹³

What are the symptoms of a phosphorus deficiency?

bone pain
bone fractures
loss of appetite
muscle weakness
fatigue
anxiety¹⁴

There is also a risk of calcium deposits (calcification) in soft tissue.¹⁵ If you think you may be deficient, ask your GP for a phosphate test to determine phosphorus levels in your blood.¹⁶

What happens if I consume too much phosphorus?

It’s more common to have too much phosphorus in the body than too little. Too much phosphorus can be toxic, so this means you should be careful about how much you get from supplements and also keep an eye on processed foods as many contain phosphate additives. Unlike natural phosphorus in unprocessed foods, phosphate additives are very easily absorbed by the body which means you can end up taking in too much. Foods with large amounts of added phosphate include:¹⁷

processed meats, like ham and sausages
tinned fish
shop-bought cakes and biscuits
fizzy drinks, including cola

At more than 1000mg of phosphorus a day, it can cause:¹⁸

diarrhoea
calcification inside organs and blood vessels
poor absorption of other minerals, including iron and calcium

When taken over a long period, excess doses can also upset the balance of calcium in your bones, increasing your risk of fractures¹⁹ and may be associated with kidney and heart disease.²⁰

When should I take phosphorus supplements?

As phosphorus is so widely available, your diet should provide you with the amount you need each day. However, if you think you may not get enough phosphorus, then you could take a supplement. However, stick to 250mg or less of phosphorus a day from supplements – plus whatever you get from your diet – to avoid toxicity, according to the NHS.²¹