Longitudinal relationship of diet and oxidative stress with depressive symptoms in patients with metabolic syndrome after following a weight loss treatment: the RESMENA project.

BACKGROUND & AIM: Metabolic syndrome and depression seem to share some common underlying mechanisms, although less is known about the impact of metabolic syndrome dietary treatments on depression. This study examined the association between a hypocaloric treatment designed to reduce metabolic syndrome features in self-perceived depression and the potential involvement of dietary components and oxidative stress changes. METHODS: Analyses were based on volunteers (n = 55) with metabolic syndrome (age 50 ± 1 y.o.; 38M/17F), where depressive symptoms were assessed using the Beck Depression Inventory. Participants followed two hypocaloric diets (control diet and RESMENA diet) with the same energy restriction (-30% TCV) for six months. Depressive symptoms, dietary records, anthropometrical measurements, biochemical parameters and oxidative stress levels were analysed. RESULTS: Both diets improved self-perceived depression similarly (p = 0.528). Participants with lower depressive symptoms at baseline reported a significantly higher intake of omega-3 polyunsaturated fatty acids (p trend = 0.002). Interestingly, after adjusting for potential confounders, the increase in folate consumption (p = 0.011) and the decrease in plasma malondialdehyde levels (p = 0.012) throughout the intervention, were associated with the improvement in depressive symptoms. CONCLUSIONS: A higher intake of folate and a decline in malondialdehyde plasma levels during a weight loss intervention, were related to improvements in manifestations of depression (www.clinicaltrials.gov; NCT01087086).