5 Easy Habits To Improve Your Immune Function

5 easy habits to improve your immune functionAuthor: Lily Mazzarella, MS, CNS

Nothing to buy, no pills to swallow.  The pandemic might be a good opportunity to put these healthy, backed-by-science habits into place.  

Intermittent Fasting   ramp up your metabolism, reduce inflammation and make your immune system more efficient 

Intermittent fasting (IF) is not exactly a fast, nor a particular type of diet.  In IF, you alternate periods of “feeding” with a longer time of not consuming food, aka “fasting”.  One of the most popular and accessible versions of IF is restricting the time of day that you eat any food to 8-12 hours, therefore going 12-16 hours without consuming food.  This fasting period triggers a “metabolic switch” which initiates a series of complex cellular changes that enhance your resistance to disease.   

What does that look like for you?  It’s pretty simple: Depending upon your inclination, daily rhythms, and desired fast duration, you would eat between the hours of say, noon and 8 PM, or 9 AM and 7 PM, and call it quits and brush your teeth—only drinking liquids that don’t contain sugar, like water, tea or coffee (fats like butter or coconut oil are a go in the coffee/tea, but honey, milk and other sweeteners that can trigger insulin release are nixed).  

Some research indicates females may do better with a shorter fast—12-14 hours, whereas males may require a longer fast (14-16 hours) for the same benefits.  The science on IF is impressive: metabolic enhancements including abdominal fat loss, improved insulin sensitivity (blood sugar control), appetite regulation, and increased mitochondrial energy; cognitive benefits—greater mental clarity and protection from neurodegenerative diseases; increased antioxidant status; improvements in gut flora; lowered blood pressure and decreased inflammation.  

I like IF for another reason:  it allows for a longer period of “digestive rest” which can make absorption and elimination more efficient, and free up massive amounts of energy that go in to our digestive processes on a daily basis to be “redistributed” to other systemic functions.  My clients report feeling lighter, brighter and less inflamed with more digestive rest.  

As amazing as it sounds, IF isn’t for everybody—personally, I don’t recommend it to teens, children, or pregnant people, people on certain medications, or clients with adrenal fatigue.  It can take a little experimenting to figure out what fasting period and pattern of food intake during “feeding” is right for you. Generally I recommend a low-glycemic version of paleo, Mediterranean diet (or whatever anti-inflammatory diet works best for your system) while playing around with IF.   

Brushing + Flossing   get the bad bacteria out of your mouth to protect your lungs

We’ve all heard about the links between oral health and cardiovascular disease—but did you know that poor oral hygiene is also linked to susceptibility to pneumonia and other respiratory diseases?  One cubic millimeter of dental plaque contains 100 million bacteria, making the mouth a potential reservoir of infection if the wrong flora take over. High glycemic diets, age (elderly in assisted living and ICU patients are particularly susceptible), and swallowing difficulties are all risk factors for developing the types of mouth bacteria that can harm the lungs.  A 2012 study at Yale University School of Medicine showed that changes in oral flora due to poor tooth care precede pneumonia. In a 2-year study at Sutter Hospital in Sacremento, an aggressive oral hygiene campaign reduced cases of hospital acquired pneumonia by a whopping 70%. Studies at the Center for Veteran Affairs in Salem, VA, and New York University’s Langone Hospital have implemented their own oral health programs, showing similar pneumonia reductions.  

There is emerging evidence that certain species of the bacteria genus Prevotella (found in oral, gut and vaginal flora) are implicated in the development of various infectious and inflammatory conditions, including sinusitis, ear infections, aspiration pneumonia, gout, and inflammatory periodontal diseases.  Some researchers believe that the immune response mounted to some Prevotella species is a major contributor to chronic inflammatory diseases, such as rhemumatoid arthritis. And if all this doesn’t weird you out enough, research at UC Berkeley suggests some Prevotella are hosts to “phages,” large viruses that infect bacteria the way some viruses affect our own cells.  Yikes!

Now is the time to advocate for oral hygiene help for the folks you know in hospitals and assisted living facilities!  And to pick up your floss again, if you had let this healthy habit slip.  

Hot Bath raise your core body temperature by 1-2 degrees  

I’ll state my bias:  I’m a huge fan of the bath.  Research shows that hot baths support blood and lymph flow, aid sleep and relaxation, soothe pain, and may even be an effective tool against depression.  In the form of an Epsom salt soak, baths also act as a great transdermal delivery system for one of my favorite minerals: magnesium. A small study in the UK showed that hot bath therapy had similar effects on improving blood sugar and decreasing systemic inflammation as exercise (however, the study’s authors do not suggest that baths are a substitute for exercise).  

But there are other benefits to a hot bath for immune function:  raising core body temperature stimulates scavenging cells and primes the immune system to fight invaders.  This, of course, is the evolutionary purpose of fever. Fever, defined as an adult temperature of >99 degrees in the morning and >100 degrees any time of day, is a our body’s own way of fighting infection and producing antibodies more efficiently (antibodies are immune proteins that bring along the resolution of illness).  A well-conducted 2014 study showed that fever suppression with substances like acetaminophen (Tylenol) and ibuprofen causes a statistically significant increases in rates of transmission and deaths from influenza viruses at the population level.  

While the passive heating that a bath offers differs from the immune cascade initiated by fever, it still inspires certain T cells and other white blood cells populations to fight infection.  

Forest Bathing   breathe in those phytoncides!  

You probably sense that time in nature is good for you, but you might not know just HOW good.  Decreases in the stress hormone cortisol and in blood pressure, and other improvements in cardiovascular function are well elucidated.  As are various markers of emotional resilience, mood and inflammation (check out The Nature Fix by Florence Williams for a fun and compelling read on the science of the nature-human health connection).  But Forest Bathing, the practice of slowing down in nature for 2-3 hours, has been studied extensively in humans in Japan, to interesting result.   

Researchers suspect that part of the benefit of Forest Bathing on immune function is thanks to “phytoncides,” defense compounds emitted by trees and other plants to protect themselves against insects, herbivores and damage.  Phytoncides have been shown to increase populations and activity of our Natural Killer (NK) cells and anti-cancer proteins. Natural Killer cells target virus-infected and cancerous cells—a very important part of our first-line defenses.  

These “phytoncides,” such as pinene and other aromatic plant terpenes, also tend to smell very pleasing to humans.  If you are not in a position to go into nature, you can avail yourself of the benefits of phytoncides by inhaling aromatic herbs like rosemary, fir, bay or cedar.  If you don’t have access to these plants, you can diffuse essential oil in your home to recreate the effect, preferably while doing something relaxing, like taking a bath (!), or following a progressive relaxation meditation on the Insight Time app.  

Exercise, for good  experience enhanced immunosurveillance with moderate-vigorous exercise of less than 60  minutes 

Is there anything exercise DOESN’T do for us?  Exercise helps prevent cardiovascular disease, as well as neurodegenerative diseases like dementia and Alzheimer’s and bone loss, and helps blood sugar balance and weight management.  It is an effective treatment for depression and anxiety. 

Exercise is one of those keystone habits that initiates a positive cycle:  exercise regularly and experience better mood, energy, digestion, sleep, mental clarity and self-confidence.  The research on exercise immunology, the immune effects of exercise, is equally impressive.  

As long as one does not over-exercise (which can actually suppress immune function), we see benefits like decreased systemic inflammation, decreased stress hormone circulation, and increases in disease-fighting immune factors such as neutrophils, monocytes, NK cells, and cytotoxic T cells.  Not to mention improvements in lymph flow and circulation, which allows for the movement of those infection-fighting cells throughout the body. Exercise also keeps the lungs healthy and strong, which is particularly important when facing respiratory illness.  

At home workouts I love include:  





Oral + Respiratory health: 




Bath & Fever:





Forest Bathing:





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