Informe del Comité Científico de la Agencia Española de Seguridad Alimentaria y Nutrición (AESAN) en relación a la evaluación del riesgo de la ingesta inadecuada de minerales (metales) antioxidantes en complementos alimenticios que puede dar lugar a efectos prooxidantes: cobre, manganeso, selenio y zinc

Abstract

The term antioxidant generally refers to the property of some substances to prevent oxidative damage. Oxidative stress is one of the etiopathogenic mechanisms of a large number of pathologies with high prevalence in our society, and numerous studies have been directed in recent years to demonstrate the beneficial properties of the intake of compounds with antioxidant potential, promoting and encouraging their consumption. Therefore, consumer interest in the use of substances with antioxidant properties and the supply of foods and food supplements with alleged antioxidant effects have increased considerably. On the other hand, some antioxidants have shown contradictory behaviours since, in certain doses or conditions, they can become prooxidants. The divalent metals copper, manganese, selenium and zinc have been demonstrated to contribute to the protection of cells against oxidative damage by acting as cofactors of antioxidant enzyme systems. These minerals have approved health claims related to the protection of cells against oxidative damage under the European regulatory framework. The supplementation of copper, manganese, selenium and zinc through fortified foods and food supplements in the healthy adult population is safe under the conditions laid down by European regulations. On the other hand, scientific literature suggests that these metals could have prooxidant effects in certain doses or conditions. It is recommended that studies be carried out with an adequate methodology to evaluate these effects thoroughly and under which conditions they occur, as well as the adverse effects that could derive from them. In addition, for pregnant or lactating women, children, the elderly and people with certain pathologies, supplements should only be taken after consultation with a health professional since there is little information on the safety of many substances in these stages and, sometimes, there may be interactions with medications. In no case should they replace the use of medicines without proper medical supervision. The maximum amounts of minerals that could be used in food supplements per daily intake as recommended by the manufacturer, as well as the amount that could be added to foods, should be established taking into account the maximum safe levels of vitamins and minerals and the intake of vitamins and minerals from other food sources, as already provided for in Directive 2002/46/EC on food supplements and Regulation (EC) No. 1925/2006 on the addition of vitamins and minerals and of certain other substances to foods.