Sugar Rationing in Early Childhood Linked to Lower Dementia Risk Decades Later

Eating too much sugar during the first 1,000 days of life — from conception through age two — may be associated with a higher risk of developing dementia decades later, scientists report in the Aug. 25 issue of Neurology. "The first 1,000 days are critical for brain development," when the brain undergoes exceptionally rapid growth and neuronal development, said epidemiologist Jiazhen Zheng of the Hong Kong University of Science and Technology in Guangzhou, China.

Zheng and colleagues examined health records of nearly 65,000 people in the UK Biobank who were in utero, infants or toddlers between July 1942 and June 1954. During those years, a British government policy set a daily limit on the amount of sugar a person could purchase — a World War II austerity measure that allowed each person 41 grams of sugar a day, roughly the amount in a 12-ounce can of Coke today.

After adjusting for lifestyle, socioeconomic status and other conditions, the team found that people who lived through their first two years under sugar rationing had a 23% lower risk of developing dementia and a 28% lower risk of developing Alzheimer's disease than those born after the rationing policy ended, with a similar reduction among those rationed for just their first year. Among those who did develop either condition, the disease appeared almost three years later, on average, than in people never subject to rationing.

Zheng cautioned that other factors beyond sugar consumption may also have played a role, so he cannot say how much sugar is safe to consume to reduce risk. Still, he said, families should limit added sugars in children's diets — the Dietary Guidelines for Americans recommend no added sugars at all before age 11. "That's one of the best things they can do, a sensible step for children's overall health," he said.