Alzheimer disease has a complex etiology composed of nutritional and genetic risk factors and predispositions. Moreover, genetic risk factors for cognitive decline may remain latent pending age-related decline in nutrition, suggesting the potential importance of early nutritional intervention, including preventative approaches. We hypothesized that a combination of multiple nutritional additives may be able to provide neuroprotection. We demonstrate herein that dietary supplementation with a mixture of ALA, ALCAR, GPC, DHA, and PS reduced reactive oxygen species in normal mice by 57% and prevented the increase in reactive oxygen species normally observed in mice lacking murine ApoE when maintained on a vitamin-free, iron-enriched, oxidative-challenge diet. We further demonstrate that supplementation with these agents prevented the marked cognitive decline otherwise observed in normal mice maintained on this challenge diet. These findings add to the growing body of research indicating that key dietary supplementation may delay the progression of age-related cognitive decline.