Ischemic heart disease remains the leading cause of death in the USA. Statins have substantially contributed to the decline in mortality due to heart disease. Historically, statins are hypothesized to be neuroprotective and beneficial in dementia, but recent reports have suggested an association with transient cognitive decline. We have critically appraised the relationship between statins and cognitive function in this review. Most of the data are observational and reported a protective effect of statins on dementia and Alzheimer's disease in patients with normal cognition at baseline. Few studies, including two randomized control trials, were unable to find a statistically significant decrease in the risk or improvement in patients with established dementia or decline in cognitive function with statin use. As more randomized control trials are required to definitively settle this, cardiovascular benefits of statins must be weighed against the risks of cognitive decline on an individual basis.