Soft drink consumption and depression mediated by the gut microbiome
A new cohort study suggests that regular soft drink consumption may increase the risk of depression, partly through alterations in gut microbiota composition.
Introduction
Soft drinks have long been associated with adverse health effects, particularly in the context of metabolic and cardiovascular diseases. Increasing evidence now suggests that their impact may also extend to mental health. A recent study published in JAMA Psychiatry examines the relationship between soft drink consumption and depression, highlighting the potential role of the gut microbiome in this association.
Key findings
An analysis of a large clinical cohort demonstrated a significant association between soft drink consumption and both the diagnosis and severity of major depressive disorder, with a particular focus on microbiome-related mechanisms.
Higher risk of depression
More frequent soft drink consumption was significantly associated with both the diagnosis of major depressive disorder and greater severity of depressive symptoms.
Stronger effect in women
The association between soft drink consumption and depression was notably stronger in women than in men.
Role of Eggerthella bacteria
In women, higher soft drink consumption was linked to increased abundance of Eggerthella bacteria in the gut microbiome.
Microbiome-mediated pathway
Mediation analyses confirmed that Eggerthella partially mediated the relationship between soft drink consumption and depression.
Warnings
Several important limitations should be considered when interpreting the findings:
- The cross-sectional design prevents definitive conclusions about causality.
- Soft drink consumption was self-reported by participants.
- Microbiome-related effects were particularly evident in women.
Quick facts
Sample size
The study included 932 participants, comprising 405 patients with clinically diagnosed depression and 527 healthy controls.
Explained effect
Changes in Eggerthella abundance accounted for approximately 4–5% of the association between soft drink consumption and depression.
Study design
A multicenter cohort study conducted in Germany between 2014 and 2018.
Final thoughts
Importance of prevention
Reducing soft drink consumption may represent a simple yet potentially meaningful strategy in the prevention of depressive disorders.
New therapeutic directions
The findings support the concept of targeting the gut microbiome as a complementary approach in depression treatment.
Diet and mental health
Growing evidence suggests that everyday dietary choices can influence not only physical health but also brain function and mental well-being.