Updated: Dec 8, 2021
Let’s unpack some of the exciting new research about the link between gut health, mood, and stress. More specifically, lets discuss your friendly resident gut microbes, probiotic foods, and supplements. I will also offer some simple recipes to keep your gut and taste buds happy.
There are trillions of microbes that happily live in our gut. These friendly microbes do more than help us digest foods, make vitamins, and protect us from the not-so-friendly microbes - they have mood-boosting and stress-busting functions too.
It’s a hotbed of research right now and we’re finding out more about their awesome health and mood/stress benefits every day. And, while the research is just starting to figure out the many gut microbe-brain connections, it’s such a cool new topic that I couldn’t wait to share it with you!
GUT MICROBES AND PROBIOTICS
The microbes that live in our guts are known as our “gut microbiota”. The microbes that we can ingest are known as “probiotics”.
“Probiotics” are live organisms that you can eat, drink, or take as a supplement. They turn milk into yogurt, and cabbage into sauerkraut; and they are great for both your gut health and mental health. Special probiotics that have mental health benefits are called “psychobiotics,” (psycho = mental health, and biotics = live). They are live organisms that can benefit our psyche.
PROBIOTIC-RICH FOODS AND SUPPLEMENTS
Probiotics can be found in yogurt, sauerkraut (and other fermented veggies), miso, tempeh, and kimchi. You can drink them in kefir or kombucha.
Of course, there are a number of probiotic supplements available too. Check with your healthcare provider to identify which one is best for you. Generally, I look for ones that have at least 10 strains and at least 10 billion active cultures. It is a good idea to look for one that has been “third party tested,” which means someone outside the company has tested it and says it’s a quality product.
Also, be sure to read the label before taking any supplements. The probiotics with the most research are of the Bifidobacterium and Lactobacillus types.
SIMPLE, PROBIOTIC-RICH RECIPES
It may not seem obvious or intuitive, but your body is interconnected in many ways and more research is focusing on the “microbiota-gut-brain axis.” It’s the very complex connection between your gut, its microbes, and your brain. This new field has been called a “paradigm shift in neuroscience” (Dinan, 2017).
In fact, there are a number of ways that we’re beginning to understand how our gut microbes can affect our brain. One is via the “vagus” nerve, which is a nerve that directly connects your gut to your brain. The other ways are through “biochemical messengers.” Biochemicals that are made in your gut and travel throughout the body to communicate with other organs, including your brain. Examples of biochemicals include short chain fatty acids, cytokines, and even tryptophan.
The exciting thing is that this may help us with not only mood and stress, but the microbiota-gut-brain axis may one day prove to be helpful for other health conditions.
MOOD, STRESS, AND YOUR MICROBES
Several studies show that stressed rodents not only have increased stress hormones and stressed behaviors; but, they also have different gut microbes! This has also been studied, to a small extent, in people too. But, can it work the other way around? Can changing our gut microbes affect our moods and stress responses?
Studies of rodents that grow up without any gut microbes at all (in a “bacteria-free” environment) respond to stress more than mice with normal gut microbes. Then, when they’re given either a probiotic or gut microbes from non-stressed mice, their stress responses often go back to normal.
“Gut microbiota and probiotics alter behavior and brain neurochemistry.” (Ait-Belgnaoui, et. al., 2012) That’s a pretty powerful statement.
Many animal studies show positive effects on behavior when they get probiotic supplements. Human studies show that after a few weeks of taking probiotic foods or supplements, healthy people have reduced stress hormones, feelings of stress, negative thoughts, and sad moods.
One fascinating study showed that when people took probiotics, brain MRI (magnetic resonance imaging) tests showed reduced brain activity for negative and aggressive thoughts!
There is some exciting research on the positive effect that probiotics can have on moods and stress. So, what can you do to nurture your own healthy gut microbes?.
In Part 1 we talked about the benefits of consuming probiotic-rich food. Once the gut microbes take up residence in our guts, we need to feed them!
PREbiotics are food for gut microbes and, when fermented in the gut, produce specific changes in bacterial composition or activity. They are your friendly gut microbes’ favorite meal which helps them to grow, and multiply. Prebiotics are basically foods that contain fiber. Things like fruits, vegetables, nuts, and seeds. Even dark chocolate. Foods that are particularly high in prebiotics include jicama, asparagus, avocado, whole grains, and allium vegetables like onions, garlic, leeks, and shallots.
Giving animals prebiotics has shown to reduce stress hormones, and anxiety-related behaviors. In people, studies show that taking psychobiotics along with prebiotics can improve both the microbes in our gut, as well as our mood.
Check out Nutrition Advantage for more meal planning resources.
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