This document discusses the link between docosahexaenoic acid (DHA), an omega-3 fatty acid found in fish, and Alzheimer's disease. DHA is highly concentrated in the brain and is important for brain development, function, and maintenance of cognitive abilities. Epidemiological studies have shown that increased consumption of DHA and other omega-3 fatty acids can reduce the risk of dementia. Low levels of DHA have been associated with increased risk of cognitive impairment and depression. Taking DHA supplements has been shown to slow the progression of Alzheimer's symptoms and depression. Maintaining healthy levels of DHA through diet and supplements may help prevent Alzheimer's and support brain health.