There are more microbes inside our gut, than all of the human cells that make us. That’s right, we’re more than half microbe! So, how can they NOT impact our health?
Let’s unpack some of the exciting (and preliminary) new research about the link between gut health, mood, and stress. We’ll talk about your friendly resident gut microbes, probiotic foods, and supplements, as well as 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 hot topic 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 we 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. Be sure to choose unpasteurized ones that will be refrigerated in your local grocer. Unpasteurized foods are not recommended if you are pregnant or have a compromised immune system, so please check with your healthcare provider.
Of course, there are several probiotic supplements available too. Check with your healthcare provider to identify which one is best for you. Generally, we look for one that’s refrigerated and has at least 10 billion active cultures. We also suggest you 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. But we still don’t know enough about the psychobiotic effects to make specific mood-boosting recommendations yet.
SIMPLE, PROBIOTIC-RICH RECIPES
Confetti Vegetable Salad with Miso Dressing
Cauliflower Olive Salad with Yogurt
Strawberry Almond Chia Pudding
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 amino acid that the neurotransmitters melatonin and serotonin are made from).
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 conditions like autism and Parkinson’s.
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. One study showed that moms with high levels of stress hormones during pregnancy had infants with more of the “bad” gut microbes.
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 powerful statement.
Many animal studies show positive effects on behavior when they get probiotic supplements. For example, after a probiotic, stressed rats had lower levels of both stress hormones and an inflammatory molecule associated with depression (“LPS” – lipopolysaccharide). 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 delicacies, so they’ll happily grow and multiply. Prebiotics are basically foods that contain fiber. Things like fruits, vegetables, nuts, and seeds. Even dark chocolate (preferably with at least 70% cocoa). 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.
Asparagus with Lemon Thyme Dressing
Triple Greens Soup with Avocado
Creamy Mediterranean Garlic Chicken
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