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Gut Health is Immune Health

Updated: Dec 3, 2020

Illustration by: Ella Byworth

Did you know the microbes in our gut are responsible for shifting our immune response and regulating the overall level of inflammation in our bodies? In addition, they make it possible for us to assimilate essential nutrients critical to the health of our immune, digestive, and nervous systems.

The gut is central to our immune system. So cultivating a healthy gut will inevitably lead to a more regulated immune system. 

Let me elaborate by first explaining what the immune system is...

It’s hard to visualize what our immune system actually is because it doesn’t have a major organ associated with it like how the heart is associated with the cardiovascular system or the brain with the central nervous system. Instead, we can start thinking of our immune system as a vast network spread throughout our bodies. This vast network consists of lymph vessels and lymph nodes in which immune cells travel. 

There are two branches of the immune system (innate and adaptive) that work in concert to protect the body from not-self (pathogens) and help quell inflammation (like from a broken ankle). I’ll be discussing these two branches of the immune system more in depth in another blog post!

GALT and the Mucosal Immune System

Around 80 percent of our immune system is associated with our gut, specifically the colon or large intestine. Immunologists call this part of the immune system the “gut-associated lymphoid tissue,” or GALT. GALT is made up of immune cells (B and T lymphocytes, macrophages, antigen-presenting cells) and epithelial tissue that act as a sort of filter searching for a potential pathogen in the foods and drinks that we eat. 

Our GALT does not stand alone as the only line of defense against pathogens in our gut. It is protected by a layer of mucous churned out by colon cells. Colon cells, when nourished by fiber-rich carbohydrates that we get through our diet, will produce a lot of mucous constantly. This goo serves multiple purposes: 

  1. It is a protective barrier that prevents pathogens from getting too close to the GALT (colon cells can add antibacterial compounds to mucus that deter pathogens from attaching to the colon wall).

  2. It provides a food source for gut bacteria (chemically, the mucus is a carbohydrate).

If there is a breach in the mucosa of our gut, pathogens or partially digested foods (attributed to “leaky gut”) can enter the blood stream causing inflammatory havoc in our bodies. When inflammation goes on for too long, this can lead to chronic autoimmune issues.

When gut mucosal integrity is compromised it can lead to:

  • Dysbiosis (disruption in gut flora)

  • Increased intestinal permeability, also known as “Leaky Gut"

  • Chronic inflammation of the GI

  • Food intolerances

  • Inflammatory bowel diseases

  • Autoimmune diseases

  • Susceptibility to infection

  • Chronic gastritis, dyspepsia

  • Pain associated with HCl secretion, or GERD

  • Ulcers

A Healthy Gut Environment

When we talk about gut health we’re really talking about maintaining the integrity of the gut mucosa. Immunity is partly about the quality of the environment in which microbes live. We take care of our gut environment when we nourish ourselves with nutrient-dense and fiber-rich whole foods (in addition to de-stressing and regulating our nervous systems, getting enough sleep, hydrating, moving our bodies, etc.) which helps to provide nutrients to our colon cells which produce more intestinal mucosa to protect us from pathogens while also feeding our gut microbes who we depend on to assimilate nutrients from our food which ultimately benefit our immune, digestive, and nervous systems. Are you starting to see the connection?

Herbal Therapeutics for Gut Health

Antispasmodics - prevents or ease spasms or cramps in the muscles of the body; these herbs are often carminatives and nervines and so will reduce both physical and psychological tension as well

Ex: Cramp Bark (Viburnum opulus), Chamomile (Matricaria recutita), Ginger (Zingiber officinale), Peppermint (Mentha piperita), Wild Yam Root (Dioscorea villosa)

Bitters / Cholagogues - stimulates flow of bile from the liver, which helps the body to digest fat

Ex: Dandelion (Taraxacum officinale), Gentian (Gentiana lutea), Goldenseal (Hydrastis canadensis), Oregon Grape Root (Mahonia aquifolium), Yarrow (Achillea millefolium)

Carminatives - herbs rich in volatile oils; coordinates and soothes gut contractions; their main action is to soothe and settle the gut wall, thereby easing gripping pains and helping in the removal of gas from the digestive tract

Ex: any herb in the mint family (Mentha spp.), Fennel Seed (Foeniculum vulgare), Ginger (Zingiber officinale), Lemon Balm (Melissa officinalis), Cardamom seed (Elettaria cardamomum)

Demulcents - an herb rich in mucilage and can soothe and protect irritated or inflamed tissue; they are cooling, soothing, healing, and relaxing; in the intestine, demulcents act as a form of soluble fiber and has a bulking and stool softening effect

Ex: Marshmallow Root (Althaea officinalis), Slippery Elm Bark (Ulmus rubra),

Licorice Root (Glycyrrhiza glabra), Comfrey (Symphytum officinale), Rosehips (Rosa spp.)

Nervines - herbs that help to support the nervous system by promoting a calm state; for those whose digestive system is disrupted by emotional upset, nervines can have a positive effect on the nervous system that is followed naturally with relief in the digestive system

Ex: Milky Oats (Avena sativa), Chamomile (Matricaria recutita), Lemon Balm (Melissa officinalis), Linden (Tilia europaea), Wood Betony (Stachys officinalis), Lavender (Lavandula officinalis) 

Vitalist Actions to Support Gut Health

The integration of vitalist practices into daily life can help to reduce stress and anxiety, ultimately promoting a parasympathetic (“rest and digest”) state that will promote healthy digestive function!

☼ Drink plenty of fluids throughout the day. Staying hydrated is vital to keeping your mucous membranes in your GI tract moist and functioning properly. Your weight in pounds divided by half equals an ideal number of ounces of water to drink daily. 

Ex. 125 lbs / 2 = 62.5 oz of water 

☼ Eat while relaxed. Take time to enjoy food--its textures, flavors, how it makes you feel in your body. Chew your food slowly. Close your eyes and give thanks, being aware of the nourishment that is entering your body.

☼ Eat the rainbow. Colorful fruits and vegetables are loaded with antioxidants, vitamins, minerals, and fiber that are all necessary for whole system health!

☼ Get some sunshine! In addition to uplifting mood, vitamin D supports immune system function,* plays a role in calcium, magnesium and phosphate metabolism, and decreases systemic/chronic inflammation along with tightening the junctions between epithelial cells in your intestine!

*Remember that about 80% of your immune system is in your gut!

☼ Breathe deeply and slowly. Take a few minutes in the day to pause and breathe deeply and slowly. Breathing in for 4 counts, holding the breath for 4 counts, and then exhaling for 8 counts. Exhaling for longer than when you inhale helps to stimulate your Vagus Nerve which is responsible for activating a parasympathetic (“rest and digest”) state. Relaxation promotes healthy and balanced digestion. Try this upon waking, in the middle of the day, and before bed.

☼ Spend time in nature. Studies have shown that spending time outdoors can help reduce stress, improve feelings of happiness and cultivate creativity, as well as lower heart rate and blood pressure, boost the immune system and accelerate recovery from illness.



Claud, E. C., & Walker, W. A. (2008). The Intestinal Microbiota and the Microbiome. Gastroenterology and Nutrition: Neonatology Questions and Controversies, 73–92.

Md, P. D., & Loberg, K. (2015). Brain Maker: The Power of Gut Microbes to Heal and Protect Your Brain for Life (Illustrated ed.). Little, Brown Spark.

Montgomery, D. R., & Biklé, A. (2016). The Hidden Half of Nature: The Microbial Roots of Life and Health (Reprint ed.). W. W. Norton & Company.

Prescott, S. L., & Logan, A. C. (2017). The Secret Life of Your Microbiome: Why Nature and Biodiversity are Essential to Health and Happiness (1st ed.). New Society Publishers.

That Gut Feeling: Choosing the Correct Probiotic for Clients in the Herbal Clinic. (2017). Journal of the American Herbalists Guild, 15(1), 49–57.