Study: phosphorus claim could present public health risk

A paper to be published in the journal Food Policy raises concerns that some general function health claims soon to be authorised in the European Union could put public health at risk.

The paper, written by Igor Pravst of the Nutrition Institute in Slovenia, voices particular concerns about the claim linking phosphorus to bone and dental health, on the basis that it will lead to ‘phosphorus loading’, which could have a negative effect on bone health.

EFSA (European Food Safety Authority) is currently completing evaluation of general function claims and the European Commission’s authorisation of those with a favourable outcome is expected by the end of 2011.

For many essential nutrients, there is strong consensus among scientific experts that a cause-and-effect relationship has been established. When considering claims for these nutrients, it is thought that EFSA will rely on such a consensus without reviewing the primary scientific studies on the claimed effects.

Pravst warns that this approach could result in health issues with certain nutrients being overlooked.

He is particularly concerned about the claim relating to phosphorus, as he says there is evidence to suggest that increasing dietary intakes above current values might have negative effects for bone structure.

“There are quite a few papers dealing with the problem of excess phosphorus intakes,” Pravst told NutraIngredients. “They have shown that if you have too much phosphorus, the body’s absorption of calcium decreases, which could have a negative impact on bone structure.”

An adequate phosphorus intake is needed for normal bone growth and development in children and for maintaining normal bone in adults. However, according to Pravst, the health claim evaluation process found no evidence of an inadequate phosphorus intake in the general EU population.

“The mean daily phosphorus intake of adults in European countries ranges between 1017 and 1422 mg...well above the current recommendations of about 700 mg/day,” he wrote in the paper.

“The use of health claims concerning phosphorus and its contribution to the maintenance of normal bone might not only encourage consumers to consume more phosphorus-rich foods, but also stimulate producers of foods and food supplements to increase phosphorus contents to a level that would enable such claims to be made.

Both health and ethical concerns arise as to whether such claims should be allowed and whether there is evidence of potential negative effects of a higher phosphorus intake, even though science is not yet clear on this issue.”

Pravst is urging the Commission to attach specific conditions of use to the claim that would prevent its use in fortified foods and food supplements.

"This solution would not provide food producers with motives to boost phosphorus content in foods, while they would simultaneously be able to use the claim on food naturally rich in this nutrient,” he said.

Pravst says that a similar situation exists with some other nutrients. For example, with regards to claims related to chloride as Na-, K-, Ca-, or Mg-salt and its contribution to digestion by production of hydrochloric acid in the stomach, he said:

“I’m afraid this may encourage manufacturers to include sodium chloride in products.”

Pravst has written to the Commission about both the phosphorus and the chloride issue. His letter on chloride has also been accepted for publication in the British Journal of Nutrition.

Source: Food Policy

Published online ahead of print, doi: 10.1016/j.foodpol.2011.05.005

“Risking public health by approving some health claims? – The case of phosphorus.”

Author: Pravst, I.