by Probiotics have been getting a lot of attention lately. These bacteria, which you can eat from fermented foods, yogurt or even pills, are linked to a number of health and wellness benefits, including reducing gastrointestinal distress, urinary tract infections and eczema. But can they also improve your mood?
Behavior and mental health are complex. But the short answer, according to research recently published by my team, is probably yes.
The beneficial bacteria in probiotics become part of a community of other microscopic organisms that live in your digestive system called the gut microbiome. Your gut microbiome contains trillions of different bacteria, fungi and viruses.
Hundreds of species of bacteria are native to the intestinal tract. Each species can be broken down into hundreds of strains that can differ greatly in their metabolism, by-products and environmental preferences.
This bacterial diversity is why not all probiotics are created equal. Many research groups have shown that there are specific types of it Lactobacillus Effects are mood-enhancing.
But these effects seem to only occur with the right mix of bacteria in the right conditions. For example, a probiotic that may reduce stress symptoms in someone worried about their last calculi may not work in someone with symptoms of post-traumatic stress disorder.
Studying mood in mice
In my work as a neuroscientist, I study how the gut affects the brain. My team and I recently conducted experiments in mice that support the idea that gut microbiota plays a role in stress regulation.
So how do you measure the mood of mice?
First, we needed to understand how mice behave under stress. So we subjected them to short periods of stress: they are restrained for two hours each day, given enough space to move around but not enough to groom or stand up. We imagine this is the same kind of stress that people experience when they are confined to a car or cubicle for hours at a time.
Stressed mice displayed behaviors similar to depression and anxiety, which we measured by monitoring the amount of time they spent hiding when placed in a new environment or how quickly they tried to right themselves when turned upside down with them.
While it’s no surprise that stressed mice hide longer and are slower to correct themselves, their behavior had the power to change their behavior.
To determine whether stress behavior could be transferred through the microbiome, we used another group of mice that were completely clean. These mice were free of any bacteria, fungi or viruses and lived in a rubber bubble. They basically had no microbiome at all.
We exposed them to mice from stressed or normal mice by sprinkling soiled bedding into their enclosures. Microbes from the donor mice began to populate the gut microbes of the clean mice.
Within a few weeks, the clean mice exposed to poop from stressed mice began to develop stressful and anxious behavior, although nothing else changed. Meanwhile, clean mice exposed to poop from normal mice had no differences in their behavior. This finding suggests that the microbes in the gut changed the behavior of the mice.
Which bacteria affect mood?
The results of our experiment brought us back to our original question: Which bacteria can change your mood?
We started by comparing the microbes in the guts of stressed and normal mice. In our analysis, we discovered that a group of bacteria is known Lactobacillus is greatly reduced in stressed mice. Research has previously linked this group of bacteria to stress reduction. But, Lactobacillus there are over 170 different species and even more songs.
Currently, the probiotic supplements available to patients are unregulated and often untested. In order to reliably find the most effective types for patients, they must be properly tested. So we had to find a way to test how different types affect anxious behavior.
Instead of tackling this huge task alone, we created a method that other microbiome scientists can also use to look at this group of bacteria as systematically as possible.
In order to recreate the same experimental conditions for all microbe species, we created a group of mice whose microbiome contained only six species of bacteria, the bare minimum required for normal healthy development, which did not count. Lactobacillus. In this way, we could individual types of it Lactobacillus back into the gut microbiome of mice and observe the effects of each stressor on their behavior and biology.
We have tested two series so far: Lactobacillus intestinalis ASF360 and Lactobacillus murinus ASF361. Mice with these two sets of Lactobacillus more resilient against stress and have neural pathways associated with quiet fear.
What lies ahead?
Our study of how different types of Lactobacillus Affecting mood is just the beginning. We hope that our research will open up avenues for other scientists to test different probiotics.
Although researchers are reaching a consensus that the bacteria in your digestive tract can influence your mood, and vice versa, there is still a lot of testing to be done in animals and humans.
Our team is beginning to develop ways to systematically test which bacteria can provide the best health outcomes for humans and which probiotics are most effective. Meanwhile, give the Lactobacillus in your gut some love through a healthy diet, probiotics-rich.
This article is republished from The Conversation, a non-profit, independent news organization that brings you reliable facts and analysis to help you make sense of our complex world. It was written by: Andrea Merchak, University of Florida
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Andrea Merchak has received funding from the National Institutes of Health (T32 NS115657, F31 AI174782).
