One extra year of school cut dementia cases decades later, a 100,000-person study finds

In 1957, the UK raised the school-leaving age from 15 to 16 — and accidentally ran one of the great natural experiments in brain health. Researchers analysed medical data from more than 100,000 UK Biobank participants, comparing people born just before and just after the reform's cut-off. Those who stayed the extra year were about 14% more likely to remain in school to 16 — and, followed to age 65, showed nearly one percentage point fewer cases of Alzheimer's disease and dementia, a large effect given how uncommon dementia is at that age. The protection was even stronger in people carrying high-risk genes for Alzheimer's. 'There are few preventative options out there, so even one could make a world of difference,' said lead researcher Silvia Barcellos of the University of Wisconsin–Madison. The study appears in the Proceedings of the National Academy of Sciences.

SDG 3 · Good health and well-being — Mechanism: policy reform