Scientists at the University of Oxford have shown that taking a probiotic to balance the gut's 'good bacteria' has a direct impact on mood and depression levels. Intrigued? Why wouldn't you be...

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You’ve heard the saying “butterflies in the stomach” or “gut instinct”, but have you ever considered what they suggest in terms of how we process emotion? That distinctive fluttering sensation we get when we’re feeling overwhelmed proves that our gut has a direct link to the brain, and makes up part of our physiological stress response. If you flip-reverse that biological chain of events, it’s only logical that a healthy gut can help to improve brain function (i.e. mood).

The more scientists learn about our gut microbiome (the 100 trillion bacteria that take up residency in our gastrointestinal tract), the more they realise the importance of nurturing this complex community of microflora. How? By taking probiotics - the “good bacteria” responsible for optimising gut and immune function, and therefore impacting our overall health and mood.

There are a number of factors that can disrupt this crucial balance of bacteria, including stress, antibiotics, illness, and poor nutrition. Taking a live bacteria to supplement those microflora can help to restore the balance, as shown in a recent study by scientists at the University of O xford.  The probiotic they used was by Bio-Kult  (a range of probiotic dietary supplements), and more specifically, their  advanced multi-strain formulation containing 14 live bacterial cultures , which are proven to survive the high acidity of the stomach.

The study findings

It was shown that taking a probiotic for just four weeks improved mood, emotional processing, and even the ability to read faces. It was a randomized, double-blind, placebo-controlled (read: gold-standard) study, using a total of 71 participants aged 18-55, all considered to be suffering with mild to moderate depression.

At the end of the four-week trial, participants were asked to perform a series of tasks to measure their emotional processing and cognitive function (compared to those given a placebo). The results showed a 12% increase in accuracy at identifying and classifying facial expressions, improved concentration, and heightened perceptiveness.

But the key finding was that participants taking the “gut friendly” bacteria recorded a near 50% reduction in depression scores, adding to a growing body of evidence that suggests our gut microbiome can have a significant impact on our mood.

“Our findings suggest that probiotics could be used as an early intervention to help reduce the risk of people with mild to moderate depression developing a major depressive disorder, which is more debilitating and often difficult to treat,” says associate professor from the Department of Psychiatry at Oxford University, Phil Burnet.

Victoria Collard, a research psychologist and associate lecturer at the Open University added: “We know that there is a lot of truth in the adage that a healthy body leads to a healthy mind. These findings are really interesting in terms of shedding light on the role that probiotics might play in protecting our mental health.”

The science behind the study

Researchers attached to the trials have offered up a number of possible explanations for how probiotics impact mood, one being that they are able to influence one of the brain’s main signalling molecules and restore levels of serotonin (our happy hormone). Dopamine is another chemical messenger we produce associated with mood and motivation, and clinical psychologist Dr Rita Baião who led the research team said that she “couldn’t rule out” the impact of probiotics on central dopamine, which is also influenced by gut microbiota.

“The changes in emotional processing associated with probiotics are quite different from those seen with antidepressants,” adds Dr Baião. “Probiotic administration may be an ‘early intervention’ strategy to reduce the risk of people with mild to moderate depression developing major depressive disorder.”

The fact that our mood might be affected by a community of bacteria thriving in our gastrointestinal tract is rather a lot to take on board, but with so much evidence pointing towards our gut being our “second brain”, supplementing it with the live microorganisms it requires to support other vital bodily functions seems like a small self-care upgrade to make, wouldn't you agree?

Why Bio-Kult?

Bio-Kult is a unique multi-strain live bacteria supplement formulated with 14 strains of live bacteria that target the digestive tract and rebalance the gut microflora. It should be taken as part of a healthy balanced diet (swallowed whole or pulled apart and mixed with food or drink), and is suitable for people who are pregnant, vegetarian, on antibiotics, and children three years+. It doesn't need to be refrigerated, making it great for people who travel, and the best part? It's backed by science...

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The results discussed in the above research were published in 2022 in Baião R, Capitão LP, Higgins C, Browning M, Harmer CJ, Burnet PWJ. Multispecies probiotic administration reduces emotional salience and improves mood in subjects with moderate depression: a randomised, double-blind, placebo-controlled study. Psychol Med. 2022 Feb 7:1–11