Dietary markers linked to depression, anxiety in adults with obesity

Dietary markers, such as animal protein intake, appear to contribute to depression and anxiety in individuals with comorbid obesity, reveals a study.

“Gut microbial metabolites and systemic inflammation may be biomarkers of importance within the microbiome-gut-brain-axis (MGBA),” the researchers said.

Thirty-four participants enrolled in an integrated behavioural intervention for weight loss and depression (ENGAGE-2 pilot trial) were included in post hoc analysis. Their stool and blood samples were then collected for analysis.

The research team performed Pearson partial correlation and multivariate analysis to examine the associations among changes in faecal short-chain fatty acids (SCFAs: propionic, butyric, acetic, and isovaleric acids), plasma cytokines (C-reactive protein, interleukin [IL]-1 beta, IL-1 receptor antagonist [IL-1RA], IL-6, and tumour necrosis factor-α), and 35 dietary markers over 2 months.

In addition, they also assessed changes in Depression Symptom Checklist 20-item (SCL-20) and Generalized Anxiety Disorder 7-Item (GAD-7) scores over 6 months.

Changes in the SCFAs and TNF-α at 2 months showed a positive correlation (standardized coefficients, 0.06‒0.40; 0.03‒0.34) with changes in depression and anxiety scores at 6 months, while changes in IL-1RA at 2 months displayed an inverse association (standardized coefficients, ‒0.24; ‒0.05).

Changes in 12 dietary markers, including animal protein, after 2 months correlated with changes in SCFAs, TNF-α, or IL-1RA at 2 months (standardized coefficients, ‒0.27 to 0.20). Notably, changes in 11 dietary markers, such as animal protein, at 2 months also correlated with changes in depression or anxiety symptoms scores at 6 months (standardized coefficients, ‒0.24 to 0.20; ‒0.16 to 0.15).

“These findings are exploratory and warrant replication,” the researchers said.