When we think of immunity, we most often associate it with fighting a cold or the flu. But in 2021, the term has taken on a new meaning, as people evaluate their health and habits from the lens of the virus that causes COVID-19. One of the primary weapons against such illnesses is the microbiome (aka the gut), which when healthy hosts bacterial warriors always at the ready to battle the bad guys.
“Eighty-five percent of our immune system is in our gut,” says Tamara Trebilcock, N.D., of Integrative Health Institutes in Claremont, California. “Basically, our gut is where we first interact with the outside world.”
What many of us don’t realize, she explains, is that the digestive tract is in some sense outside the body. “It is a big, long tube, with an opening at the beginning and the end, and it serves as the barrier to what is going from the outside world into the bloodstream and from there into the different cells of our body. The cells and healthy bacteria in the digestive tract are the army that determines who should be let in and who should not be.”
These cells and good bacteria in the microbiome can actually create physiological responses as they communicate with other cells in the body. But when good bacteria are lacking in the microbiome, communication between our innate immune system and bacteria is disturbed, which in turn can affect our ability to respond to infection, illness and stress. “Stress is a big player in modulating our immune response and our gut microbiome,” Trebilcock says.
4 Steps to Supporting Your Microbiome & Immune System
So, what’s the best way to support your microbiome to have a more robust immune system? Trebilcock offers four key steps to follow.
Step 1: Identify and eliminate any infection, inflammation or dysbiosis—an imbalance or overgrowth in bacteria, for instance. To do so, she says, it’s important to test for food sensitivities. You can work with a naturopath, dietitian or nutritionist to eliminate any foods or allergens that might be promoting inflammation in the gut.
Step 2: Heal the gut and microbiome. If there is inflammation in the gut, treating it is critical to creating a strong immune system. “It’s like there is a fire burning in your digestive tract. It has logs, twigs and trees, and it’s burning. If you take only a few logs away, the fire is still burning,” she says. “You have to stop the fire before you can heal the digestive tract,” she says.
There are numerous herbs and nutrients that will help with healing. Although many people think of probiotics as the supplement for a healthy microbiome, Trebilcock cautions that you first have to check the terrain where the bacteria will live for infection or inflammation, which will prevent the growth of probiotics. Unless probiotics are in an environment where they can flourish, you will be wasting your money, she explains.
Step 3: Do a lifestyle check. Trebilcock emphasizes that sleep, stress management and exercise are critical to our health. “Every three days we make a new lining of our gastrointestinal tract. If we miss out on sleep, we miss out on all of the repair that is needed,” she says. For stress reduction, she suggests simply getting outside. “Being in nature, seeing trees and plants, actually reduces our stress response,” she says. Also, exercise transports oxygen to tissues and can be a predictor of gut microbiota diversity. “It also helps by reducing stress hormones and with mood,” Trebilcock says, noting that even 10 minutes a day does the trick.
Step 4: Once the gut is healed, it’s time to support the neurotransmitters (brain chemical messengers), hormones and healthy bacteria in the gut. “You want to make sure they are all balanced. If stress hormones—such as cortisol—are still affecting the gut, then gut issues can recur,” Trebilcock says, adding, “It is understood that the gut manufactures 80 to 90 percent of the body’s supply of serotonin [a neurotransmitter that influences our mood and GI activity] and 50 percent of our dopamine [known as the feel-good neurotransmitter]. In fact, almost every neurotransmitter can be found in the gut, including GABA [a neurotransmitter that reduces overwhelming feelings of anxiety].” Managing all this, Trebilcock explains, will ultimately help the microbiome function properly.
Foods for Gut Health
The most important foods for your gut should have a good amount of soluble and insoluble fiber. These include beans, peas and lentils; fruits like apples and pears; and artichokes. As far as eating fermented foods—like yogurt, kombucha and fermented vegetables—Trebilcock says it depends. If yeast is present in the gut, then eating fermented foods can just cause inflammation. So, it’s important to evaluate your gut before jumping in with eating certain foods or taking prebiotics or probiotics.
Following are supplements Trebilcock recommends to heal the digestive tract and support a healthy microbiome. For doses, follow label directions or consult a health care professional.
Supplements for a Healthy Microbiome
Deglycyrrhizinated Licorice (DGL)
Hailing from the licorice plant, DGL is a demulcent, meaning it soothes the mucus lining of the digestive tract. “It helps to decrease the stress response in the upper part of your gut and helps to produce stomach acid,” Trebilcock says. While initially, when we experience stress, we produce cortisol, which helps us deal with stress. But when we experience chronic stress, our body’s supply of cortisol depletes. Reduced cortisol can lower the amount of stomach acid we produce and, in turn, lead to a host of digestive issues that can affect the gut lining and our immune response.
Like DGL, slippery elm is a demulcent, acting as a soothing anti-inflammatory for both the small and large intestinal tracts.
Rich in antioxidants, aloe vera works as a gentle anti-inflammatory. It contains amino acids, including salicylic acid, which can reduce pain in the gut.
Lactoferrin (or Lactoferrin-Colostrum)
Lactoferrin is a protein found in both cow and human milk. Colostrum, the first milk a mother produces after a baby is born, is rich in lactoferrin. Lactoferrin is also found in other bodily fluids, including in the respiratory and digestive tracts, and contains antibodies that regulate the immune system.
Originating from the outer shell of shellfish, or made in synthetic form, N-acetyl glucosamine is thought to protect the stomach lining and digestive tract and improve intestinal mucosal integrity. This is a fancy way of saying it helps to keep the intestinal lining smooth by promoting mucous production to prevent damage or drying out and cracking of the stomach lining. Just like when our lips become chapped and more prone to cracking or infection, the same goes for when the lining of the gut becomes irritated or dry. This can lead to inflammation and cracks in the lining that allow bad bacteria and toxins to slip through into the bloodstream.
Prebiotics and Probiotics
Once you have treated inflammation or any bad bacteria overgrowth, support the microbiome with probiotics and prebiotics. Trebilcock recommends a series of probiotics to create robust colonies: lactobacillus, Saccharomyces boulardii and bifidobacterium. After that, Trebilcock will augment with other probiotics, depending on the person’s particular needs and history.