This everyday food could reduce Alzheimer’s risk by 27% in people over 65

The egg is an everyday food that appears at almost every meal, yet rarely gets a second thought. And yet, a large study published in The Journal of Nutrition suggests that eating eggs regularly is associated with a lower risk of developing Alzheimer’s disease after the age of 65. Published in 2026, these findings have reignited scientific interest in one of the most familiar foods on our plates.

A study conducted on nearly 40,000 older adults

For their research, scientists analysed the dietary habits of 39,498 men and women aged at least 65, followed for just over fifteen years on average. The sheer scale of the cohort lends considerable weight to the observations made.

Over the course of the study, 2,858 participants received a diagnosis of Alzheimer’s disease. The researchers were therefore able to compare egg consumption habits between those who developed the condition and those who did not. This kind of long-term follow-up makes it possible to identify dietary trends over time.

This everyday food produced a notable statistical signal. The more frequently eggs were consumed, the lower the observed risk. The results show a steady progression according to weekly consumption frequency.

Figures that improve with consumption frequency

Compared with participants who never or very rarely ate eggs, the researchers observed a gradual reduction in risk. Eating eggs one to three times a month was associated with a 17% lower risk.

A frequency of two to four times a week was linked to a 20% reduction. Among those who ate eggs at least five times a week, that difference reached 27%. The trend appears to strengthen as consumption increases.

“This study establishes an association, not a direct cause-and-effect relationship. It does not allow us to claim that eating five eggs a week is enough to prevent Alzheimer’s.”

These figures should therefore be read with caution. It is also worth noting that the study participants belonged to a population that was particularly health-conscious, which may have influenced the results.

Why does this everyday food attract so much scientific attention?

Part of the answer lies in the yolk. It contains choline, a nutrient the body needs to produce acetylcholine, a neurotransmitter involved in memory, mood, and muscle control, among other functions.

Eggs also provide phospholipids and vitamin B12, two compounds that support cell function and the nervous system. These nutrients are concentrated in the yolk, which is often set aside in certain diets. Yet that is precisely where the bulk of this food’s nutritional value resides.

This everyday food therefore combines several components that are the subject of active research into brain health. Scientists are working to better understand the mechanisms by which these nutrients act on the ageing brain.

• Choline, found in the yolk, is used to produce acetylcholine, a neurotransmitter linked to memory.
• Phospholipids support the functioning of nerve cells.
• Vitamin B12 sustains the nervous system.
• Eating at least five eggs a week was associated with a 27% lower risk of Alzheimer’s in the study.
• The study followed 39,498 people aged at least 65 for more than fifteen years on average.

An association, not causation

It would be tempting to conclude that this everyday food directly protects the brain. However, the researchers are clear that their study establishes an association, not a direct causal link. That distinction matters if we are to avoid jumping to conclusions.

Furthermore, the study participants belonged to a health-conscious population. This factor can skew results, since these individuals often adopt other habits that are broadly beneficial to their health. The egg alone cannot account for all of the observations.

Brain health: a question of overall balance

This everyday food cannot, on its own, act as a shield against Alzheimer’s disease. Brain health depends on a far broader set of factors, overall diet, physical activity, sleep, cardiovascular health, and individual predispositions all play a role.

Every body also responds differently depending on its history, background, and lifestyle. A single food, however nutrient-rich, cannot compensate for wider imbalances. Brain nutrition research is advancing nonetheless, and each new study adds another piece to the puzzle.

What these findings do offer is a fresh perspective on an everyday food we so often consume without a second thought. They serve as a reminder that what we eat can play a role in brain health, provided it is part of a coherent, holistic approach. Science does not yet have all the answers, but it is pointing us in a direction.

The egg has thus reclaimed a serious place in scientific discussions on cognitive ageing. This everyday food, long reduced to its role as a breakfast staple, now deserves renewed attention from researchers and doctors alike.