A popular breakfast food could help lower the risk of a devastating neurodegenerative disease by as much as 27 percent, according to new research. Scientists have identified a link between regular egg consumption and a reduced chance of developing Alzheimer's disease, the most common form of dementia in the United Kingdom, affecting approximately half a million people.
Study Details and Findings
The study, published in The Journal of Nutrition, analysed data from nearly 40,000 older adults over a period exceeding 15 years. Participants were drawn from the Adventist Health Study-2, a project that enrolled more than 96,000 members of the Seventh-day Adventist church across the United States between 2002 and 2007. Adventists exhibit a wide range of dietary habits, from strict vegans who never consume eggs to omnivores who eat them daily.
Researchers categorised participants into five groups based on egg consumption frequency: never or rarely, one to three times per month, once per week, two to four times per week, and five or more times per week. A separate calculation also estimated total daily egg intake in grams, capturing eggs present in baked goods, mixed dishes, and recipes.
At the start of the trial, none of the 39,498 participants had been diagnosed with Alzheimer's disease. By the conclusion, 2,858 individuals had received a clinical Alzheimer's diagnosis. After adjusting for variables such as age, gender, education, weight, and other health conditions, the results revealed a clear trend: compared to those who never or rarely ate eggs, individuals who consumed eggs one to three times per month exhibited a 17 percent lower risk of Alzheimer's. Eating eggs once per week was associated with a similar 17 percent reduction. Consuming two to four eggs per week corresponded to a 20 percent lower risk, while those who ate five or more eggs per week showed a 27 percent lower risk.
Additional Analyses
A further analysis examined egg consumption as a continuous daily measurement rather than categorising participants into distinct groups. Using approximately one large egg per week as the baseline, the model revealed that individuals who consumed no eggs whatsoever faced a 22 percent elevated risk of Alzheimer's disease. The findings withstood multiple reliability checks. When all vegans were excluded from the analysis—given that vegans comprised a substantial proportion of the zero-egg cohort and typically differ in numerous lifestyle factors—the results remained virtually unchanged. The research team also performed substitution analyses, examining what would occur statistically if participants replaced their eggs with equivalent servings of nuts, seeds, or pulses. The egg-consuming groups continued to demonstrate reduced Alzheimer's risk, suggesting something distinctive about eggs themselves rather than simply consuming more protein-dense foods generally.
Nutrients in Eggs Linked to Brain Health
The researchers highlighted several nutrients concentrated in eggs that are tied to cognitive function. These include choline, a building block for a chemical messenger in the brain critical for memory, and a type of omega-3 called DHA, which helps maintain the structure and flexibility of brain cell walls. Deficiencies in both choline and DHA have previously been found in the brains of people with Alzheimer's disease.
Study Limitations
The study has limitations. Dietary intake was recorded only once at enrollment, meaning changes in eating habits over the years were not captured. However, researchers noted that about 74 percent of trial participants showed consistent egg consumption patterns when a follow-up comparison was conducted roughly a decade later. Additionally, the number of Alzheimer's diagnoses may have been undercounted, particularly among people with milder symptoms. It is also important to note that the analyses in this study were supported by an investigator-initiated grant from the American Egg Board. However, the study authors stated that the funding sources had no role in the study design, execution, data analysis, interpretation, manuscript preparation, or publication.
NHS Recommendations for Alzheimer's Prevention
The National Health Service (NHS) states that cardiovascular disease has been linked with an increased risk of Alzheimer's disease. Therefore, lowering your risk of cardiovascular disease could help prevent Alzheimer's. The health body recommends:
- Stopping smoking
- Keeping alcohol to a minimum
- Eating a healthy, balanced diet, including at least five portions of fruit and vegetables every day
- Exercising for at least 150 minutes every week by doing moderate-intensity aerobic activity (such as cycling or fast walking), or as much as you are able
- Making sure your blood pressure is checked and controlled through regular health tests
- If you have diabetes, make sure you keep to the diet and take your medicine
Other known risk factors for dementia include hearing loss, untreated depression, loneliness or social isolation, and a sedentary lifestyle.
