Written by Chrystal Moulton, Staff Writer. Higher consumption of whole grain was protective for African American participants in global cognition (p trend= 0.004), perceptual speed (p trend= 0.03), and episodic memory (p trend= 0.01).
Whole grain consumption has previously been associated with cognitive benefits1,2. However, much of the research on the cognitive benefits associated with diet was conducted in predominantly Caucasian individuals3. Results from such studies are not easily generalized to other racial cohorts. Studies have shown that consumption of plant-based items differ significantly between African Americans and Caucasian individuals. In the current study, researchers investigated the association between whole grain consumption and overall cognitive decline in older African American and Caucasian participants3.
This was a longitudinal, population-based study of Alzheimer’s disease and dementia among individuals 65 years or older. Formally known as the Chicago Health and Aging Project, this study started in 1993 and identified eligible participants from 1993 to 1997 (n=6158) who willingly participated in an in-home interview. During the interview, researchers collected demographic data, health status, and conducted physical and cognitive performance tests. The interviews were conducted every 3 years for 18 years (maximum 6 times). Four cognitive assessments were conducted at each in-home interview measuring episodic memory, perceptual speed, and overall cognitive ability. Results from the cognitive tests were represented as a summary of all for assessments. A food frequency questionnaire was used to measure whole grain and refined grain consumption. Researchers used information from 1990 census data to collect sociodemographic information. Chronic disease and health information was provided by the participants. Investigators used this information to compare consumption of whole grains (divided into quintiles) with cognitive decline over time. For the purposes of this analysis, only participants who completed the food frequency questionnaire, ≥2 cognitive assessments, as well as a ApoE genotype assessment were included. Researchers only used 10years of follow up data for this analysis.
African American participants made up 62% of the total participants in the Chicago Health and Aging Project, while Caucasian Americans made up 38% of volunteers. Researchers excluded data from participants who didn’t complete more than 50% of the food frequency questionnaire, who had extreme BMI (either extremely low or high), and who scored ≤10 on the Mini Mental State Examination (tests current cognitive status). Data from 3,326 participants were included in this study. Results showed that African American participants consumed more whole grains than their Caucasian counterparts. They also had a higher proportion of people with the ApoE genotype who consumed high amounts of whole grains. Statistical analysis revealed that individuals in the highest quintile of whole grain consumption had lower cognitive decline compared to those in the lowest quintile (p= 0.013). Participants in the highest quintile also showed significantly slower rate of decline in episodic memory (p= 0.08) and perceptual speed (p= 0.026). Additionally, researchers found that higher consumption of whole grain was protective for African American participants in global cognition (p trend= 0.004), perceptual speed (p trend= 0.03), and episodic memory (p trend= 0.01). However, for Caucasian participants (n=1,249), consumption of whole grains did not attenuate decline in global cognition, episodic memory, and perceptual speed. When adjusting for BMI, Mini Mental State Examination, and physical activity, the association between whole grain consumption and attenuation of cognitive decline in African Americans remained unchanged. African Americans in the highest quintile of whole grain consumption were approximately 8.5 years younger in their cognitive abilities compared to those in the lowest quintile. Interestingly, however, the average consumption of whole grains in this study was only half of what is recommended by the FDA.
Results from this analysis revealed the importance of consuming whole grains daily, especially among African Americans. Additional studies assessing whole grain consumption in other minority groups and its association with cognitive decline will be needed to determine a targeted nutritional approach for reducing mental decline in older adults.
Source: Liu, Xiaoran, Todd Beck, Klodian Dhana, Pankaja Desai, Kristin R. Krueger, Christy C. Tangney, Thomas M. Holland, Puja Agarwal, Denis A. Evans, and Kumar B. Rajan. “Association of Whole Grain Consumption and Cognitive Decline: An Investigation From a Community-Based Biracial Cohort of Older Adults.” Neurology 101, no. 22 (2023): e2277-e2287.
© 2023 American Academy of Neurology
Click here to read the full text study.
Posted January 4, 2024.
Chrystal Moulton BA, PMP, is a 2008 graduate of the University of Illinois at Chicago. She graduated with a bachelor’s in psychology with a focus on premedical studies and is a licensed project manager. She currently resides in Indianapolis, IN.
References:
- Călinoiu LF, Vodnar DC. Whole Grains and Phenolic Acids: A Review on Bioactivity, Functionality, Health Benefits and Bioavailability. Nutrients. Nov 1 2018;10(11)doi:10.3390/nu10111615
- Ndolo VU, Beta T. Distribution of carotenoids in endosperm, germ, and aleurone fractions of cereal grain kernels. Food Chem. Aug 15 2013;139(1-4):663-71. doi:10.1016/j.foodchem.2013.01.014
- Liu X, Beck T, Dhana K, et al. Association of Whole Grain Consumption and Cognitive Decline: An Investigation From a Community-Based Biracial Cohort of Older Adults. Neurology. Nov 28 2023;101(22):e2277-e2287. doi:10.1212/wnl.0000000000207938
