Martha Clare Morris, Sc.D. is an Associate Professor in the Department of Internal Medicine and the Rush Institute for Healthy Aging, Assistant Provost for Community Research, and Director of Nutrition and Nutrition Epidemiology at Rush University Medical Center. She received her bachelors and Master of Science degrees in Sociology at the University of Iowa, and her doctorate in Epidemiology at the Harvard School of Public Health in 1992.
She is the Epidemiologist of a large population-based study of risk factors for the development of Alzheimer’s disease, cognitive decline, and other problems of older persons. The ongoing study called the Chicago Health and Aging Project began in 1993 and includes over 9,000 residents aged 65 years and older living on the south side of Chicago. Since 1996 she has been funded by the National Institute on Aging to investigate dietary risk factors for Alzheimer’s disease and cognitive decline. The study has generated numerous findings of dietary associations, including lower risk of Alzheimer’s’ disease and slower rate of cognitive decline with high intake of vitamin E in food, consumption of fish and n-3 fatty acids, and dietary fat composition that is low in saturated and transunsaturated fats and high in vegetable fats.
Epidemiologic Evidence of Antioxidant Nutrients and Brain Health
Huang, T.L. Ph.D., Tangney, C.C., Ph.D. Li, Hong, MS., Kwasny, M., Ph.D.,
Morris, M.C., ScD
Section of Nutrition Epdiemiology
Rush University Medical Center, Chicago, Il
Context: Flavonoids have been reported to improve learning and memory by an enhancement of neuronal function, protection of vulnerable neurons and promotion of neurogenesis.
Objective, Outcome, Sample and Design: We examined the effects of flavonols (quercetin, kaempferol, and myricetin) and flavones (apigenin, luteolin), total flavonoids and strawberries on change in cognitive function over five cycles for a total of 15 years among participants of the ongoing prospective study known as the Chicago Health and Aging Project (CHAP). These analyses were performed on 3774 participants, 60% black, aged 65 years and older. Change in cognitive function is based on the average z-score of four tests: the East Boston Tests of immediate memory and delayed recall, the Mini-Mental State Examination, and the Symbol Digit Modalities Test.
Results: Using mixed linear models adjusted for sex, education, age, race and cognitive activity, we found significant protective effects with quercetin, kaempferol, flavonols, total flavonoids and strawberries on cognitive decline. After examining possible interactions with each of the flavonoids with sex, education, age and race, we found a significant effect with race There was a 26.1% reduction in the rate of decline among black persons in the highest quintile (mean: 24.7 mg/d) of total flavonoid intake compared with those in the lowest quintile (mean: 6.2mg/d) (p =.02) in the multivariable model.
The reductions in rate of decline with total flavonols, quercetin and kaempferol was 34.8% (p= 0.005), 23.4% (p=0.022) and 29.3% (p= 0.011), respectively. With strawberries, those who consumed more than 1 serving of strawberries per month had a slower rate of cognitive decline vs. those who consumed less. With strawberries, the rate of decline was modified by gender, but not with race. Females who consumed more than 1 serving of strawberries per month had a 16.2% slower rate of cognitive decline (p=0.0009); males had non-significant increased rates of decline.
Conclusion: Specific flavonols (quercetin and kaemferol) and strawberries may be associated with a slower rate of cognitive decline with older age.