Lower Sugar During the First 1,000 Days Tied to Lower Adult Anxiety Risk and Lasting Brain Differences

New research using post‑World War II sugar rationing in Britain as a natural experiment reports that lower exposure to dietary sugar during pregnancy and the first two years of life was associated with a reduced risk of anxiety decades later and measurable differences in brain structure.

The study, published in Translational Psychiatry, analyzed health and imaging data from more than 45,000 U.K. Biobank participants born between 1951 and 1956. Researchers grouped participants by whether they experienced sugar rationing while in utero and for up to 6, 12, 18 or 24 months after birth, or only during pregnancy. The analysis also included a contemporaneous control cohort born after rationing ended and a separate cohort born in Ireland.

Overall, the lowest risk of diagnosed anxiety in adulthood was observed among people with the least early‑life sugar exposure, with the association most pronounced in women. An observed link between early sugar exposure and depression weakened after statistical adjustments for other factors.

Brain Imaging Findings: MRI comparisons of gray matter volume across 139 regions revealed significant variation across rationing groups in 80 regions. When comparing the most extensively rationed participants with those who never experienced rationing, 11 regions showed particularly strong differences, including areas in the cerebellum.

Dietary Preferences: Participants whose mothers and infants experienced the longest period without sugar—from pregnancy through 24 months—reported a lower preference for sweet foods in adulthood. More broadly, the study found differences in sweet‑food preferences between rationed and never‑rationed groups, consistent with the idea that early exposure may help set lifelong taste patterns.

“This study is compelling because it examines a real historical event,” said Dr. Ritu Goel, a child, adolescent and adult psychiatrist. She noted that rationing created a natural experiment that could not be ethically designed today, while cautioning that rationing affected more than sugar and that social and economic conditions varied for people born only a few years apart.

The lead author, Dr. Hana Navratilova (IPB University), said the team was motivated by earlier findings linking early sugar exposure with chronic physical illnesses and a preference for sugary foods that has been associated with mental‑health issues. The authors emphasize that the results show association, not causation; rationing altered overall diet and living conditions, and residual confounding is possible.

Limitations: The study is observational and relies on a historical policy as a proxy for sugar exposure. Although large and population‑based, results may reflect other dietary or socioeconomic changes tied to rationing. The authors adjusted for several confounders, but unmeasured factors could still influence outcomes.

Practical Takeaway: Clinicians cited by the study suggest the findings reinforce the importance of nutrition during the first 1,000 days of life. Rather than assigning blame, the practical message for parents and caregivers is to limit added sugars during pregnancy and early childhood as part of a balanced diet.

Citation: Navratilova, H. F., et al. (2026). Dietary sugar exposure in early life and risk of adult mental health disorders: UK Biobank cohort study. Translational Psychiatry. https://doi.org/10.1038/s41398-026-04376-w.