Can Probiotics Treat Depression?

Probiotics and depressionThe importance of the gut for overall health is now being increasingly recognised. The gut has several important roles in the body including the digestion of food, and the absorption and production of many nutrients. The gut also has a major influence on our immune system and is involved in the production of many hormones. Our digestive tract contains trillions of bacteria which help with the function of the gut. When bacteria levels (known as gut flora or probiotics) are out of balance it can have detrimental effects on our health. In fact, several studies have now confirmed that probiotic supplementation is beneficial for overall health and can help treat many diseases (not just related to the gut).

The role of the gut and probiotics for mental health has attracted increasing interest over the last decade although there has been little research investigating the effects of probiotic supplementation for the treatment of mental health conditions such as depression and anxiety.
Researchers have just published a study in the journal, Nutrition, investigating the effects of probiotic supplementation in people with depression [1].

In this randomised, double-blind, placebo-controlled study, forty adults with depression were randomly allocated into one of two groups; probiotic supplementation or placebo for 8 weeks. The probiotic capsule contained three strains of bacteria: Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium bifidum.

After 8 weeks of intervention, people who received the probiotic supplements experienced significantly greater improvements in mood compared to those on the placebo. In addition, people taking probiotics experienced the following:

  • Greater decreases in serum insulin, which indicates improvements in insulin resistance
  • Greater reductions in c-reactive protein (CRP) levels, which points to reduced inflammation
  • Greater increases in glutathione, which indicates improvements in antioxidant defences

This study provides initial support for the benefits of probiotics for people with depression and highlights the crucial relationship between the gut and the brain. If you want to improve mental wellbeing, then you must not neglect the health of your gut. This includes looking at the foods you eat, the medications you take, the toxins you are consuming, and your overall stress levels.


1. Akkasheh G, et al. Clinical and metabolic response to probiotic administration in patients with major depressive disorder: A randomized, double-blind, placebo-controlled trial. Nutrition. 2015 Sep 28. pii: S0899-9007(15)00391-3. Pubmed link