Approximately two out of every three American adults will experience some level of cognitive impairment by the age of 70. However, a recent study suggests a simple solution for staving off cognitive decline: eating eggs.
The research, published recently in the journal Nutrients, found a link between egg consumption and better semantic memory and executive functioning in women.
“Prior literature on the association of dietary cholesterol levels with cognitive function is inconsistent, with some studies showing a negative effect, others showing a positive effect, and still others showing no effect,” said Donna Kritz-Silverstein, PhD, the study’s principal investigator and a professor in the School of Public Health and Department of Family Medicine at the University of California, San Diego.
The inconsistency paved the way for the study group to examine whether egg consumption was related to change in cognitive performance over four years in a large sample of community-dwelling older men and women, she said.
Limitations of the Study
The generalizability of the study’s results may be limited due to the homogeneity of the Rancho Bernardo Study participants who are predominantly white, highly educated, and can afford access to medical care,” Kritz-Silverstein said.
However, the study notes that this homogeneity may illustrate that factors such as culture, education, the ability to afford medical care, and lifestyle choices are less likely to influence the results.
The research also relied on self-reported information, which is more likely to be inaccurate, and it didn’t explore the mechanism behind how eggs may benefit cognition—though the study noted that they contain several nutrients known to support brain health, such as protein, choline, and carotenoids like lutein and zeaxanthin.
Future research into the cognitive benefits of eggs should include imaging to show whether cognitive performance is consistent with observed changes in the brain, Kritz Silverstein noted.
More Eggs, Better Cognitive Health
To test the effects of eggs on cognitive functioning, researchers pulled data on 890 adults (357 men and 533 women) who participated in the Rancho Bernardo Study, a long-term community-based observational cohort study. All participants were over 55, and the average age was between 70 and 72.
Participant egg intake was assessed between 1988 and 1991 through food frequency questionnaires. Researchers also gave participants performance tests between those years examining global cognitive functioning, such as language, orientation, attention, recall, executive function, mental flexibility, and visuomotor tracking. Those skills were reassessed between 1992 and 1996, with the average time between visits being about four years.
The researchers found that 14% of men and 16.5% of women reported never eating eggs. In contrast, 7% of men and nearly 4% of women reported consuming eggs over five times per week.
Generally, men had higher rates of egg consumption than women, being more likely to consume them two to four times or more than five times weekly. Women were more likely to either not eat eggs or eat one to three per month.
AMANI Nesta