Less sugar early in life might decrease dementia risk

Parents of toddlers know too well what sugary treats can do. Kids can buzz with energy initially, only to crash or have mood swings later. Now a new study provides more evidence that excess sugar in early life could also pose health problems much later.

Eating too much sugar during the first 1,000 days of life may be associated with a higher risk of developing dementia decades later, scientists report in the Aug. 25 Neurology.

“The first 1,000 days are critical for brain development,” says epidemiologist Jiazhen Zheng of the Hong Kong University of Science and Technology in Guangzhou, China. During that period, the brain undergoes exceptionally rapid growth and neuronal development, he says.

Data already suggest that high sugar intake early in life may lead to health problems, including diabetes and high blood pressure. Zheng had previously studied the effects of sugar on the cardiovascular system and wondered if it might also influence brain health.

He and his colleagues pored over health records of nearly 65,000 people in the U.K. Biobank who were in utero, infants or toddlers between July 1942 and June 1954. During those years, they would have been subject to a British government policy that set a daily limit on the amount of sugar a person could purchase. This policy, an austerity measure for World War II, allowed each person 41 grams of sugar a day — roughly the amount of sugar in a 12-ounce can of Coke today.

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

Other factors beyond sugar consumption may have also played a role, Zheng says, so he can’t say how much sugar is safe to consume to reduce risk.

Still, given, the data, what families should do is limit added sugars in their children’s diets, he says. The Dietary Guidelines for Americans, for instance, don’t recommend any added sugars under 11 years old. “That’s one of the best things they can do, a sensible step for children’s overall health,” he says.