Written by Slawomir Gromadzki (MPH)
Phosphorus is an essential mineral which contributes to the bone strength and production of energy from food. It also helps to maintain acid-base balance and activates various enzymes, vitamins and hormones.
In our body, about 85 percent of phosphorus is stored in our bones, but it’s also present in muscles and the blood in smaller quantities.
PHOSPHORUS VS PHOSPHATE & OTHER FORMS
Phosphate as a nutrient should not be confused with a toxic elemental white phosphorus used in laboratories. In the human body and in foods, phosphorus (P) does not appear as a free element but rather as a phosphorus-oxygen compound phosphate (PO4). In the nutritional context, therefore, the terms phosphorus and phosphate are used interchangeably.
In plant foods phosphate appears as phytic acid, in dietary supplements it is found in the form of phosphate salts and it is also commonly used as an food additive in the form of di-calcium phosphate. In soft drinks it appears as phosphoric acid. Phosphate is also part of a mineral hydroxyapatite in the bones and teeth.
RECOMMENDED DAILY INTAKE
The recommended dietary intake for phosphorus for adults is 700 mg per day. Healthy individuals, including vegans, can easily get enough phosphorus from various plant or animal foods. Breast milk contains sufficient amounts of phosphorus for breastfed infants.
Sunflower seeds (1/4 cup, 24g) – 380mg
Pumpkin seeds (1/4 cup, 24g) – 310mg
Soybeans (1/2 cup 90g): 200-300mg
Oatmeal, Potatoes with skin (1/2 cup 90g): 200mg
Beans (1/2 cup 90g): 100-200mg
Nuts (1/2 cup 90g): 50-100mg
Phosphate binders, such as calcium acetate or calcium carbonate, and aluminium or magnesium hydroxide taken with meals, bind phosphorus from foods and reduce its absorption. They are used to deal with high blood phosphate levels in people with chronic kidney disease.
IS TOO MUCH PHOSPHORUS (PHOSPHATE) BAD FOR YOU?
Diet high in both phosphorus has not been proven harmful for bones in healthy individuals.
There is insufficient evidence about the effect of high-phosphorus (phosphate) diet on the kidney stones risk.
PHOSPHORUS (PHOSPHATE) DEFICIENCY (HYPOPHOSPHATEMIA)
Even people on restricted diets are unlikely to develop phosphate deficiency or hypophosphatemia. Phosphorus deficiency refers to low body phosphorus stores, which may or may not result in low blood phosphate levels, because phosphate stores are mainly within the cells.
Chronic hypophosphatemia can result from reduced phosphate absorption due to long-term use of high doses of calcium or magnesium antacids, supplemental calcium and magnesium, vitamin D deficiency, laxatives, chronic diarrhoea, untreated diabetes, kidney diseases, heavy metal poisoning, aluminium, Crohn’s or celiac disease, alcoholism, anorexia nervosa, cancer, or excessive phosphate loss in urine due to overactive parathyroid glands (hyperparathyroidism).
Complications of chronic phosphorus deficiency may include rickets (bone deformities in children) or osteomalacia (soft bones in adults).
Treatment may include removal of the cause, phosphate and vitamin D supplements.
HIGH BLOOD PHOSPHATE LEVELS (HYPERPHOSPHATEMIA)
In healthy people, diet rich in phosphorus does not increase blood phosphate levels but it is possible in individuals with kidney failure.
Other causes may include using phosphate and calcium supplements in high doses, vitamin D intoxication, or cancer.
Symptoms of hyperphosphatemia may include fatigue, itchy skintingling around the mouth, and muscle cramps. Treatment may include low-phosphorus diet, phosphate binders, diuretics and hemodialysis.
Chronic hyperphosphatemia can lead to calcium-phosphate deposits, damage of arteries, skin, tendons, eyes, kidneys, heart valves, and other organs.
Over-the-counter sodium phosphate and potassium phosphate in the form of tablets and capsules are available to help deal with phosphorus deficiency.
Typical doses of supplements to treat hypophosphatemia are 1-3 grams daily.
Phosphates can be effective for lowering high blood calcium levels (hypercalcemia) as oral sodium/potassium phosphate reduce calcium absorption in the gut and stimulates calcium deposition to the bone.
RECOMMENDED DAILY PHOSPHORUS INTAKE
Infants 0–6 months: 100 milligrams daily
Infants 7–12 months: 275 milligrams
Children ages 1–3: 420 milligrams
Children 4–8: 500 milligrams
Ages 9–18: 1,250 milligrams
Adults ages 19–50: 700 milligrams
Pregnant or breastfeeding women: 700 milligrams
The Safe Upper Intake Level for phosphorus is 3,000-4,000 mg per day. However, it does not apply to people with kidney failure in which phosphate intake should be determined individually.
Harmful effects for the babies and during pregnancy are not known due to the lack of human studies. Supplemental sodium phosphate during pregnancy should be taken only when needed due to deficiency.
According to some reliable sources, phosphate salts in recommended daily doses are likely safe during pregnancy and breastfeeding.
Phosphates reduces the absorption of iron, calcium and magnesium.
Calcium, magnesium and aluminium antacids, iron supplements, anticonvulsant phenytoin and bile acid binders cholestyramine and colestipol reduce phosphate absorption.
MILK & ACETIC ACID
Excessive concentration of calcium and phosphate in the urine after consuming milk products, can result in cloudy urine and formation of phosphate crystals in urine (increasing the risk of calcium kidney stones). However, few drops of acetic acid (from apple cedar vinegar) clear urine that is cloudy due to phosphates.
STRONG BONES & TEETH
Phosphorus is important in the body for maintaining bone structure and strength. It helps form bone mineral density that prevents bone fractures, breaks and osteoporosis – which all are more likely as someone ages. In fact, more than half of all bone is made from phosphate. Without enough phosphorus present in the bone, calcium cannot properly build and maintain healthy bone structure. In addition, high levels of calcium from diet (milk, dairy products, etc.) and supplements (calcium carbonate) can block absorption of phosphorus and weaken bones and teeth. Similar negative effect takes place in case of the deficiency of vitamin K2, D, boron and magnesium.
DETOXIFICATION & KIDNEY FUNCTION
Phosphorus supports kidney function and helps us to eliminate toxins through urine. In order to maintain normal levels of uric acid, sodium, water and fat, kidneys need electrolytes like phosphorus, potassium and magnesium.
METABOLISM & ABSORPTION OF NUTRIENTS
Phosphorus helps produce digestive enzymes that convert carbohydrates and fats into useable energy.
It is needed to properly synthesize, absorb and use vitamins and minerals from food. It is also important for synthesizing amino acids in order to help with cellular function, energy production, reproduction and growth.
Phosphorus also helps balance levels of vitamin D, magnesium, calcium, zinc, and iodine to support a healthy metabolism.
PH BALANCE, GUT HEALTH & DIGESTION
Inside the body, phosphorus partially occurs as phospholipids, which are a major component of most biological membranes. The roles of these phospholipids include balancing the body’s pH level by buffering excess levels of either acid or alkali compounds. This helps with digestion by allowing healthy bacteria within the gut flora to flourish.
Since it acts as an electrolyte, phosphorus helps improve digestion by reducing water retention and diarrhoea, and it provides natural constipation relief and helps ease acid reflux.
Phosphorus helps with the absorption and regulation of B vitamins that are vital to energy production within cells, in the form of ATP. B vitamins are also needed to maintain a positive mood due to their effect on neurotransmitter release in the brain.
Additionally, it aids in the transmission of nerve impulses that help control muscle movement. A deficiency in phosphorus and lack of foods high in phosphorus can lead to general weakness, muscle aches and soreness, numbness, and general or chronic fatigue syndrome.
Proper neurotransmitter and brain functions rely on minerals like phosphorus in order to carry out everyday cellular activities. A key role of phosphorus is helping maintain proper neurological, emotional and hormonal responses.
A phosphorus deficiency has been linked with cognitive decline and the development of age-related neurodegenerative disorders, including Alzheimer’s disease and dementia.
GROWTH AND DEVELOPMENT
Because phosphorus is vital for nutrient absorption and building bones, a deficiency during toddler and adolescent years can stunt growth and contribute to other developmental problems. During pregnancy, it plays a role in the production of the genetic building blocks, DNA and RNA.
Indeed, foods high in phosphorus are key in a pregnancy diet because the mineral is needed for the growth, maintenance and repair of all tissues and cells starting from infancy. Phosphorus is also important for proper brain function, including the ability to concentrate, learn, problem-solve and remember information.