People who maintain sharp cognitive abilities into their 80s possess a distinct genetic advantage that appears to shield their brains from age-related decline, according to a new study from Vanderbilt University Medical Center. The research, published January 22, 2026, indicates that these "super agers" are significantly less likely to carry the APOE-ε4 gene variant, the strongest known genetic risk factor for late-onset Alzheimer's disease.

The study also revealed that super agers exhibit higher levels of the APOE-ε2 gene variant, which is associated with a reduced risk of developing Alzheimer's and is believed to offer some protection against the disease. Researchers compared the genetic profiles of super agers, defined as individuals over 80 with cognitive abilities comparable to those of people decades younger, with those of healthy seniors without such exceptional cognitive preservation.

"These findings help explain why some individuals are able to maintain youthful minds well into their 80s and beyond," said the lead researcher of the study. "The combination of fewer Alzheimer's risk genes and more protective ones appears to create a powerful buffer against cognitive decline."

The APOE gene provides instructions for making a protein that helps carry cholesterol and other fats in the bloodstream. Different versions of the gene, called variants, are associated with different risks of developing Alzheimer's disease. While APOE-ε4 increases the risk, APOE-ε2 is thought to be protective.

Experts emphasize that genetics are not the sole determinant of cognitive health. Lifestyle factors, such as diet, exercise, and cognitive engagement, also play a crucial role. However, this study highlights the significant contribution of genetic predisposition to maintaining cognitive sharpness in advanced age.

The findings have practical implications for understanding and potentially mitigating the risk of Alzheimer's disease. Future research may focus on developing therapies that mimic the protective effects of the APOE-ε2 variant or target the mechanisms by which APOE-ε4 increases Alzheimer's risk. This could lead to new strategies for preventing or delaying the onset of the disease, ultimately helping more people maintain their cognitive abilities as they age.