Alzheimer’s disease is the most common form of dementia, affecting over 720,000 people in the UK — a number expected to rise sharply as the population ages.

It causes gradual memory loss, confusion, and difficulty with everyday tasks. While there’s no cure, research increasingly points to diet and lifestyle as key areas for prevention.

Now, a new study suggests that eating eggs — even just once a week — may be linked to a significantly lower risk of developing Alzheimer’s disease.

Published in the Journal of Nutrition, the study tracked 1,024 older adults in the United States over nearly seven years.  Researchers found that those who ate more than one egg a week were 47% less likely to develop Alzheimer’s compared to those who ate fewer or none.

The key nutrient? Choline — found in high amounts in egg yolks — which supports memory, mood, and nerve signalling in the brain.

What Did the Study Show?

• Risk cut by 47%: Older adults who consumed more than one egg per week had a 47% lower risk of Alzheimer’s.

• Choline was key: This essential nutrient explained around 39% of the protective association observed.

• Other beneficial nutrients: Eggs also contain omega-3 fatty acids, which have known neuroprotective effects, as well as vitamin B12 and D.

Importantly, the study was observational — meaning it shows an association, not a direct cause. But the findings align with a growing body of research linking diet to long-term brain health.

“This study adds to the growing body of evidence that dietary choices can have a significant impact on reducing the risk of Alzheimer’s dementia and supporting lifelong cognitive health.”

— Dr Taylor Wallace, lead researcher and Adjunct Associate Professor, Tufts University.

What Is Choline and Why Does It Matter?

Choline is a vitamin-like nutrient that plays a key role in maintaining healthy brain function. It helps the body produce acetylcholine — a neurotransmitter important for memory and learning.

Many people in the UK may not be getting enough. According to the British Nutrition Foundation, average intakes of choline are below recommended levels for some age groups.

One large egg contains around 125 mg of choline — roughly a quarter of the daily recommended amount for adults.

Other Brain-Friendly Nutrients in Eggs

Eggs also provide:

• Omega-3 fatty acids – support brain structure and reduce inflammation

• Vitamin B12 – helps prevent cognitive decline and supports nerve function

• Vitamin D – important for brain and immune function

• Iodine and selenium – essential trace minerals for neurological health

According to NHS guidance, these nutrients all play roles in keeping the brain healthy, particularly as we age.

“Eggs are one of the few commonly consumed foods that are naturally rich in choline, a nutrient that we are researching to further understand its role in supporting both cognitive development in infants and young children and maintenance during the aging process.”

— Dr Taylor Wallace

Should You Start Eating More Eggs?

Eggs are affordable, easy to cook, and widely available — and they provide many of the nutrients needed to support brain health.

That said, moderation is key. The NHS advises up to seven eggs a week as part of a healthy, balanced diet. While eggs are low in saturated fat, how you prepare them matters — boiling or poaching is healthier than frying.

A Final Word

Alzheimer’s disease is a growing concern as we live longer — but this study adds to the growing evidence that what we eat can make a real difference.

Including eggs as part of a balanced, varied diet may be one small but meaningful step to support lifelong brain health. And as always, it’s the whole pattern of eating that matters most — not just one food on its own.