Association of time-related eating patterns with depression, anxiety and stress in apparently healthy adults living in Tehran

We aimed to determine the relationship between time-related eating patterns and depression, anxiety, and stress in adults living in Tehran. This cross-sectional study included 450 adults aged 20–59 years recruited via convenience sampling from Tehran University’s Jahad Daneshgahi center. Dietary data were collected using three non-consecutive 24-hour recalls. Outcomes were assessed with the validated Depression Anxiety Stress Scales-21 (DASS-21). Multivariable logistic regression models and restricted cubic spline dose–response analyses were used to evaluate associations. The mean ± standard deviation of age was 39.3 ± 9.51 and 37.1 ± 9.79 in men and women, respectively. Later breakfast timing (highest vs lowest tertile) was significantly associated with higher odds of depression and anxiety after adjustment. Significant non-linear U-shaped relationships were observed between breakfast time (lowest at 8:30), lunch time (lowest at 13:30), and overnight fasting duration (lowest at 10:30 hours) and the odds of depression and stress; similar non-linear patterns linked lunch timing and overnight fasting with anxiety. A non-linear association was found between dinner time (lowest at 20:30) and stress. Later breakfast consumption was associated with higher odds of depression and stress. Non-linear relationships between several meal-timing variables and mental-health outcomes suggest that both very early and very late eating may be linked to poorer mental health.