More than ever, we are recognizing how the state of our gut and microbiome is connected to our immune system and overall quality of life. The gut lining is one of the body's most essential defence barriers, and when this barrier is compromised, it becomes more permeable. As a result, the immune system– of which 70% is located in the gut– reacts, increasing the risk for systemic problems, including immune dysfunction. Therefore, to maintain a healthy immune system, gut health, and the health of your microbiome, is the first thing to get on track to help your body tackle viruses like the common cold and flu.
We know the importance of frequent hand washing, nutritious diets, regular exercise, and plenty of rest when viruses are making their rounds. Still, these might not be enough if you lack the nutrients needed for a robust immune system.
When taking proactive steps to protect your immunity, follow these steps to nourish the gut-immune connection:
1. Identify and remove triggers of gut inflammation. Processed food and foods high in sugar have been shown to compromise the gut lining and impact the balance of the gut microbiome, contributing to a “leaky” gut.[1] This increase in permeability leads to systemic inflammation, putting a strain on the immune system. Consider giving your gut a break by eliminating highly processed foods and those lacking healthy fibre. Cutting out sugar, gluten, dairy, corn, and soy for 4-6 weeks, is an ideal amount of time to clear these common triggers of gut inflammation and help your immune system stay strong.
2. Balance stress. Both acute and chronic stress can impair gastrointestinal function and immune function and increase susceptibility to illness.[2] By suppressing your parasympathetic nervous system– the one responsible for resting and digesting– chronic stress can really take a toll. Altering digestive enzyme and stomach acid secretions will impair your digestive and absorptive abilities, ultimately impacting your microbiome and hence your immune system.
3. Question unnecessary medications. Medications often overused include nonsteroidal anti-inflammatory drugs (NSAIDs), antacids like proton-pump inhibitors (PPIs), and antibiotics. It is important not to change or discontinue medications before you speak with your health care provider but be aware that the overuse of these can cause lasting digestive and immune effects by impairing the gut lining, suppressing your digestive abilities, unnecessarily killing good bacteria, and leading to nutrient deficiencies.
4. Nourish the gut lining. The amino acid glutamine is the main fuel for the cells that line the digestive tract. Studies have shown that this amino acid can positively affect gut health by supporting the gut microbiome and the gut lining’s integrity and by modulating inflammatory responses. In order to provide benefit, look for a powdered and micronized L-glutamine, providing a highly absorbable form and an easier way to take the recommended 5 grams per day.
5. Rebalance the microbiome. The gut microflora signals the immune system to rev up antibody production during times of stress. It also helps inhibit the growth of pathogens within the digestive tract.[3] Probiotic supplements have been shown to temporarily modify gut flora, helping to shorten the duration of respiratory tract infections by up to 1.9 days and reducing their incidence by 47%.[4]
6. Try a fibre supplement. Fibre has been touted for several health benefits including weight loss, cholesterol and blood sugar balance, and healthy bowel function. A 12-week randomized, placebo-controlled, double-blinded trial published in 2022 showed that partially hydrolyzed guar gum reduces cold-like symptoms in healthy adults.[5] This water-soluble dietary fibre is thought to influence immune function, suppress cold-like symptoms, and prevent infections through the production of short-chain fatty acids (SCFAs) which regulate immune functions through their receptors.[6]
While there’s no cure for the common cold, supporting gut health can profoundly impact immune function. Implementing these tips can help you stave off illness and help you feel better faster!
[1] Deters, Brett. & Saleem, M. (2021). The role of glutamine in supporting gut health and neuropsychiatric factors. Food Science and Human Wellness, 10(2), 149–154. [2] Diop, L., Guillou, S. & Durand, H. (2008). Probiotic food supplement reduces stress-induced gastrointestinal symptoms in volunteers: a double-blind, placebo-controlled, randomized trial. Nutrition Research, 28(1), 1–5. [3] Galdeano, C.M., Cazorla, S.I., Dumit, J.M., et al. (2019). Beneficial effects of probiotic consumption on the immune system. Annals of Nutrition and Metabolism, 74(2), 115–124. [4] Lenoir-Wijnkoop, I., Gerlier, L., Roy, D., et al. (2016). The clinical and economic impact of probiotics consumption on respiratory tract infections: Projections for Canada. PLoS One, 11(11), e0166232. [5] Sakai, S., Kamada, Y., Takano, H., Ichikawa, M., et al. (2022). Continuous partially hydrolyzed guar gum intake reduces cold-like symptoms: a randomized, placebo-controlled, double-blinded trial in healthy adults. European review for medical and pharmacological sciences, 26(14), 5154–5163. [6] Rooks, M.G. & Garrett, W.S. (2016). Gut microbiota, metabolites and host immunity. Nature Reviews Immunology, 16, 341–352.