The salt is preferably salt of Manganese, and most preferably Manganese Chloride (MnCl2).

Magnesium chloride, calcium chloride, zinc chloride and/or manganese chloride are used as multivalent salt components.

Manganese chloride did not produce somatic mutations in D. melanogaster (Rasmuson, 1985).

Soluble manganese (e.g., manganese chloride) is more readily absorbed (Roels et al., 1997), as is the complex-associated trivalent oxidation state of manganese found in human milk.

Preferably, said active agents are alpha hydroxyl acids or alpha ceto acids or salts and esters of said acids or manganese chloride.