Association between thiamine intake and depression: A national cross-sectional study

Area of Science:

• Nutritional Psychiatry
• Epidemiology
• Public Health

Background:

• Growing interest in dietary interventions for depressive symptoms.
• Unclear association between thiamine (vitamin B1) intake and depression.
• Need for research using large-scale population data.

Purpose of the Study:

• To investigate the association between thiamine intake and depression in American adults.
• To explore potential nonlinear relationships and identify inflection points.
• To examine subgroup differences based on age and sex.

Main Methods:

• Cross-sectional study utilizing data from American adults.
• Logistic regression and multivariable models to assess associations.
• Restricted cubic splines and recursive algorithms to identify nonlinear trends and inflection points.
• Stratified analyses by age and sex to evaluate subgroup effects.

Main Results:

• A statistically significant nonlinear association was observed between thiamine intake and depression.
• An inflection point at 1.35 mg/day was identified; intake below this level showed a protective effect (OR: 0.68, 95% CI: 0.53–0.89).
• No significant association was found for thiamine intake above the inflection point (OR: 1.10, 95% CI: 0.92–1.31).
• The nonlinear association was consistent in women and individuals younger than 60 years.

Conclusions:

• Thiamine intake exhibits a nonlinear relationship with depression in American adults.
• Optimal thiamine intake may be crucial for mitigating depression risk, especially in specific demographic groups.
• Further research is warranted to confirm these findings and explore underlying mechanisms.