Your gut rules everything inside you. That may not sound like a catchy song at all, but it couldn't be more true. The importance of a healthy gut microbiome has become something of a phenomenon in recent years. Science has shown that beneficial bacteria in the digestive system is connected to everything from immune function to mental health. Here's how probiotics--whether ingested through food or supplements--can promote total body wellness. Here are the major benefits of probiotics:

Your Digestion Is 100%.

When your intestinal microbes are balanced, the most immediate effect is optimal digestion. That means issues like diarrhea, constipation, gas and heartburn are nada, and you're better able to absorb nutrients from food. It's also easier for the body to burn carbs, which helps keep your weight in check and can cut the risk of obesity and type II diabetes.

Immunity Gets A Boost

The digestive tract houses 70 percent of your immune system, so it makes sense that probiotics can fight inflammation and infections. Loading up on good bacteria is serious business; studies have linked imbalanced gut flora to diseases like metabolic syndrome, heart disease, Alzheimer's, colorectal cancer, stomach cancer and lymphoma.

Mental Health Is On Point

One of the most impressive things about probiotics is the relatively recent discovery of the gut-brain connection. Ninety percent of serotonin, the "feel-good" hormone, is produced in the intestinal tract--no wonder more and more scientists believe bacteria plays a role in regulating mood.

A study of mice showed up that stripping them of microbes induced anxiety--their cortisol (stress hormone) levels increased as BDNF, a protein in the brain that fights depression, decreased. Once they were given probiotics, their cortisol levels dropped, and GABA, an anti-anxiety neutrotransmitter, increased naturally. It works on humans, too. A study out of the College of William & Mary and the University of Maryland found that just eating fermented foods could curb social anxiety.

Your Skin Glows

Anecdotally, some proponents believe probiotics can improve the appearance of skin. Acne, rosacea, and eczema are often the result of inflammation, so addressing digestive issues could clear things up.

How To Get Probiotics

We know what you're thinking: you can't wait to ingest some good bacteria, like, right now. Well, got any plain yogurt or pickles in the fridge? It's that easy. Fermented foods like sauerkraut, sourdough bread, miso, kimchi, and the aforementioned plain yogurt and pickles have naturally occurring probiotics (See: How To Make Pickles).

It's also smart to pair these foods with ones that have prebiotics, which feed the friendly bacteria. Some cultured foods like kefir have both. Other sources of prebiotics: whole grains, garlic and onions. It never hurts to take a probiotic supplement, too. Experts generally recommend maintaining around 80 to 85 percent good bacteria in your belly--that's hard to measure, so the more the better. Look for one that boasts 15 billion to 100 billion CFUs (colony forming units) on the label, and with at least three types of strains (e.g. Lactobacillus acidophilus, Saccharomyces boulardii, Bacillus coagulans, B. longum, B. bifidum), because variety will only broaden the benefits.

No need to fear bacteria. In fact, trapping yourself in sterile indoor environments can limit the diversity of your gut microbiome. Open a window and welcome some of those microbes in--they're good for you!

About the Author

Dana is a Los Angeles–based freelance writer and editor with a focus on eco lifestyle and beauty—from vegan cooking to natural, cruelty-free skin care. Also a wildlife enthusiast, naturalist, and advocate for conservation and environmental stewardship.