However, phosphates are generally present in nature at low levels, because the only primary source is the slow erosion of rocks. Phosphorus is often thus “limiting” for plant growth. For this reason, human civilisations in the past had to make considerable efforts to ensure that phosphate supply to agriculture was maintained, by collecting and returning animal and human wastes to land. Today, man ensures phosphorus supply to crops by extracting phosphates from natural rock, to produce phosphate fertilisers.

Food phosphates are also made from phosphate rock, after intensive purification. Heat combination with different mineral salts (sodium, potassium, calcium, magnesium or iron) produces a wide range of specific compounds for different purposes. Nearly all phosphates extracted from rock are used in fertilizers, detergents or agricultural animal feed supplements, and only around 1% is used by the food phosphate industry. Modern diets usually contain largely adequate levels of phosphate for human health, so food phosphates are not generally used as a dietary additive. They are used for a range of purposes including maintaining natural colours and flavours, acidity buffering, leavening, stabilisation of texture, shelf-life quality, and as a support for calcium, magnesium and iron mineral enrichments.

In the body, they are broken down to simple phosphate ions (PO4), the basic building block of the many different biological molecules which include phosphorus. Excess phosphate is excreted by the kidneys when dietary intake exceeds the body`s needs. Food phosphates have been used safely for over 100 years. The European Union`s Scientific Panel on Dietetic Products, Nutrition and Allergies assessed food phosphates in 2005 i, within its ongoing studies of vitamins and minerals. The Committee concluded that there is no evidence of adverse effects.