Suicide & diet: New study links poor nutrition & depression

Diet linked to emotional state / Image generated by a neural network, photo editor: Dastan Shanay

A study in Kazakhstan links the gut microbiome to emotional health and suicide risk.

According to Alibek Kossumov, a senior researcher at the National Laboratory Astana (NLA), diet may influence not only physical health but also brain function — and in some cases, even the likelihood of suicidal thoughts.

Inaugural study

The research, the first of its kind in Kazakhstan, analyzed gut microbiome samples from people who had died by suicide. It involved 71 individuals aged 30 to 42, including a healthy control group.

Kossumov explained that the team set out to clarify whether and how gut bacteria may affect emotional and mental health, which could relate to suicide risk.

Lab tests / Photo: Kursiv.media

Pathological pathways

The study found that individuals who died by suicide had gut bacteria linked to pathological metabolic pathways, i.e., chemical reactions within a cell, involving inflammation, infection and antibiotic resistance, especially to beta-lactams. Higher activity in the pentose phosphate pathway, related to the body’s stress response, was also identified.

In comparison, the control group showed gut bacteria associated with pathways that support nervous system stability and serotonin production — processes tied to emotional resilience.

Alcohol and drugs

Adding context to these biological findings, among those who had died by suicide, 16 had alcohol in their blood, three had drugs, and 22 had unhealthy lifestyle habits, including smoking.

Kossumov highlighted that the study suggests diet shapes the gut microbiome, influencing emotional well-being and potentially acting as a risk factor for suicide, although not a direct cause.

Notably, about one in 10 men and one in four women experience depression during their lifetime, and 11% to 17% of suicide cases are associated with depressive disorders. Overall, 60% to 70% of those who die by suicide have suffered from severe depression.