One extra year of school was associated with fewer dementia diagnoses decades later, according to a study using data from more than 100,000 UK Biobank participants. The research was published in the Proceedings of the National Academy of Sciences and reported in October 2026.

The researchers used a 1972 reform in England, Wales and Scotland that raised the minimum school-leaving age from 15 to 16. The change applied to students born on or after 1 September 1957, while those born just before that date could still leave at 15. That sharp dividing line allowed researchers to compare people born days apart who faced different schooling rules.

What the study found

The reform increased the share of students staying in school until at least age 16 by 14 percentage points. Over the following 50 years, the additional year was associated with a 0.88% reduction in Alzheimer's disease and related dementia incidence, based on diagnoses recorded up to December 2022, when the oldest participants turned 65.

The effect was strongest among participants carrying genetic variants linked to higher dementia risk. The authors urge caution, however, because participant age was capped at 65, when dementia remains relatively uncommon, and differences between groups may change as the cohort ages. The study also linked the reform to improvements in socioeconomic factors and other areas of health.

Sources: Phys.org, MedicineNet / HealthDay