Early life sugar restriction linked to lower anxiety and depression risk decades later

Diet in the earliest stages of life may have lasting implications for mental health. A study published in General Psychiatry reports that exposure to sugar rationing during the first 1000 days after conception was associated with lower risks of anxiety and depression later in life. The findings draw on a historical change in British food policy, offering an unusual opportunity to examine how early dietary environments may relate to mental health decades later.

The researchers used the end of sugar rationing in the United Kingdom in September 1953 as a natural experiment. Sugar consumption rose sharply after rationing ended, while the availability of other foods remained relatively stable. They analyzed data from 66,223 UK Biobank participants born around this transition and compared people with different durations of exposure to rationing, ranging from exposure only before birth to exposure extending to about age two. Exposure was estimated from birth dates relative to the policy change, rather than measured from individual food records.

Across the study population, exposure to rationing was associated with a 17% lower risk of anxiety and a 14% lower risk of depression compared with no exposure. The strongest associations appeared among people exposed from conception through age two: who had approximately 24% and 21% lower relative risks of anxiety and depression, respectively. The association generally strengthened as the duration of early life exposure increased.

The study also examined when an anxiety or depression diagnosis was first recorded. Among those exposed to rationing throughout the first 1000 days, the first recorded anxiety diagnosis occurred about two years later, and the first depression diagnosis about four years later, than among those without early exposure.

The authors discuss several possible biological explanations, including the ways early nutrition could influence stress regulation, inflammation and brain development. These mechanisms were proposed from prior research and were not directly tested in the UK Biobank analysis. The findings support further investigation of how dietary conditions during pregnancy and infancy may shape mental health across the life course.

The results should be interpreted in light of the study design. Researchers inferred sugar exposure from the historical rationing policy and did not measure each participant’s sugar intake in childhood. Unmeasured factors, such as other aspects of maternal diet, may also have influenced the results.

By linking a historical policy change to health records later in life, the study adds evidence that early dietary environments may be associated with the risk and timing of common mental health conditions. Further work measuring individual diets and examining other populations will help clarify the relationship and its implications for public health.