When it comes to optimal function throughout your body, it all starts in the gut. Considering that the gut is home to roughly 70% of your immune system, when your gut is bacterially well-balanced, it’s well-equipped to fight off common pathogens, preventing them from running amok and dragging your health down. And your essential ally in cultivating that healthy balance are prebiotics foods. Here’s a topline on how to get more of them on your plate and into your gut:

Probiotic power – and prebiotic power.

By now, most people are familiar with the idea that fermented probiotic foods (think sauerkraut, kimchi, natto, apple cider vinegar, etc.) and probiotic supplements are good for the gut, in turn helping to keep immunity strong. Probiotic foods help ‘seed’ the gut, adding beneficial bacteria, which helps keep ‘bad bacteria’ in check, aids digestion and keeps nutrient absorption humming.

But, probiotics are only part of the story. There’s another ‘biotic’ in the gut-supportive mix, namely the less talked about prebiotics. These are plant fibers that feed the beneficial bacteria (like, for example, the lactobacilli and bifidobacteria) in the gut.

What are prebiotics – and what are they up to?

In simplest terms, prebiotics are the dietary fibers which we human types can’t actually digest. But, you might ask, what’s the point of eating them? Well, it’s not about you, per se, it’s about nourishing the community of creatures living inside you, namely, the billions of bacteria that live in your gut, the microbiome, which play a huge role in keeping us well. Think of prebiotics as the fertilizer that enables your gut garden – and immunity – to thrive.

Prebiotics bring a lot to the table – and your gut.

What’s interesting about prebiotics is that they do more than just make your ‘microbiome’ happy, they also promote a lot of health-supportive “downstream” effects throughout the body, including your brain. For example, prebiotics feed the specific, beneficial gut bacteria responsible for producing a substance known as butyrate. And butyrate is a short-chain fatty acid that has promotes gut health, while also helping to stabilize blood sugar levels and reduce the risk for certain types of cancers, and more.

In addition, according to a recent study from the University of Surrey in the UK, prebiotics also seem to play a helpful role in easing anxiety, promoting mental health and well-being. Stable blood sugar? Reduced cancer risk? Better mood? Count us in – and make our prebiotics a double, thanks.

Prebiotics can help move pounds.

Another upside to a diet that’s rich in prebiotics? Less hunger. All that regularity-promoting indigestible fiber helps fill your belly and curb hunger. The increased satiety means fewer cravings, and less caving into bad guys like sweets, sugar, simple carbs and processed foods which, by the way, are crappy at keeping your belly full (or, for that matter, healthy). But, keep in mind, it’s not a case of one salad and you’re good till next month. Just like pets and houseplants, you need to keep feeding your gut prebiotics to thrive. So, keep the prebiotics – and all their fermentation-facilitating indigestible fiber – flowing at every meal.

Pile on the plant-based prebiotics.

The good news about prebiotics is that they’re also tasty -- you’ll find most, if not all of them, in the produce aisle. I encourage you to add a few more to your plate, ideally every day, and if possible, try to buy organic or fresh from the farmers’ market if possible.

To keep costs in check on some of the items below, shop according to the Environmental Working Group’s Shoppers Guide to Pesticides in Produce to help you identify which items are OK to buy from conventional (non-organic) sources and which are best bought from healthier sources.

At the top of the must-eat list are foods loaded with inulin and oligosaccharides, the nondigestible carbs. Remember, they’re not digested, they’re fermented by our bacteria friends, in the process creating by-product compounds that support optimal function, in the gut and everywhere else in the body. Among the prebiotic plant-fiber super-stars:

• Almonds
• Asparagus
• Chicory root
• Dark leafy greens
• Dandelion greens
• Endive
• Garlic
• Jerusalem artichokes or sunchokes
• Jicama
• Kiwi
• Leeks
• Mushrooms
• Onions

Toss in a little ‘resistant starch’ while you’re at it.

In addition to the above, you can always up your intake with prebiotic ‘resistant starch’ foods, as in, the starches that don’t raise glucose levels and aren’t digested in the small intestine. Instead, resistant starches move down to the large intestine where the fibers slowly ferment (which means less gas for you), and act as a prebiotic, encouraging the production of those all-important short chain fatty acids. Resistant starches also help increase feelings of fullness, ease and even prevent constipation, and reduce colon cancer risk. So, try working moderate amounts into your repertoire as well. Among the resistant starches to consider:

• Lentils, black beans, kidney beans and chickpeas
• Green/under-ripe bananas
• Tiger nut flour for baking

Eat – don’t toss – your stalks and stems!

Broccoli and cauliflower florets may be Instagram-worthy on your plate, but the stalks and stems are where it’s at from a prebiotic POV. Same goes for red chard stalks, kale and collard green stems — so don’t throw them out! Those tough, less photogenic veggie parts play an important role in gut health by giving your good bacteria something, namely cellulose fibers, to chew on. By all means, enjoy the florets, but instead of tossing the stalks and stems, slice them up into strips, munch on them raw, crudité-style or, chop them up small, and give ‘em a light steam with a mix of other veggie leaves and florets.

Your prebiotic prescription: clean, whole foods, and plenty of them.

If you’re not used to eating a lot of prebiotic foods, start slow and up the dose toward optimal levels over the course of a few days or weeks. Assuming you do not have major gastrointestinal problems (like Crohn's, IBS, etc.), try working your way up to 3 – 5 servings of prebiotic foods per day.

Keep in mind, in general, raw foods will retain more prebiotic fiber than cooked, so opt for raw whenever possible. In the case of tougher-to-eat-raw foods like asparagus, very lightly steaming or home-fermenting can make them easier to incorporate into meals. For leafy greens like kale, chop as finely as possible and/or prep with a light sauté.

Though ideally you should get the majority of you prebiotics from whole foods, for those times when you’re falling short on your intake, you can supplement with a high-quality, non-GMO, organic prebiotic powder – and if it’s gluten, soy and dairy-free, even better.

BOTTOM LINE: When it comes to your prebiotics (as well as your probiotics) variety is king. The wider the range of fibers we eat, the more varied the bacteria in our guts will be, offering us more protection against the bacteria we don’t like. Our gut is like our planet -- diversity is the key to maximum resilience and a healthy future, so care for it well!