When you learned about the human body in school, you were probably told that the brain controls everything in the body. What we now know, is that the gut can also control the brain, influencing your mood and behaviour.
This influence of the gut on the brain isn’t actually new – we’ve known for a long time that the gut influences the brain to control eating behaviour, like making you hungry or feel full. It’s not the gut itself that influences the brain, but the colony of bacteria and other organisms which live in the gut, called the microbiota or gut flora.
Everyone has a mixture of different types, or strains, of bacteria in their guts. If the good outnumber the bad, you have a normal, healthy gut flora; if the bad outnumber the good we call it dysbiosis, and this has the potential to cause health problems.
Preliminary research is now showing that along with influencing behaviour to do with eating, the gut can also influence things like stress, low mood and mild anxiety.1-3 In particular, two strains of bacteria, named Lactobacillus helveticus R0052 and Bifidobacterium longum, have shown promise in reducing stress symptoms,4,5 as well as reducing stress-related stomach problems like diarrhoea and pain.6 These studies suggest just how important the gut microbiota is for our moods.
While this might sound a bit confusing, rest assured that there are some very simple things you can do to counteract the influence of your gut flora. The priority is to begin changing your gut flora from one which is majority bad bacteria, to one which is majority good. This can be done via probiotics, especially the strains already mentioned above, while supporting your existing good bacteria with prebiotics. Prebiotics are types of fibre which we can’t digest, but they help the good bacteria flourish! You can get special supplements which contain prebiotics, but eating a diet rich in fibrous vegetables, like broccoli, cabbage and kale, is also advisable. On the subject of diet, it’s best to avoid sugar and fatty fried foods, which encourage the bad bacteria to grow.
If you’re suffering from low mood or mild anxiety, you may want to consider some additional herbs and nutrients, which can get to work while you give your microbiota a helping hand with probiotics:
- St. John’s Wort
- S-adenosylmethionine (SAMe)
- Omega-3 fatty acids, especially DHA
- B vitamins
Whenever you take herbal supplements, it’s important to check with your healthcare professional that these are appropriate for you, and that they won’t interact with any medication you may already be taking.
Make sure to always read the label and use only as directed. If symptoms persist, see your healthcare practitioner.
To find a practitioner in your area, visit our find-a-practitioner page.
- Cryan JF. Stress and the microbiota-gut-brain axis: an evolving concept in psychiatry. Can J Psychiatry 2016;61(4):201-203.
- Evrensel A, Ceylan ME. The gut-brain axis: the missing link in depression. Clin Psychopharmacol Neurosci 2015;13(3):239-244.
- Mayer EA, Tillisch K, Gupta A. Gut/brain axis and the microbiota. J Clin Invest 2015;125(3):926-938.
- Messaoudi M, Lalonde R, Violle N, et al. Assessment of psychotropic-like properties of a probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) in rats and human subjects. Br J Nutr 2011;105:755-764.
- Akkasheh G, Kashani-Poor Z, Tajabadi-Ebrahimi M, et al. Clinical and metabolic response to probiotic administration in patients with major depressive disorder: a randomized, double-blind, placebo-controlled trial. Nutr 2016;32(3):315-320.
- Diop L, Guillou S, Durand H. Probiotic food supplement reduces stress-induced gastrointestinal symptoms in volunteers: a double-blind, placebo-controlled, randomized trial. Nutr Res 2008;28:1-5.