THURSDAY, July 30, 2026 (HealthDay News) — Feeding your toddler — or unborn child — less sugar might protect their brains from dementia much later in life, a new study says.

Children who endured World War II sugar rationing had an up to 23% lower risk of dementia in old age, compared to those born after rationing ended, researchers reported July 29 in the journal Neurology.

“Our findings suggest that limiting sugar during the earliest stages of life may have lasting benefits for brain health,” lead researcher Jiazhen Zheng said in a news release.

“These results highlight the potential importance of early-life nutrition in reducing the risk of dementia decades later,” Zheng said. He is a researcher at Hong Kong University of Science and Technology in Guangzhou, China.

For the new study, researchers tracked nearly 65,000 U.K. residents who were born before and after World War II sugar rationing. Sugar only became widely available again in the U.K. after 1953, the team said.

Results showed that people who experienced sugar rationing prior to birth and up to 1 year of age had a 21% lower risk of dementia, and those who endured sugar rationing up to two years old had a 23% lower risk.

For people with lower sugar levels earlier in life, dementia was delayed by nearly three years, researchers found.

Brain scans showed that people exposed to less sugar early in life had higher total volume of gray matter, and fewer white matter scars that are a marker of brain tissue damage.

“Limiting added sugars during pregnancy and infancy may be one beneficial step that families and communities can take, but further research is needed to better understand how these early exposures influence dementia risk and to guide public health strategies,” Zheng said.

More information

Harvard Medical School has more on dementia risk factors.

SOURCE: American Academy of Neurology, news release, July 29, 2026