Phosphate deficiency and excess

Almost all foods contain natural phosphorus; many contain artificially produced phosphate. For a healthy person, it is almost impossible to suffer a phosphorus deficiency. The danger of taking in too much of the mineral is much greater and can be a danger especially for people with impaired kidney function. How does a phosphate deficiency or excess develop, what are the symptoms?

Phosphate deficiency, in technical terms hypophosphataemia, is very rarely due to insufficient dietary phosphate intake. It is more likely to occur in connection with diseases or the intake of certain medications:

Chronic intestinal diseases such as ulcerative colitis or Crohn's disease can lead to a mineral deficiency. On the one hand, you may have less appetite due to pain, diarrhoea and nausea, and therefore take in fewer minerals. You may also avoid certain foods because you are afraid of the pain. If your intestines are inflamed, it is harder for them to absorb and use the nutrients they offer. If you have diarrhoea, you will lose vitamins and minerals along with the fluid. In the long term, this can lead to mineral deficiencies, such as phosphate deficiency.

Kidney dysfunction, for example caused by increased alcohol consumption or other causes, can lead to a phosphorus deficiency. Already from an alcohol content in the blood of 0.5 per mille, your kidneys dehydrate the body and flush out minerals.  

Hyperfunction of the parathyroid glands can be the reason for a phosphorus deficiency. If they produce too much parathyroid hormone, calcium and phosphorus are mobilised from the bones. At the same time, parathyroid hormone causes a reduced excretion of calcium and an increased excretion of phosphorus with the urine, which lowers the phosphorus level in the blood. In the long term, this can lead to a phosphorus deficiency.

Long-term use of aluminium-containing medicines against heartburn, so-called antacids, can lead to a phosphorus deficiency. Aluminium hydroxide and the phosphate present in the body form insoluble compounds that settle in the intestine and cannot be dissolved again. Thus, aluminium hydroxide withdraws the phosphate needed by the body.

A vitamin D deficiency can lead to phosphate deficiency because vitamin D is responsible for regulating the phosphate level in the blood, along with the parathyroid hormone.

Hereditary hypophosphataemia is also called phosphate diabetes. In this case, the reabsorption of phosphate is disturbed, so that too much phosphate is excreted in the urine. The phosphate deficiency reduces the storage of calcium in the bones, resulting in severe bone growth disorders. This disease already manifests itself in infancy.

A phosphate deficiency leads to a disturbance of all cell functions and cell metabolic processes. Visible symptoms are mainly seen in the bones: Growth disorders, skeletal deformities and osteomalacia (softening of the bones) are the consequences. But muscle cramps, susceptibility to infections, weight loss, fatigue and exhaustion are also among the symptoms. Prolonged phosphorus deficiency leads to muscle weakness, which also affects the heart and diaphragm. Cardiac arrhythmias, heart failure and breathing difficulties can result.

Phosphate deficiency often goes undetected

A deficiency can go unnoticed for a long time because the body can help itself to the phosphate from the bones for years. A mild deficiency without symptoms can usually be remedied by a balanced diet, a severe deficiency usually requires intensive medical care.

With a balanced diet, it is almost impossible to have a health-threatening elevated phosphate level, in the technical term hyperphosphataemia. Patients with elevated phosphate levels often have a pre-existing condition:

Impaired kidney function is a common cause of excess phosphate. The body excretes less phosphorus in the urine, so phosphorus accumulates in the body.

Sodium hydrogen phosphate is a medicinally active ingredient in laxatives. Excessive use of laxatives, for example to support a diet, can be the cause of excess phosphorus.

If the parathyroid gland is underactive, too little parathormone is produced. Parathyroid hormone, together with vitamin D, regulates phosphorus metabolism. If there is a high level of phosphorus in the blood, parathormone ensures that more phosphorus is excreted in the urine, so that the phosphorus level in the blood is lowered. If too little parathyroid hormone is produced in the parathyroid gland, phosphorus can accumulate in the body and an excess can develop.

Similarly, hypofunction of the adrenal glands can lead to excess phosphate. In hypofunction, the adrenal glands can no longer produce enough of the steroid hormone aldosterone, which, like parathyroid hormone, ensures that the kidneys excrete enough phosphorus and that there is no phosphorus surplus.

Hyperthyroidism accelerates the metabolism of almost all cells in the body. The accelerated metabolism of the bone, especially bone resorption with release of phosphorus from the bone, can lead to phosphorus excess.

Lack of exercise has a similar effect: bones without exercise are less stressed, causing the body to break down more bone than it builds up, in addition to stabilising the built-up bone with phosphorus less effectively.

Malignant tumours can lead to an increased release of phosphorus from the bones. They form offshoots in the bone that dissolve the bone, or form substances that lead to increased bone breakdown. Phosphorus is released when bone is broken down. Malignant tumours are, for example, lung cancer, breast cancer, kidney cancer, leukaemia or malignant lymphomas.

A healthy person is unlikely to suffer from a phosphorus deficiency or excess because a healthy body can finely regulate the level of phosphate in the blood. However, if you are already suffering from a disease, a phosphate deficiency or excess may occur as a side effect. A deficiency can go unnoticed for a long time because the body relies on the phosphate bound in the bone. If you suffer from kidney insufficiency, the risk of phosphate excess is particularly high. But hypothyroidism or hyperthyroidism can also cause excess phosphorus. A simultaneously elevated calcium level can cause kidney and heart muscle calcification.