By now, you’ve likely heard a lot about gut health. Or maybe your “microbiome” or “gut flora” or the importance of probiotics. But they’re not just empty buzzwords - it’s now understood that the balance of microorganisms that live in our digestive tract is absolutely vital for everything from physical and mental health to overall immunity and more. This isn’t really about being regular in the bathroom. It’s about looking and feeling your best while maintaining optimal health. We dug into the latest research and spoke with a few experts to find out what you need to know and what you need to do.
According to recent studies by the National Institutes of Health’s Human Microbiome Project, your gut’s microbiome influences the health of your entire body. Much like the way bacteria convert milk into yogurt or cabbage into sauerkraut, the good bacteria in our intestines break down dietary fiber by fermenting it. This satisfies their needs and leaves behind a helpful byproduct - organic acids that nourish and repair the cells of our body.
So what exactly is a microbiome? According to the University of Washington’s Center for Ecogenetics and Environmental Health, your microbiome is the genetic material of all the microbes and microorganisms - bacteria, fungi, protozoa and viruses - that live on and inside the human body. Not generally recognized to exist until the late 1990s, it is essential for human development, immunity and nutrition. The microbiome makes up one or two percent of your overall body weight, meaning a 180-pound man is carrying about 2 pounds of bacteria around with him everyday.
Your personal army of microbes is a hardy but sensitive bunch. They react not just to what you eat and drink, but to the amount of sleep you get, the medications you take, how often you travel or get stressed at work - all of which can foster an environment that allows more of the bad bacteria to take over for a while.
The Gut-Brain Connection
Those gut feelings you have are more real than you might know. Several studies have shown that your brain affects your gut health and your gut affects your mental health. The “gut-brain axis” is a term for the communication network that connects the two. In fact, your gut contains 500 million neurons, which are connected to your brain through nerves in the nervous system. These tiny microbes play a big role in your immune system and inflammation as well, by controlling what is passed into the body and what is excreted as waste.
Which is why you might just feel really rundown and tired when your microbiome is out of whack. Because this system is responsible for much of the production of mood-enhancing chemicals (think dopamine and serotonin) - if your bacteria balance is off, your mood is likely to feel off as well. And when your immune system is taxed, fighting the imbalance of the flora within your gut, you can feel like you’re coming down with a cold or flu.
Shelby Keys, RD, a dietitian at Boston’s Brigham and Women's Hospital explains it like this: One of the gut’s primary roles is promoting health by generating immune responses, but a dysfunctional intestinal barrier could lead to inflammation that manifests in your external barrier. For example, your skin could break out from rosacea, eczema or psoriasis.
Feed Your Gut
Justin Sonnenburg, a microbiologist at Stanford University who’s focused on how diet impacts bacteria in the gut, recommends eating as many high-fiber fruits and vegetables and legumes as you can. Think whole grains, fruits and vegetables, along with lots of leafy greens. Research has found that a protein in dark, leafy greens stimulates the production of crucial immune cells called innate lymphoid cells in the gut - a prime example of how gut and immune health are intimately connected. Gastroenterologist Will Bulsiewicz, author of The Fiber-Fueled Cookbook, says to choose a few greens that you like, and switch it up, as each plant contains unique phytochemicals that work for specific microbes in your gut.
Sonnenburg says if you don’t give your body enough fiber, you’re left with little to nourish our microbiome. But you want to spread out your meals. Eating sooner than every one-and-a-half to two hours can interfere with the body’s cleansing waves known as peristalsis. Preventing these cleansing waves can lead to an overgrowth of bacteria in the gut.
What About Probiotics?
Here’s where things get interesting. Probiotics, you probably know by now, are good bacteria that are either the same as or very similar to the bacteria that are already in your body. In a recent study published in Nutrients, researchers investigated probiotics’ immune-boosting powers in yogurt. They found that the live bacteria interact with the microbes in our intestines to produce such vitamins as B6, B12 and K; while helping ward off such bad bacteria as E. coli and Salmonella. Probiotics may also enforce our intestines’ natural barrier function, helping to keep viruses and bugs from getting through. And because they’re such potent anti-inflammatories, probiotics have been shown to help clear up skin, reduce allergic reactions, and improve both cholesterol levels and glucose metabolism.
The good news is that while there are many strains, the most effective and potent, lactobacillus acidophilus (l. acidophilus) and/or Bifidobacterium (B. bifidum), are fairly common and easy to incorporate into your daily routine. Either in the form of supplements (powders, pills or gummies) or food that’s naturally rich in probiotics (yogurt, kefir, kombucha and kimchi).
* FYI: The Nue Co.’s Probiotic Plant Protein is one of our current favorite supplements. It mixes a vegan blend of organic pea, hemp and brown rice protein for muscle growth and repair with probiotics and a natural prebiotic to fertilize good bacteria already in your gut.