Moderate Egg Intake May Protect Brain Health

RRI.CO.ID. Jakarta - A new analysis from the Adventist Health Study-2 (AHS-2) finds that moderate egg consumption is associated with a significantly lower risk of Alzheimer’s disease. The study tracked 39,498 U.S. Seventh-day Adventists aged 65 and older for an average of 15.3 years, linking their dietary data to Medicare records to confirm clinical diagnoses.

During follow-up, 2,858 participants developed Alzheimer’s disease. Researchers used a validated food frequency questionnaire to assess egg intake, grouping participants from never/rarely eating eggs to 5 or more times per week.

After adjusting for demographics, lifestyle factors, other food groups, and comorbidities, any egg consumption was linked to a 17–27% lower risk compared with never/rarely eating eggs.

The hazard ratios showed a clear gradient: 0.83 (95% CI: 0.75, 0.92) for 1–3 times per month, 0.83 (0.74, 0.94) for once per week, 0.80 (0.71, 0.90) for 2–4 times per week, and 0.73 (0.60, 0.89) for 5 or more times per week. The strongest reduction was seen in those eating eggs most frequently.

Restricted cubic spline analysis supported a nonlinear relationship. Compared with an intake of 10 g/day, roughly one large egg per week, participants with zero egg intake had an adjusted hazard ratio of 1.22 (95% CI: 1.11, 1.34). This suggests that avoiding eggs entirely may be associated with higher risk.

The study accounted for many confounders that have limited earlier research. Models adjusted for BMI, physical activity, smoking, alcohol use, sleep, and intake of meat, fish, dairy, vegetables, fruits, grains, nuts, and legumes. Additional adjustments for cardiovascular disease, hypertension, diabetes, kidney disease, and other conditions did not change the association.

Biologically, eggs provide nutrients tied to brain health, including choline for acetylcholine synthesis, lutein and zeaxanthin for antioxidant protection, vitamin B12, and DHA. The authors note that deficiencies in choline and DHA have been found in the brains of people with Alzheimer’s disease. Substitution analyses also showed similar risk reductions when eggs were replaced with nuts/seeds or legumes.

While the study is observational and limited to a health-conscious U.S. cohort, the long follow-up, large number of clinically confirmed cases, and detailed dietary data strengthen the findings. The authors conclude that moderate egg consumption, as part of a balanced diet, may offer a potential neuroprotective benefit against Alzheimer’s disease.

Source : The Journal of Nutrition ( https://www.sciencedirect.com )