Reducing sugar intake during the earliest stages of life is associated with a lower risk of dementia, a later onset of the disease and better indicators of brain health in later years, a new study has found.
"Limiting sugar during the earliest stages of life may have lasting benefits for brain health," said Jiazhen Zheng of the Hong Kong University of Science and Technology in Guangzhou, one of the study's authors.
"These results highlight the potential importance of early-life nutrition in reducing the risk of dementia decades later," Zheng added.
Researchers analysed data from nearly 65,000 people born before and after the Second World War, taking advantage of a natural experiment created by the British government's sugar-rationing programme.
Sugar rationing was introduced during and after the war and remained in place until 1953. Once restrictions ended, average daily sugar consumption in the UK almost doubled, increasing from around 41 grams to 80 grams.
The researchers divided participants into groups based on their exposure to sugar rationing:
- Those exposed before birth and during their first year of life.
- Those exposed before birth and up to the age of two.
- Those born after rationing ended.
Using medical records from when participants were around 55 years old, the researchers tracked dementia diagnoses over the following 15 years.
The study found that people exposed to sugar rationing before birth and during their first year of life had a 21% lower risk of dementia than those born after sugar rationing ended.
For those exposed before birth and up to the age of two, the risk was 23% lower.
Among participants who eventually developed dementia, those exposed to lower sugar levels early in life were diagnosed, on average, 2.6 years later than those who were not.
Researchers wrote that:
"Sugar restriction in the first 1,000 days was associated with lower dementia hazards, delayed onset, and more favorable brain-health profiles."
They added that the findings support reducing sugar intake early in life as a potential strategy for lowering dementia risk.
Zheng said that limiting added sugars during pregnancy and infancy could be one practical step families and communities can take, while stressing that further research is needed to better understand how early-life sugar exposure influences dementia risk.
