Introduction: Dementia affects over 5 million Americans and 35 million people worldwide. This clinical review looked at whether there is an association between the intake of vitamins, minerals, and herbs, and cognitive function and the onset of dementia. Methods: A search of Medline, Cochrane Library, and the National Center for Complementary and Integrative Health revealed 18 articles related to nutrition, cognitive decline, and the onset of dementia. Findings: Daily consumption of at least three servings of vegetables that contain antioxidants, such as vitamins B, C and E, are effective in delaying the decline of cognitive function. Individuals who adhere to the Mediterranean diet, which emphasizes fruits, vegetables, whole grains, legumes and nuts, have a slower progression toward the onset of dementia. Conclusion: Dementia is a progressive disease that can be delayed by adequate intake of specific nutrients, which are most beneficial when acquired through whole foods rather than dietary supplements.