Antioxidantes

O que são antioxidantes?

Os antioxidantes são moléculas que interagem com os radicais livres altamente reativos, sendo que estes últimos existem como resultado de vários processos que ocorrem diariamente no nosso organismo. Os antioxidantes limpam os radicais livres, que são depois estabilizados através de um sistema de ressonância aromática, gerando radicais estáveis.

O organismo produz alguns antioxidantes. Contudo, depende de fontes externas para obter os restantes antioxidantes de que precisa. Estes antioxidantes exógenos são normalmente designados por antioxidantes alimentares e podem ser obtidos sobretudo a partir de fruta, legumes e cereais. Os antioxidantes alimentares também estão disponíveis sob a forma de suplementos alimentares.

Entre os antioxidantes mais comuns incluem-se betacaroteno, licopeno, polifenóis, vitamina A, vitamina C e vitamina E (alfa-tocoferol).

Vários estudos científicos demonstram que os antioxidantes:

Atuam na prevenção das reações oxidativas
Desempenham um papel na proteção celular contra os danos causados pelos radicais livres

Referências

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