The effect of dietary methionine on the copper content of tissues and survival of young and old mice

We tested the possibility that methionine might improve the lifespan of male C57BL/6J mice, based upon the ability of methionine to chelate copper. Old mice given 0.05M methionine in their drinking water for 42 days had lower brain copper concentrations (p less than 0.05). The decrease in liver, kidney, and heart copper was not significant when compared to unsupplemented controls. The lifespan of old mice was unchanged by feeding 0.05M methionine. Young mice, however, experienced a 16.9% decrease in their average lifespan and a decreased maximum lifespan when given supplemental methionine. We conclude that dietary supplements of methionine may be useful for removing copper from the brain but they also can increase the rate of senescence in mice.