Stress Test: Learn How these Probiotics Can Fix Your Anxious Gut

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Stress Test is a series about the science behind our busy lives and how stress affects our bodies. The biweekly column uncovers the latest research and explains how to put it to use in a practical way. Look for the science behind epigenetic markers of stress, mindfulness, meditation and deep brain stimulation.

As scientists study the mind-gut connection, as they call it, they’re beginning to suggest that healthy bacteria can fix a variety of issues, including stress and weight gain. Now marketed as probiotics and prebiotics, these healthy bacteria live in our intestines and promote proper digestion. The opposite of antibiotics, which are prescribed for some illnesses to eliminate “bad” infectious bacteria, these guys build up your immunity and prevent conditions such as irritable bowel syndrome, diarrhea and urinary tract infections.

Although probiotics started gaining notice in popular culture in the 1990s and 2000s (recall those Jamie Lee Curtis ads about being “regular” with Activia yogurt), they’ve popped back on the scene again as researchers have found benefits for skin conditions such as eczema, dental health and prevention against allergies and colds. In the latest rounds of studies, a few researchers have posed the idea of probiotics as the new era of biotherapy.

Other scientists are looking at ways to use probiotics to treat diabetes, post-traumatic stress disorder and stressed-related diseases that cause autoimmune problems. Initial studies are being conducted in chickens, rats and fish to test the stress-probiotic connection, too.

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The popularity boost comes from new products on the market as well. First promoted in dairy foods such as yogurt and fermented foods such as kimchi, probiotics are now being sold through the new surge of interest in kefir, kombucha and tempeh, as well as sold alone. Before shopping for your next gut product, however, keep these facts in mind as you seek to tame your stress-related tummy rumbles.

1. Our bodies depend on the organisms that live within us.

It seems weird to consider, but as living organisms, we’re also made of other living organisms that keep us going. These bacteria gobble up the food particles that we put in our bodies and make the building blocks we need to live, such as neurons, proteins and other molecules. Have you heard about the fecal transplants that have helped people cure colon diseases or lose weight by injecting healthy bacteria (read: poop) in their gut? It’s strange, but it’s true, and scientists are finding more links to diabetes, obesity and neurodegenerative disease. It seems the microbiota in our bodies do more to regulate insulin, metabolize fat, reduce inflammation and prevent Alzheimer’s and Parkinson’s than we ever thought. Essentially, it’s important what we put in our mouths.

2. Scientists are still learning why this is true.

As with any research, questions remain. Although scientists have observed these mind-gut connections in recent years — and majorly improved how procedures such as fecal transplants help patients — they’re still not quite sure how probiotics reduce damage and stress on the body. This antioxidant property, as they call it, prevents the generation of free radicals, which are particles that kill cells and break down the body’s functions. Studies released in the past few months have surmised how DNA molecules are harmed and how gut bacteria fight against it, but they’re still looking for the exact time and place that it happens in cell development.

3. Either way, nutrition matters.

Have you noticed when you eat fast food that you feel sluggish, bloated and foggy? That’s your gut bacteria talking. They’ll use up whatever food particles you give them, but they may do it slower and less effectively. Likewise, if you crave salty, fatty and sugary foods, they’re talking again. Those are the “bad” gut bacteria searching for the junk foods that bring you comfort when stressed. Healthy fruits, veggies, grains and proteins promote the healthy bacteria and knock out that high-low drop that happens when you eat food that doesn’t sustain your body’s functions, according to researchers at Washington University in St. Louis.

4. Studies show mixed results about psychological stress.

Probiotics help a stressed body, but the impact on anxiety and depression is still up in the air. In one study released in May, Baylor University professors didn’t observe any difference in psychological stress for 105 participants who took probiotic supplements for two weeks. In another study released in April, though, researchers in Japan saw probiotic milk help 50 fourth-year medical students sleep better during intense exams. Systematic reviews that looked at several probiotic-related studies have seen “some promise,” but they say, “work in this area is nascent.”

5. So far, the FDA regulates probiotics like foods, not medications.

Probiotic supplement companies don’t have to prove their products work or that they’re necessarily safe. Although the products are generally safe and beneficial, some brands can cause the side effects you’re trying to prevent, such as diarrhea, gas and bloating. (And some have been recalled!)

Look for the top brand names and make sure the ingredients don’t conflict with any current medications you take. A heavy dose of the Lactobacillus bacteria found in some yogurts, for example, can fight against immunosuppressants such as cyclosporine, prednisone and corticosteroids used for autoimmune diseases. This may seem like common sense (or even counterintuitive), but taking antibiotics at the same time as taking probiotics can actually stress your body even more. Talk to a doctor about the best way to coordinate your medications and supplements to build those healthy bacteria back up.

Image: Ryan Snyder via Flickr, CC-BY

Carolyn Crist is a freelance health and science journalist for regional and national publications. She writes the Escape Artist column for Paste Travel, On the Mind column for Paste Science and Stress Test column for Paste Health.