The joint associations of physical activity and ultra-processed food consumption with depression: A cohort study in the UK Biobank.

BACKGROUND

Despite substantial evidence regarding independent associations between physical activity (PA) and ultra-processed foods (UPF) consumption with depression, the joint effects of these two factors remain unknown.

METHODS

This study included 99,126 participants without depression in the UK Biobank at baseline. A 24-h recall method was used to assess UPF consumption, and self-reported total physical activity (TPA), moderate-to-vigorous physical activity (MVPA), and vigorous physical activity (VPA) were assessed by metabolic equivalent task (MET). A series of Cox proportional hazard regression models were used to explore the independent and joint effects of TPA, MVPA, VPA and UPF consumption on depression.

RESULTS

The incidence rate of depression was 1.94 % [95 % confidence interval (CI): 1.80 %-2.10 %] per 1000 person-years after an average follow-up of 12.10 years. We found that MVPA and UPF consumption had additive interactions on depression risk (p < 0.05). Participants in Q1 of TPA and Q4 of UPF consumption (HR: 1.83, 95%CI: 1.45-2.31) showed a higher risk for depression than those in Q4 of TPA and Q1 of UPF consumption. Compared with the participants with WHO guideline-recommended MVPA and the lowest UPF consumption, those below recommended MVPA (HR: 1.51, 95%CI: 1.20-1.89) or above recommended MVPA (HR: 1.40, 95%CI: 1.10-1.78) and with the highest UPF consumption had a higher risk for depression.

LIMITATIONS

Study limitations include use of self-reported data, observational study and concerns regarding generalizability.

CONCLUSION

Higher UPF consumption, accompanied by lower PA levels regardless of TPA, MVPA, and VPA, is associated with a higher risk of depression. Our study offers insights on public health priorities to decrease the risk of depression in the population by addressing both PA and UPF consumption together.