New Evidence: Probiotics Can Help Fight Depression

Doctors and experts have always said there’s no such thing as a cure-all when it comes to health—but new research is suggesting that probiotics might be as close as it gets to a happy pill.

Psychology Today reports on promising new trials that show probiotics aren’t just good for digestion—they can actually give your mental health a boost.

The study followed 40 patients over four weeks, and tracked their mood and likelihood to feel depressed. Twenty took a probiotic supplement containing several common strains such as lactobacillus acidophilus and bifidobacterium, and 20 took a placebo.

After four weeks, the patients who took probiotics were less likely to react negatively when put in a sad mood. Researchers consider this “cognitive reactivity” a strong indication of how vulnerable a person is for developing depression.

The connection between probiotics and mental health is likely due to something called the “brain-gut axis.” Though the study didn’t delve into exactly how probiotics can improve mood, researchers hypothesized that the microbacteria in the intestines give off feel-good chemicals that travel to the brain. Or, alternatively, researchers proposed that probiotics reduce inflammation and make the gut impermeable, keeping toxins from seeping into the rest of the body.

To pinpoint exactly how probiotics work, researchers said more human studies of these supplements were necessary.

“Even if preliminary, these results provide the first evidence that the intake of probiotics may help reduce negative thoughts associated with sad mood,” Lorenza S. Colzato, principal investigator at the Leiden Institute of Brain and Cognition, said in a statement released to Time.

To take advantage of these mood-boosting effects, try a daily probiotic supplement. Look for one with multiple strains of probiotics—the study highlighted those as the most effective.

Illustration by Katherine Prendergast