WASHINGTON, DC—Nonpharmacologic interventions such as a healthy diet, aerobic exercise, and socialization may lower the risk for dementia, reported Gary Small, MD, at the 2008 Alzheimer’s Disease Summit.
Beyond Standard Antidementia Therapy
According to Dr. Small, a brain-healthy diet includes antioxidant fruits and vegetables, omega-3 fatty acids, and low glycemic index carbohydrates. High-antioxidant foods include blueberries, broccoli, plums, prunes, raisins, and spinach. Examples of desirable omega-3 fats are avocados, green leafy vegetables, herring, lean meats, nuts, olive oil, salmon, and tuna. Foods rich in omega-6 fats—such as bacon, butter, donuts, French fries, lamb chops, mayonnaise, steak, and whole milk—should be avoided, said Dr. Small. In addition, he recommended that older persons take a daily multivitamin, because many people as they age are not able to absorb all nutrients in food. Dr. Small is Director of the University of California, Los Angeles, Center on Aging.
Caloric intake should be moderate to avoid illnesses associated with obesity, noted Dr. Small. He cited a study of 939 persons older than 65 who did not have dementia, in which the only dietary variable associated with a higher risk for Alzheimer’s disease was total calories; the study found no association between glycemic load and Alzheimer’s disease.
Dr. Small also advocated exercise for the determent of Alzheimer’s disease. Research has found that physically active adults have a lower risk for Alzheimer’s disease than do inactive people. In addition, active laboratory animals have more hippocampal memory cells than do inactive controls, and cardiovascular fitness is associated with greater parietal, temporal, and frontal cortical tissue. Cardiovascular conditioning can also improve frontal lobe function.
According to Dr. Small, social disengagement is a risk factor for cognitive impairment among older persons. A community-based Swedish cohort of 1,203 nondemented people followed for three years found that a poor or limited social network increased the risk for dementia by 60%.
Healthy Lifestyle Intervention Program
Dr. Small and colleagues conducted a six-week healthy lifestyle intervention in older adults and found measurable improvement in immediate memory of unrelated word pairs, recognition of words after a delay, and ability to generate or remember more words. The memory fitness program included 60-minute classes, held twice a week, with 15 to 20 participants. Information and exercises focused on stress reduction, increased daily exercise, diet/nutrition tips, and memory techniques such as Name-Face Association, Chunking/Categorization, Everyday Memory Skills, Look-Snap-Connect, and Story Method. A similar two-week study found a 5% decline in resting left dorsolateral prefrontal cortex activity on 18fluorodeoxyglucose PET, suggesting improved cognitive efficiency.
“If we accept the assumption that simple lifestyle choices improve brain health and lower the risk for Alzheimer’s disease, then changing everyday habits could have an impact on the future prevalence of dementia,” said Dr. Small. “For example, eating fish once a week, daily cognitive activities such as reading, games, and crossword puzzles, and ingesting antioxidant foods could decrease the expected prevalence of dementia by one million cases within five years. Additional research is needed to determine the role of dietary supplements in lowering the risk for dementia.
—Andrew N. Wilner, MD