How can we pro-actively boost our immune system before cold and flu season hits in earnest?
By doing an autumn cleanse.
If you’ve been experiencing post-nasal drip, a runny nose, cough, sore throat, fall allergies (ragweed and mold), fatigue, sluggishness, low mood, digestive distress (bloating, gas, constipation, acid reflux), skin issues, or other hormonal imbalances, your body will benefit from a fall cleanse.
Why? Because the key to boosting immunity is to optimize gut health.
How your immune system protects you
Your immune system is a complex system of specialized cells (including a network of white blood cells throughout your body) and organs—and their signaling patterns—that act as your personal bodyguard. In addition to fighting off bacteria, viruses, fungi, parasites and other foreign invaders, your immune system also affects many other systems in your body, from your hormones to your nervous system.
Your skin is the first line of defense. Pathogens also commonly enter the body through mucosal surfaces—such as the lungs, upper airways and the digestive tract—which your immune system vigilantly defends (1).
A healthy immune system recognizes and responds to danger cues, like unhealthy cells with DAMP or danger-associated molecular patterns (2). A weakened immune system—one that fails to activate or to respond sufficiently in the presence of pathogens—leaves the body vulnerable to infection. On the other hand, an overactive immune system that never “turns off”—even after danger has passed, or in the absence of a real threat—manifests as allergic reactions or autoimmune disease, where the immune system mistakenly identifies—then attacks—healthy cells as “foreign invaders” (3).
Chronic inflammation compromises your immune system and can lead to other health problems. Consider ordering the Inflammation Panel. This panel includes 4 markers of inflammation—high-sensitivity CRP, homocysteine, creatine kinase, and uric acid—providing a comprehensive assessment of inflammation, cardiovascular risk, and metabolic health.
The best defense is a strong (gut) offense
Hippocrates, the father of modern medicine, famously said: “All disease begins in the gut.” This is true: up to 80% of your immune system resides in your gastrointestinal tract (4). This is why the foods you eat can help or hinder your immune system. An imbalance in gut bacteria (e.g., more bad bacteria than good bacteria), or an inability to properly break down and digest nutrients, can wreak havoc on your immune system.
We’re often told to eat specific foods to boost immunity—for example, carrots for vitamin A or chicken soup for its mucous-clearing effects. But it is just as—if not more—important to remove foods that cause inflammation and overtax the immune system in the first place.
The following 9 autumn detox tips can help reduce inflammation and strengthen immunity.
1. Detox your mouth! Tongue scrape and coconut oil pulling.
Your mouth is a gateway to your gut. It makes sense, then, that oral health problems can be a symptom of digestive issues and poor immune response.
Upon awakening, check your tongue. Do you see a white coating on your tongue? A thick white coating can suggest a higher toxicity level in the body. Regular tongue scraping removes toxic build-up and bad bacteria that causes bad breath, plaque and poor gum health.
Using a tongue scraper or a teaspoon, scrape your tongue—from back to front—5 to 10 times, rinsing between scrapes.
In India, practitioners of Ayurveda, a 5,000 year old system of natural medicine have used oil pulling as a classic detox therapy to boost immunity. By swishing a fat-soluble oil, like sesame or coconut, toxins are “pulled” from the mouth. Commercial alcohol-based mouthwashes don’t have the same effect because, like antibiotics, they kill all bacteria in the mouth—both good and bad.
Studies have shown that oil pulling—done regularly and combined with brushing and flossing—can effectively remove bad bacteria, improve bad breath, and reduce plaque (5).
Swish 1 tablespoon of organic, unrefined coconut oil in your mouth, ideally on an empty stomach, for 10 to 20 minutes. Spit in trash (NOT sink!). Rinse. Brush and floss.
2. Drink warm lemon water.
Another Ayurvedic tradition is to start the morning with warm lemon water—before eating or drinking anything—for gentle detoxification. The citric acid in lemon helps detoxify the liver and flush toxins out from the digestive tract (6). Lemons (and limes) are an excellent low sugar source of Vitamin C, which boosts the immune system.
Since conventional lemons and limes are often coated with a petroleum-based wax, buy organic whenever possible. Simply combine the juice of half of a lemon with 8 to 12 ounces of boiled filtered water and sip. Since inadequate hydration weakens immunity, be mindful of drinking water throughout the day.
In cooler weather, sipping warm water or room temperature water promotes efficient hydration.
3. Take a break from stimulants, including caffeine, sugar and ultra-processed foods.
A hot cup of coffee can feel like a non-negotiable morning ritual on cool fall mornings, while sugary treats and brightly packaged snacks tempt in the afternoon. Using stimulants to create artificial energy, however, is like whipping a horse when it’s already down—it might rally for another feeble trot around the block. But, eventually, that horse will collapse—no matter how hard you whip it.
In addition to being addictive, stimulants increase your stress hormones, deplete your vitamin and mineral stores, and interfere with sleep—this combination sets you up for weight gain and a weakened immune system.
Instead: switch to herbal tea or green tea (yes, it contains caffeine, but won’t cause the same kind of caffeine “crash”) in the morning. If you hit an energy slump mid-afternoon, try a kale-banana “marathon” smoothie or other whole food snacks (eg, olives, avocado, coconut yogurt) for real energy.
4. Remove common sources of food sensitivities.
A boat with a sizeable hole in it will sink no matter how fast you’re bailing water. It’s the same with your immune system. You can eat more immune-bolstering foods, but as long as you continue eating foods that cause inflammation in the body (e.g., ultra-processed foods, fast food, junk food, Chinese takeout, food truck fare, ice cream, etc.), your immune system will be too busy “putting out fires” to protect you from viruses, bacteria and other pathogens. Plug up that hole in the boat (your immune system) by doing a fall cleanse, which eliminates common sources of food sensitivities—wheat, gluten, dairy, soy, sugar, alcohol—for two to three weeks.
5. Add more green.
A poop a day keeps the doctor away—and prevents toxin build up in the body. To get your bowels moving, eat more greens, rich in insoluble fiber (aka “roughage”). Dark leafy greens, including kale, Swiss chard, collards, mustard greens and romaine, also contain an abundance of hard-to-get minerals, like magnesium, potassium, calcium and iron. Minerals are important basic building blocks for health. Including mineral-rich leafy greens at every meal supports healthy cell function, reduces inflammation and promotes detoxification (fiber helps move toxins and waste out of your body)—all of which bolsters immune system. Green can be delicious! Try this savory Lacinato Kale Salad with Lemon-Tahini Dressing.
6. Swap out processed white carbs for naturally sweet orange carbs.
Cooler weather often triggers cravings for starchy carbohydrates. Our favorite white carbs—bread, pasta, pizza, processed snack foods and baked goods—contain white flour and refined sugars that spike blood sugar and promote belly fat storage. A better choice: naturally sweet orange starch-carbs, like sweet potatoes, butternut squash, pumpkin and kabocha squash, are excellent sources of immunity-boosting vitamin A, vitamin C and dietary fiber. Rich in soluble fiber, winter squash is slowly digested, promoting fullness and stable blood sugar. Try batch cooking roasted sweet potatoes. It is as easy as wash, roast and eat!
7. Take a high-quality probiotic.
A high-quality probiotic can promote a healthy bacterial balance by helping “grow” the good bacteria in your gut. That said, a probiotic is most effective when you are mindful of making anti-inflammatory food and lifestyle choices. Taking a daily probiotic supports your immune system, increasing its resilience and enabling your body to better fight infections.
8. Make quality sleep a priority.
Your body cannot repair, heal or properly detoxify without adequate sleep. Your body perceives chronic sleep deprivation as an ongoing stressor (7). According to a University of Helsinki study, sleep loss triggers an inflammatory response, causing biological changes to the immune system—some can be long-term and may contribute to heart disease and type 2 diabetes (8).
The bottom line: insufficient sleep suppresses immune system function, making it difficult to fight off colds or bacterial infections. Aim for 7 to 8 hours of sleep and be in bed no later than 11pm for optimal immune-protective benefits.
9. Get enough Vitamin D.
Are you bathing in fluorescent light from 9am to 5pm (or longer)? Do you live 40 degrees north latitude (i.e. New York City), where, for at least 6 months out of the year, it is impossible to make sufficient vitamin D from sunshine? Then, it’s likely that you are deficient in vitamin D. According to the Harvard School of Public Health, an estimated 1 billion people worldwide are vitamin D deficient (9). If your Vitamin D3 is low, you will likely have an elevated CRP (C-Reactive Protein), a protein made in the liver, which, according to a 2023 study published in the International Journal of Epidemiology, is associated with systemic low-grade inflammation in the body (10).
Vitamin D is both a vitamin and a hormone. Every single cell in the body requires vitamin D to function—and to detox efficiently. Vitamin D profoundly affects your immune system—it “turns on” anti-inflammatory mechanisms and anti-cancer genes. Studies have shown that an optimal level of vitamin D is associated with decreased risk of cancer and cancer mortality (11).
Though foods like sardines, salmon, eggs and organ meats contain small amounts vitamin D, it is impossible to get adequate vitamin D from food alone. Sunshine is the best way to get vitamin D; but, unless you live near the equator, you will likely need to supplement, especially in the Northeastern U.S. between October and March.
Before you start supplementing…find out what your vitamin D3 level is. You can order your own Vitamin D3 labwork here—this is direct access lab testing; no doctor’s visit required. Or, you ask your doctor to run a 25-hydroxy vitamin D blood test; this is specifically for vitamin D3. An optimal Vitamin D3 level ranges from 60 ng/mL to 80 ng/mL. I maintain my Vitamin D3 level (usually 60 to 70+ ng/mL) by supplementing with this high-quality brand as it synergistically contains both Vitamin D3 and K2 (in correct proportion). I typically take 5,000 IU daily.
Sources
1, 2, 3 “Overview of the Immune System.” Immune System Research. National Institute of Allergy and Infectious Diseases, Dec. 30, 2013.
4 Wiertsema SP, van Bergenhenegouwen J, Garssen J, Knippels LMJ. The Interplay between the Gut Microbiome and the Immune System in the Context of Infectious Diseases throughout Life and the Role of Nutrition in Optimizing Treatment Strategies. Nutrients. 2021 Mar 9;13(3):886.
5 Asokan S, Emmadi P, Chamundeswari R. Effect of oil pulling on plaque induced gingivitis: a randomized, controlled, triple-blind study. Indian J Dent Res. 2009 Jan-Mar;20(1):47-51.
6 “Ayurvedic Health Benefits of Lemon.” Dr. D.Y. Patil College of Ayurved and Research Centre. April 11, 2025.
7 Besedovsky L, Lange T, Born J. Sleep and immune function. Pflugers Arch. 2012 Jan;463(1):121-37. Epub 2011 Nov 10.
8 Aho V, Ollila HM, Rantanen V, Kronholm E, Surakka I, et al. (2013) Partial Sleep Restriction Activates Immune Response-Related Gene Expression Pathways: Experimental and Epidemiological Studies in Humans. PLOS ONE 8(10): e77184
9 “Vitamin D.” The Nutrition Source, Harvard T.H. Chan School of Public Health. March 2023.
10 Ang Zhou, Elina Hyppönen, Vitamin D deficiency and C-reactive protein: a bidirectional Mendelian randomization study, International Journal of Epidemiology, Volume 52, Issue 1, February 2023, Pages 260–271.
11 Holick, M. F. Cancer, sunlight and Vitamin D. Journal of Clinical & Translational Endocrinology. 2014 Dec. Vol 1, Issue 4, pp. 179-186.
