Daily egg may protect brain health in older adults
New study finds a 10% fall in cognitive decline with regular egg intakes
Eating an egg a day could help support brain health and reduce the risk of cognitive decline in older adults, according to a new study published in the Journal of Human Nutrition and Dietetics [i].
The large systematic review and dose–response meta-analysis examined evidence from 21 observational studies which explored the relationship between egg consumption and cognitive function. The studies involved almost 100,000 adults from different countries.
Delving into the data, researchers analysed more than 18,000 cases of cognitive impairment, finding that moderate egg intake—around 50 grams per day, equivalent to one medium egg—was associated with a significantly lower risk of cognitive decline. Protective associations were particularly evident in longer-term studies and in people aged over 60 years.
The analysis showed that people consuming a daily egg had a 9% lower risk of cognitive decline compared with those eating the least eggs. Researchers also observed a “U-shaped” relationship, suggesting that moderate intakes of 1-2 eggs a day were in the beneficial range while very high intakes did not provide additional protection. The research supports an earlier study linking regular egg intake to a 40% lower risk of dementia [ii] and a research [iii] report showing that the unique blend of nutrients in eggs can help brain development and function during pregnancy, early childhood, and adolescence.
Dietitian Dr Carrie Ruxton comments: “Eggs are one of nature’s most nutrient-dense foods and provide several key nutrients linked to brain health, including choline, B vitamins, high-quality protein and healthy fats. These nutrients support neurotransmitter function and help maintain the structure of brain cells.
“Choline, in particular, is essential for the production of acetylcholine, a neurotransmitter involved in memory and learning. As eggs are one of the few natural sources of choline, this could explain why eating eggs is linked with better cognitive health.”
Cognitive decline, which can affect memory, attention and decision-making, is becoming increasingly common as populations age. The NHS [iv] estimates that one in 11 adults aged over 65 years lives with dementia, a progressive form of cognitive impairment. Low choline and vitamin B12 levels in the blood have been linked with worse cognitive performance in older adults [v].
Dr Ruxton adds: “The new research confirms that including eggs in the daily diet is simple and affordable way for older adults to help support their brain health. Because eggs contain a unique combination of nutrients important for the brain, they can be a valuable part of a healthy ageing diet alongside fruit, vegetables, wholegrains and oily fish. How you eat your eggs is also important with boiled, poached and scrambled eggs a better option than a fry up”.
[i] Egg Consumption and Cognitive Function: A Systematic Review and Dose-Response Pooled Analysis Exploring Optimal Daily Intake - PubMed
[ii] Association of Egg Intake With Alzheimer's Dementia Risk in Older Adults: The Rush Memory and Aging Project - PubMed
[iii] Derbyshire E (2026) Eggs and Associated Nutrients: Implications for Brain Development and Function From Conception to Early Adulthood: A Narrative Review. Nutrition Bulletin 0: 1-21. Available at: https://onlinelibrary.wiley.com/doi/10.1111/nbu.70042
[v] Plasma free choline, betaine and cognitive performance: the Hordaland Health Study - PubMed