Dietary sugar exposure in early life and risk of adult mental health disorders: UK Biobank cohort study

ABSTRACT Recent findings suggest that sugar rationing during the first 1000 days of life may influence chronic disease risk in adulthood. Given the link between mental health and non-communicable diseases, early-life sugar restriction may be associated with later-life incidence of anxiety and depression. Using UK Biobank data, participants born between October 1, 1951, and March 31, 1956 (n = 46,448) were grouped by duration of exposure to sugar rationing: R270 (rationed from conception to 270 days of life, n = 9,671), R425 (n = 6,984), R635 (n = 6,622), R817 (n = 7,096), R1000 (n = 6,856), and never-rationed groups NR0 (conceived immediately after sugar rationing ended, n = 6,117) and NR455 (conceived after all food rationing ended, n = 3,102). The liking of sweet foods was assessed via food preference questionnaires, and anxiety/depression diagnoses via linked ICD-10 health records. Survival analyses were conducted using Weibull accelerated failure time models, adjusted for demographic, lifestyle, and health covariates. Structural equation modelling (SEM) was used to assess outcomes and causal pathways. The R1000 group reported lower sweets preference (mean score = 5.82 vs. 6.04 in NR455, p = 0.0042) and showed significantly reduced hazards of anxiety (HR = 0.67, 95% CI: 0.53–0.84) and reduced hazards of depression (HR = 0.71, 95% CI: 0.57–0.87). Protective associations for anxiety remained robust across sensitivity analyses, including adjustment for later-life sugar intake, whereas associations for depression were attenuated and non-significant. SEM confirmed a direct effect of sugar rationing duration on anxiety (γ = – 0.144, p = 0.012), but not depression. Exposure to sugar rationing during the first 1000 days of life was associated with reduced risk of anxiety in adulthood, independent of later dietary behaviour. These findings highlight the importance of early developmental environments in shaping psychiatric outcomes and suggest that nutritional exposures may confer resilience against anxiety disorders. Effects on depression were weaker and appear partly explained by later-life factors.