Using a hypothetical multivitamin as an example, in addition to other food sources, EFSA’s Panel on Food Additives and Nutrient Sources added to Food (ANS) found safety issues may arise.
By its formulation, ANS determined that overall daily methionine intake for all three forms would come to 12g for a 60kg person and that this “could be of safety concern”.
In regard to calcium, the ANS speculated that if calcium was taken at a level of 1200mg as calcium L-methionate, 9g methionine/day for an adult would be the resulting level, or 11.5g when other food sources were included. “The Panel has no data that demonstrate that such a level of methionine intake would be safe.”
If magnesium L-methionate was supplied at an upper limit of 250 mg magnesium/day, total intake methionate intake would come in at 5.5 g/day. Again it said it had “no data to prove that this would be a safe intake level for methionine.”
However if zinc mono-L-methionine sulphate was to be considered the sole source of zinc in food supplements at a level of 25mg zinc per day, ANS speculated methionate exposure to be 57.2 mg methionine/day and of “no safety concern”. It noted that zinc intakes may exceed upper limits, “especially for consumers at high percentiles.”
But it concluded, “that in the case of zinc mono-L-methionine sulphate the potential exposure to methionine and sulphate is negligible compared to the normal dietary intake of these compounds and that the use of zinc mono-L-methionine sulphate at the proposed level of use as a source of zinc is not of safety concern.”
Cautious
The calcium and magnesium dossiers were submitted by the UK Health Food Manufacturers’ Association (HFMA). The trade groups technical advisor, Michael Evans said ANS had focused on levels as opposed to the materials which had no inherent safety issues.
“ANS has taken a highly cautious approach as the levels of consumption they use as reference point are very high,” he told NutraIngredients.com. “But they are doing their job and they tend to be cautious in these matters.”
He said other substances present on Annex II of the Food Supplements Directive (FSD) also demonstrate safety issues if consumed at high doses.
Evans noted the methionate forms in question were not widely used in food supplements and that in submitting the dossiers, the HFMA sought to establish unique selling points for supplements that may incorporate the substances from other forms such as calcium carbonate and magnesium oxid.
But ANS’s negative opinion means it is unlikely the substances will be added to the FSD Annex II positive list of nutrients and will therefore become unavailable as nutrient sources.