Immune health is something most of us take for granted. When your immune system runs smoothly, it’s likely you don’t even notice it.
Yet, every day you are exposed to millions of invaders — viruses, bacteria, and other microscopic pathogens. Due to this relentless assault on your health, your body relies on your immune system protection and good health.
Your immune system is not a discrete part of your body. It’s an entire network of cells, tissues, and organs, all working together to defend against health threats.
Many people ignore their immune health until something negative happens. But you can choose more wisely by becoming pro-active — starting today. You can make some simple lifestyle changes and better choices for optimal immune health before something challenges your health.
To help, in this article you will find 10 strategies to boost your immune health naturally:
#1. Reduce Inflammation for Immune Health and Disease Prevention
Way back in 2004, Time Magazine’s cover featured the “secret killer” — inflammation. Around that time, researchers were discovering a shocking link between chronic inflammation and major killer diseases: heart disease, cancer, Alzheimer’s, and many others.
What is Inflammation?
Inflammation is one of your body’s crucial defense mechanisms. Your immune system uses it to protect you from infection, toxins, damaged cells, injury, and other factors. It helps your body repair damage done to cells and organs.
You’ve experienced inflammation whenever you have a wound or muscle strain. Your body responds with signs such as redness, heat, pain, swelling, and sometimes loss of function.
This is acute inflammation, which is a short-term response to heal you. This is a localized and beneficial process.
Unfortunately, the immune system can go into overdrive. This triggers a type of “smoldering fire” in your body. A chronic, low-level inflammatory state. And of course, this is not beneficial.
This chronically inflamed state can go undetected for years — even decades — before it erupts into some type of full-blown disease. Smoldering inflammation affects your body system-wide rather locally, as with acute inflammation.
This dysfunctional immune-centered process causes the release of a cascade of pro-inflammatory chemicals researchers have now linked to major chronic diseases, even our major causes of death.
Some of these chemicals are cytokines, small proteins released by cells that play a role in cell signaling. Cytokines are considered immunomodulating agents. This means they regulate immune system function. They help cells communicate with each other in immune responses. And they stimulate the movement of immune cells toward the site of inflammation.
It’s important to realize that cytokines can be both pro- and anti-inflammatory, depending on the situation.
Pro-inflammatory cytokines include interleukins (IL), tumor necrosis factor (TNF), and many others. To remain in good health, you need to maintain a balance between your pro-inflammatory and anti-inflammatory cytokines.
Chronic inflammation leads to problems via many different mechanisms, including excessive free radical formation and the damage these free radicals do to cells in the body.
Inflammation and Aging
One theory of aging, called “inflamm-aging,” suggests that the aging process results from a decreased ability to cope with physical and emotional stressors, escalating this pro-inflammatory state.
Along these lines, health experts generally believe that the key to longevity is to reduce this chronic, low-level inflammatory state. At the same time, the body needs to retain the ability to respond in a healthy way with an acute immune response when necessary.
Interestingly enough, people who live to be 100 or more demonstrate genetic markers giving them improved control over the inflammatory process. That’s certainly no coincidence. However, as you’ll see shortly, you can’t rely on genetics to give you an edge when it comes to immune health and a long life.
Inflammation, Chronic Disease, and Immune Function
Let’s consider heart disease. Aging is a big risk factor for cardiovascular disease, since the body tends to become progressively inflamed as the years pass.
Increasing oxidation takes place, which is the process free radicals use to cause cell damage. Oxidation triggers an immune reaction, which in turn triggers a cascade of pro-inflammatory chemicals at the site of a damaged artery.
This is an immune reaction in which white blood cells called T-lymphocytes and macrophages migrate to the site of damage. They embed themselves in the artery wall and try to gobble up the invaders. During this process, they release molecules that help form the plaque linked to heart attacks and strokes.
Inflammation does not only contribute to cardiovascular disease. Scientists now believe that chronic inflammation is at the root of many cancers, Alzheimer’s, type 2 diabetes, some arthritic disorders, Crohn’s disease, and many others.
By now, you can easily see how important it is to reduce the level of inflammation in your body, particularly if you are middle-aged or older. Since inflammation works hand in hand with your immune system, you can boost your immune health by using anti-inflammatory strategies.
Are You Making Pro-Inflammatory or Anti-Inflammatory Lifestyle Choices?
Many factors put you at risk for maintaining or escalating a state of chronic body inflammation.
- Being overweight or obese (particularly with visceral or ‘belly’ fat)
- Chronic, unrelenting stress
- A sedentary or inactive lifestyle
- Poor overall diet
- Poor quality sleep
- Gum disease
- Low levels of sex hormones
- High blood sugar
We will discuss many key factors in this article which are important to immune health — and have the side benefit of reducing body inflammation. Factors such as:
- Cutting down on sugar consumption
- Maintaining good dental and oral health
- Taking measures to reduce your stress level
- Getting regular moderate exercise
- Getting enough high-quality sleep
- Maintaining an optimal weight
- Eating plenty of anti-oxidant containing fruits and vegetables
Another Tip Regarding Inflammation
The CRP or C-reactive protein test is a nonspecific measure of inflammation in the body. You can ask your doctor to run this relatively inexpensive test at your next physical exam. While it doesn’t tell you where the problem is located, it provides a benchmark of how inflamed your body is.
#2. Reduce Stress to Improve Immune Function
For generations, folk wisdom has recognized that stressful events take a toll on health and well-being. It has taken modern science time to catch up, but over the last four decades, scientists have realized how stressful situations and negative emotions affect the immune system.
The New Scientific Field Called PNI
A whole new field of study has been created, one called psychoneuroimmunology (PNI). PNI examines the interactions between your immune system and the central nervous system in your brain and spinal cord). What PNI research has discovered is that the immune system and brain are intimately linked through a number of pathways.
Both systems — immune and CNS — produce small molecules that serve as messengers between the systems. The immune system uses microscopic proteins known as cytokines to communicate with your CNS.
Cytokines, Inflammation, and Stress
Many studies have focused on the release of cytokines as a response to both psychological and physical stress. Specific cytokines are released by cells in the immune system, but those produced in response to stress are generally inflammation-producing.
When you are under physical or emotional stress, your body also releases hormones such as adrenaline, which bind to cell receptors telling the body to produce these pro-inflammatory cytokines.
One pro-inflammatory cytokine known as IL-6 influences immune system responses. It stimulates the activity of certain immune T cells functioning as links between the innate and acquired aspects of our immune system.
Stress, Immune Function, and Disease
Production of IL-6 and other pro-inflammatory cytokines can be stimulated by stressful situations, negative emotions, depression, and anxiety.
Moreover, as many studies including a 2009 review in the journal Perspectives ion Psychological Science notes, overproduction of IL-6 has been associated with an entire spectrum of age-related disorders, including heart disease, arthritis, type 2 diabetes, certain cancers, Alzheimer’s, and many others.
And when it comes to stress-related immune dysfunction, negative emotions can contribute to:
- Increased vulnerability to infection
- More prolonged infection
- The reactivation of latent viruses
- Delayed wound healing
- Reduced immune response to vaccines
Older Adults More Susceptible to Stress-Related Immune Dysfunction
Unfortunately, older individuals or those with existing health conditions are more vulnerable to stress-related immune changes.
A 2002 study done by researchers at John Hopkins School of Medicine found that even chronic mild depression can suppress an older person’s immune system. Study subjects in their early 70’s with chronic mild depression demonstrated weaker immune cell responses. The immune response remained down even 18 months following the study.
Another complicating factor is that older individuals are more at risk for loneliness, emotional grief, social isolation, and other stress-producing life situations.
Helpful Remedies for Stress
Health experts including the Mayo Clinic and others suggest a number of helpful lifestyle strategies to deal with ongoing stress and/or anxiety. Here are ten of them:
- Remain physically active. Get into a routine that keeps you doing something active nearly every day. Exercise is a powerful way to reduce stress. It not only helps with mood issues, but can contribute to overall health.
- Eat stress-busting foods. Stress-reducing foods suggested in the Journal of Nutrition & Food Sciences include spinach, blueberries, broccoli, fish, bananas, walnuts, and oranges, to name a few.
- Avoid alcohol, smoking, and recreational drugs. These substances can lead to or even worsen anxiety. If you are unable to quit on your own, talk to your doctor or seek out a support group that can help you.
- Avoid or cut back on caffeinated beverages. Excessive caffeine can aggravate anxiety.
- Use relaxation and stress management techniques. You can learn simple visualization techniques, yoga, meditation, or other techniques to lessen anxiety.
- Make quality sleep a priority. Sleep experts recommend 7 to 9 hours of quality sleep each night to avoid a sleep debt. If you continue to suffer sleep issues, insomnia, or snoring, talk to your doctor.
- Discuss your stress levels with a professional. Talking with a counselor or trusted friend can relieve stress and give you a more positive outlook on your situation.
- Keep a journal. This can help you identify the issues causing your stress, so you can determine a plan of action.
- Take frequent 5-minute stress relief breaks. Stress builds up throughout the day, so taking short breaks can lower your overall stress level.
- 10. Use nutritional supplements with stress-relieving benefits. For example, probiotics with their friendly bacteria have the potential to benefit mood disorders. And the Ayurvedic herb ashwagandha, which lowers cortisone levels, is known for its stress-lowering effects.
#3. Get More High Quality Sleep for Better Immunity
More than 1/3 of adults in America don’t get enough sleep on a regular basis. That’s according to a study reported in 2016 in the CDC’s weekly report.
How much sleep do you really need?
According to the Mayo Clinic, adults require 7 to 9 hours of sleep per night for optimal health. And contrary to popular thought, older adults need just as much sleep as younger adults.
As you might expect, sleep exerts a powerful influence on immune function.
Folk wisdom tells us that having an infection such as a cold or flu will make us tired and increase our desire and need to sleep.
And of course, getting a good night’s sleep is commonly referred to as ‟the best medicineˮ for an infectious disease. Along these lines, it makes common sense that persistent sleep loss can weaken our body defenses and make us more prone to catching a cold or some other infection.
But what does the research say? A literature review reported in the journal Physiological Reviews confirms the presence of a bidirectional link between sleep and immunity.
In other words, activation of the immune system alters sleep. And in turn, sleep affects the innate and adaptive parts of the body’s immune system.
Sleep and Inflammation
Stimulation of the immune system by pathogens triggers an inflammatory response. This can disrupt how long or deeply one sleeps. The enhancement of sleep during an infection is believed to help with immune system defense.
On the other hand, sleep disturbance or deficiency can cause the chronic, low-grade inflammation discussed earlier, that has been linked to conditions such as heart disease, diabetes, obesity, and neurodegenerative disease.
Sleep affects several immune system parameters.
- Sleep is linked with a reduced risk of infection
- Sleep can improve infection outcome
- Sleep can improve the response to vaccination
- Sleep helps modulates the level of inflammation
How Poor Sleep Alters Immune Function
A 2019 German study reported in the Journal of Experimental Medicine, identified a mechanism that links sleep to immune function.
When specialized immune T cells recognize pathogens, they activate microscopic proteins called integrins. These integrins allow the T cell to latch on to their targets. In short, researchers found that good quality sleepers had higher levels of integrin activation, which boosts the function of T cells.
Other studies have looked at the role of cytokines such as IL-6 (that you read about earlier in connection with stress) in sleep. Scientists believe that numerous cytokines have sleep regulatory properties.
Many studies have been performed on the effects of sleep on autoimmune inflammatory disorders such as rheumatoid arthritis (RA). About half of RA patients report sleep issues. Researchers attribute this, at least in part, to inappropriate production of different cytokines.
Sleep Strategies for Better Immune Health
If you have trouble falling asleep or remaining asleep, here are some strategies health experts recommend that could help:
- Maintain a regular schedule for bedtime and waking. Your body uses a 24 hour “internal clock” called a circadian rhythm. Going to bed and waking at around the same time each day (even on weekends) helps keep your circadian rhythm from getting thrown off.
- Keep a regular pre-sleep routine. Many people sleep better when they maintain a consistent “winding down” or pre-sleep ritual. Certain activities can promote relaxation and prepare the body for sleep, such as reading, gentle stretching, journaling, meditation, or the use of aromatic essential oils such as lavender.
- Minimize sound and light in your sleeping area. Environmental factors such as these can disrupt your sleep quantity and quality. Darkness is a signal to your brain to release melatonin, which has a sleepy and calming effect. So it’s a good idea to reduce your exposure to light before bedtime, including light from your TV, computer, or other electronic devices. Create a dark space by using blackout shades or by using an eye mask. Since noise can also prevent sleep, you may need a fan or white noise machine to block out sounds if you have trouble sleeping.
- Make yourself comfortable. You spend about 1/3 of your life asleep. That’s why it’s sensible to invest in a good quality mattress and pillow that makes you feel comfortable and relaxed. You may need to lower your thermostat several degrees. Most research suggests that 65 degrees is the best sleeping temperature.
- Go easy on caffeine and alcohol. Limit caffeine consumption for eight hours before bedtime. Avoid alcohol near bedtime as well. It may aid you in falling asleep, but can increase your chances of waking up in the night once its effects wear off.
- Review your medications and pain levels with your doctor. Particularly if you are older, you could have pain or be taking medications that can affect sleep quality. Check with your doctor to see if they could be adding to your problem.
- Limit fluids. To minimize nighttime trips to the bathroom, stop drinking fluids within 2 hours of bedtime.
- Watch that napping. Limit any daytime napping to 20 minutes to ensure you maintain a good sleep cycle. If napping ends up making you less sleepy at bedtime, it’s better to avoid naps altogether.
- Snorers need to be careful. Snoring doesn’t only contribute to a loss of sleep for you or your bed partner. It can be related to a potentially dangerous condition called sleep apnea. If you snore, check in with your doctor.
- Consider melatonin or other sleep-promoting supplements. Melatonin is a hormone regulating your sleep cycle. It is produced by your brain’s pineal gland, but is also available in supplement form. Since it promotes relaxation, people with insomnia or jet lag often use it. At the proper dose, melatonin is considered safe. However, it can interfere with some medications, so check with your doctor before using melatonin.
#4. Avoid Toxic Personal Care Products and Cleaners
According to the Natural Resources Defense Council, most of the 80,000+ chemicals contained in products used by Americans have not been sufficiently tested for their health effects.
These chemicals lurk in thousands of everyday products and items, including furniture, cosmetics, household cleaners, toys, packaging, building materials, and even food.
And unfortunately, medical researchers are linking more and more of these chemicals to diseases, including those diseases related to the immune system.
Your immune system is designed to protect you from disease and infection. And at its core lies the ability to discern between self and non-self — in essence, what is “you” and what is “foreign.”
When the immune system fails to make this distinction, your body produces antibodies that attack normal cells by mistake. What results is a misguided attack on your own body, leading to the damage we know as autoimmune disease.
With autoimmune disease, regulatory immune T cells are no longer able to keep the immune system in check. Emerging science suggests that impairment of immune B cells play a role in the development and progression of autoimmune conditions.
Another factor connected to autoimmune disorders is what’s called “leaky gut syndrome.” Toxins and other harmful substances can pass through a permeable gut wall and into the bloodstream, triggering abnormal immune activity and inflammation.
Scientists have identified over 80 known types of autoimmune diseases. They affect more than 23.5 million Americans, and are a leading cause of death and disability, particularly among women.
Some autoimmune diseases are fairly common. For example, the autoimmune disorder rheumatoid arthritis affects 1.3 million Americans. Other examples of autoimmune diseases include:
- Hashimoto’s disease (underactive thyroid)
- Grave’s disease (overactive thyroid)
- Multiple sclerosis
- Myasthenia gravis
- Inflammatory bowel disease
- Type 1 diabetes
Environmental Exposure Fueling Autoimmune Diseases
According to Douglas Kerr, M.D., Ph.D. Professor at Johns Hopkins School of Medicine: “There is no doubt that autoimmune diseases are on the rise and our increasing environmental exposure to toxins and chemicals is fueling the risk.”
So what kind of chemicals are linked to autoimmune disorders and other forms of immune dysfunction?
Endocrine Disrupting Chemicals
One category of potentially harmful substances are endocrine disrupting chemicals (EDCs).
EDCs are added to plastic packages, beauty products, toys, and so many other products they are now ubiquitous in the environment — and in our food and drinking water.
Research has shown that EDCs including phthalates, triclosan, bisphenols, parabens, and others impact the development, function, and lifespan of various immune cells.
Take phthalates, for example, used since the 1930’s in a diverse number of products:
- Shower curtains
- Plastic packages
- Children’s toys
Hundreds of millions of tons of phthalates are produced every year. They are added to products during manufacturing, and easily leach into the environment.
Research reported in the journal PLoS One in 2015 suggests that both the innate and adaptive immune systems are influenced by phthalates. In studies, they led to impaired cytokine production and disruption of normal inflammatory processes.
Triclosan has antimicrobial properties, and is thus added to hand soaps, laundry detergents, deodorants, toothpaste, and many other products. Bisphenol A (BPA) is used in plastics and epoxy resins, including food containers.
Research shows that both triclosan and BPA can negatively impact human immune function.
And while studies have linked endocrine-disrupting chemicals to a number of immune-related diseases, they have also been linked to hormone-dependent cancers, reproductive disorders, and neurodevelopmental disorders.
PFCs in Consumer Goods
Another group of toxic chemicals is known as perfluorinated chemicals (PFCs), found in common consumer products:
- Non-stick cookware
- Stain-resistant clothing coatings
- Microwave popcorn bags
Of course, they leach into our food and water and eventually into our bloodstream and body.
A Harvard study published in 2012 in the Journal of the American Medical Association found that children exposed to PFCs in the womb as a result of their mother’s exposure suffered impaired childhood immunity and vulnerability to disease. The study authors cite the “immunotoxic potential” of PFCs.
Allergies, Eczema, and Asthma
Known collectively as atopic diseases, allergies, asthma, and eczema are characterized by an overactive response to immune antibody production.
Asthma is characterized by chronic inflammation of the respiratory airways that can be triggered by an allergen of some type. Allergic responses have traditionally been considered different from autoimmune reactions. More recently, according to an article in Expert Review of Clinical Immunology, studies are showing that asthma may also have an autoimmune connection.
The incidence of atopic allergic disease is on the rise. One suggested reason is exposure to certain chemicals, pollution, and household cleaning products.
VOCs Inside and Outside the Home
Many cleaning supplies or household products release dangerous chemicals, including gases known as volatile organic compounds (VOCs).
VOCs (and other chemicals such as ammonia and bleach) found in cleaning supplies contribute to chronic respiratory problems, allergic reactions, and asthma. Some VOCs can cause cancer.
VOCs can be found both indoor and outside. Some familiar VOCs include benzene, formaldehyde, and toluene.
Sources of VOCs include:
- Building materials
- Varnishes and finishes
- Paint and varnish
- Caulks, sealants, and adhesives
- Flooring, carpet, and pressed wood products
- Home and personal care products such as cosmetics and deodorants
- Cleaners and disinfectants
- Air fresheners
- Dry cleaning chemicals
- Oven cleaners
It’s important to limit the use or avoid products with high VOCs. You can look for “low VOCs” on the label of products such as paints and building supplies.
Buy only as much of these products as you absolutely need for your project, and dispose of any leftover or unused products safely. Make sure to use good ventilation when using products with VOCs indoors.
Allow new carpet or new building products to air out and release VOCs before installing them.
Protecting Your Immune System From Harmful Chemicals
You must assume that, in general, household and cleaning products contain harmful chemicals. Even products advertised as “natural” or “green” may contain disease-causing ingredients.
Here are a few more tips to protect yourself from chemicals that can impair immune function and overall health:
- Avoid wearing perfume and other products containing fragrance. They often contain phthalates, which can be labeled merely as “fragrance.” Use personal care products marked “fragrance-free” rather than “unscented” to avoid being tricked by the labeling.
- Avoid nail polish and hairspray. They frequently contain phthalates, toluene, and xylene.
- Avoid air fresheners completely.
- Learn how to make your own non-toxic cleaning products. You can use safe ingredients such as baking soda and vinegar.
- Always check labels for chemicals. You may see hard-to-pronounce ingredients such as parabens, oxybenzone, and sodium laureth sulfate.
- Go BPA-free. You can avoid bisphenol A by opting for fresh and frozen fruits and vegetables rather than canned foods. In general, products packaged in glass are safer. And don’t take the paper receipts from grocery stores, drug stores, and ATMs unless you really need them, because they contain BPA.
- Avoid plastics with recycle symbols #3, #6, and #7. They contain harmful chemicals that can leach toxins into your body and the environment.
- Use cast iron or stainless steel pans for cooking. As you’ve read, non-stick cookware contains toxins.
#5. Say “No” to Sugar to Strengthen Your Immune System
Among the dietary tips you will read about in this article, reducing your sugar intake is one of the best things you can do for immune health.
Soft drinks are the worst culprit when it comes to added sugar in the diets of Americans. A single can of soda contains about 11 teaspoons of sugar. Baked goods, fruit juices, dairy desserts such as ice cream, candy, breakfast cereal, beverages, and table sugar also contribute to the sugar load.
Sugar is also an added ingredient in many processed foods such as salad dressings, ketchup, cured meat, peanut butter, crackers, and many others. In fact, most processed foods contain at least some hidden sugar.
All these sources add up so that the average American eats 42 teaspoons of sugar each day!
Around 200 years ago, a typical American consumed only two pounds of sugar in an entire year. By 1970, we were up to 123 pounds of sugar per year. And today, the average American eats nearly 152 pounds of sugar per year.
Sugar Comes in Variety of Forms and Names
These are all different sweeteners providing calories, but little or no nutritional value:
- Sucrose — table sugar made from sugar cane or sugar beets
- Maltose — found in barley
- Fructose — found in fruit juice concentrate, agave, and honey
- High fructose corn syrup — made from corn starch
- Sorghum syrup — made from the sorghum plant
- Molasses — by-product of processing sugar cane into sugar
For most people, health experts agree that a small amount of sugar in the diet is not a problem. But these days, the average American consumes far too much, leading to health risks.
General Health Risks of Sugar
Most people know that eating sugar can have negative consequences on our health. Excess sugar consumption has been linked to:
- Weight gain and obesity
- Cardiovascular disease
- Liver disease
- Cognitive disorders, including Alzheimer’s
Research shows that in some people, eating sugar affects the limbic area of the brain — your reward center. This can cause feelings of craving and withdrawal.
Using brain scans, researchers at the U.S. National Institute on Drug Abuse discovered that sugar leads to brain changes similar to those produced in people addicted to drugs such as cocaine and alcohol.
Sugar and the Immune System
It’s important to realize that too much sugar consumption can impact the immune system.
A study performed by Loma Linda University examined the effects of simple carbohydrate ingestion on the capacity of neutrophils to engulf bacteria. These are white blood cells important in immunity for their capacity to fight infection. After consuming glucose, fructose, orange juice, or honey, the functioning of these immune cells was significantly reduced. The greatest effects were noted 1-2 hours after ingesting the sugars, but the effects were still noticeable after 5 hours.
Research also indicates that a so-called Western diet, high in sugar and fat, can alter the composition of the microbes in the gut, leading to a condition called dysbiosis. Since around 70% of the immune system is located in the gut, high sugar intake can contribute to immune dysfunction and increased inflammation.
The community of bacteria in the gut, called the intestinal microbiome, is essential to healthy immune responses. Dysfunction can increase susceptibility to many diseases, especially those linked to chronic inflammation. Refined sugar intake can also lead to overgrowth of opportunistic gut bacteria that can be detrimental to health.
How to Decrease Your Dietary Sugar Intake
Here are 10 tips to help you minimize your sugar consumption:
- Read food labels while shopping. This will help you find hidden sources of sugar you can avoid. In addition to the sugars noted earlier, they may be disguised as rice syrup or caramel.
- Minimize sugar sources. This includes brown sugar, honey, pancake syrup, and molasses.
- If you use sugar in coffee or tea, cut it down by half.
- Switch from drinking sodas to sparking water. Use a squeeze of lemon or lime. Or try water with cucumber and mint or some other combination (like you find at many hotel chains). Diet drinks come with their own health risks so they are not a good substitute.
- Avoid canned fruits in heavy syrup. Fresh or frozen fruit is much better.
- When baking, you can often reduce the sugar called for by 1/3. You probably won’t even notice the difference. You can also use unsweetened applesauce in recipes.
- Don’t shop when you’re hungry. Studies show that those people who do purchase more high-calorie products. Eat a healthy snack before shopping.
- Practice good sleep habits. One research study found that those subjects who did not get a good night’s sleep consumed more calories, soda, and junk food compared to those who slept well.
#6. Keep Your Gut Healthy and Happy
Now you will discover why it is so important to maintain a healthy gut. Not only for immune health, but for your general health and prevention of disease.
Did you know that during your lifetime, about 60 tons of food pass through your GI tract?
The primary function of the gut is to digest this food so that vital energy and nutrients and be extracted, then expel the remaining waste material from your body..
Your small intestine functions to take partially digested food from your stomach and absorb the most nutrients from it. Around 90% of digestion and absorption takes place in the small intestine.
Your small intestine also holds a large number of so-called ‘friendly’ bacteria, predominantly of the Lactobacillus type. You’ll see why they are so important to your health shortly.
After your small intestine finishes its job, the remaining food material then passes into the large intestine.
The large intestine performs a number of vital functions in digestion, including additional absorption of vitamins and other nutrients. It helps your body create vitamins, including some B vitamins as well as vitamin K, essential to proper blood clotting.
It also helps absorb salts and water from the remainder of the indigestible food matter to maintain proper fluid balance in your blood, among its many functions.
Your large intestine also contains plenty of friendly bacteria, predominantly of the Bifidobacteria type.
So both the small and large intestine house bacteria. In fact, your gut contains about 100 trillion bacteria weighing 2 to 3 pounds! Because of this huge quantity of living organisms, some scientists consider your gut to be an organ of sorts. They call it the “microbial organ” or “microbiome.”
So what the main benefits of these friendly bacteria?
Avoiding Digestive System Concerns
For you to remain healthy, approximately 85% of your gut bacteria should be friendly bacteria, such as Lactobacillus or Bifidobacteria. The remaining 15% are considered non-beneficial bacteria, but when their numbers remain small, they generally cause no trouble.
Unfortunately, this ratio becomes skewed for many people. Non-beneficial bacteria rise in numbers, crowding out friendly bacteria, which are also known as probiotic bacteria.
It may be surprising to realize that more than 100 million Americans suffer from digestive issues.
In fact, medical experts report that more people suffer from occasional constipation than all other health issues combined.
Millions of Americans experience bathroom frustrations such as:
- Gas or bloating
- Irregular bowel movements
- Abdominal pain or discomfort
Probiotic Bacteria Keep Your Digestive Tract Running Smoothly
Supplementing your diet with additional friendly probiotic bacteria can help keep your digestive system more balanced.
When it comes to simple constipation, probiotic bacteria can help speed up the transit time of waste material in your colon — giving you more regular and comfortable bowel movements. You may experience less gas and bloating, because probiotic bacteria help maintain your intestinal acidity at a healthy pH level.
Probiotics can also help with occasional diarrhea.
Studies confirm that probiotics lower the risk of diarrhea associated with use of antibiotic drugs. Antibiotics disrupt the normal balance of bacteria in your gut by broadly killing both friendly and pathogenic strains. Diarrhea is a frequent antibiotic side effect, but supplementing with probiotics can reduce the risk of this happening.
And here’s something you may not know…
According to the CDC, around 30% of antibiotic treatments prescribed in the outpatient setting are unnecessary.
Of course, antibiotics kill bacteria. But resistant bacteria may continue to grow and multiply. That’s a reason why overuse of antibiotics contributes to the epidemic rise in these drug-resistant bacteria.
Antibiotic resistance is particularly worrisome for older adults, who have a high rate of antibiotic use.
Recent studies, including one from Johns Hopkins, report that aging causes a reduction in population of friendly bacteria such as Bifidobacteria in the large intestine. That means that older people can experience an imbalance between beneficial and non-beneficial bacteria, which makes them vulnerable to immune issues and other concerns.
Probiotics Supports a Healthy Immune System
When you consider your immune system, your large intestine may not immediately come to mind. However, a big chunk of your immune system — around 70 to 80% — is actually be located in your gut. Scientists refer to this as GALT, or gut-associated lymphatic tissue.
Several studies, including a 2010 study out of the University of Pennsylvania School of Medicine, suggest that probiotics may help maintain immune system activity by introducing beneficial bacteria into the gut.
So supporting your immune system by supplementing with beneficial probiotic bacteria can help:
- Maintain a healthy inflammatory response by promoting anti-inflammatory cytokines and down-regulating pro-inflammatory cytokines
- Stimulating the function of regulatory immune T cells
- Minimize or preventing allergic concerns
- Control the growth and spread of pathogens
- Increase the production of antibodies
- Strengthen the intestinal barrier lining to help your body defend itself from invaders.
The Truth About Yogurt and Many Probiotic Supplements
Food manufacturers would rather you not know that store-bought yogurt products can often be a waste of your hard-earned money.
Unfortunately, most commercial yogurts come loaded with sugar and other additives. They are often heat processed or pasteurized, which destroys much of their live bacterial cultures.
What about taking probiotic supplements? Researchers warn that about 50% of probiotic products available do not contain the bacteria claimed on the label. Even those that do may not contain the best mix of bacterial strains to provide health benefits. Lower quality products may not be manufactured in an optimal way to help the probiotic bacteria survive life on the supermarket shelf, no less the harsh journey through your acid-laden gastrointestinal tract.
That’s why using a high quality probiotic supplement is the only way to guarantee you will receive the greatest health benefits.
To choose an effective probiotic, it’s important to use a formula:
- With multiple strains of researched probiotic bacteria. Different strains have different effects in the body.
- That is hypoallergic, since food sensitivities and allergies are common in those with digestive issues problems.
- Manufactured with high quality controls to make sure strains remain alive and effective through the manufacturing process.
- That has undergone testing to ensure its resistance to stomach acids and enzymes in the digestive tract.
Some additional tips to help keep your gut robust and healthy include:
- Using fermented dairy products such as kefir and organic, unsweetened yogurt, fermented teas such as kombucha, and cultured vegetables like sauerkraut and kimchi.
- Make sure to eat a lot of fiber-laden foods, such as vegetables, legumes, and fruits. Fiber not only helps prevent and relieve constipation, but helps maintain a healthy weight and reduce the risk of heart disease, diabetes, and some forms of cancer. Sadly, only about 5% of the population meets the recommendations for dietary fiber intake.
#7. Don’t Neglect Good Oral/Dental Health
You might not realize it, but your oral health and immune system go hand in hand. Your mouth represents a gateway into the body and an opportunity to defend against anything compromising our health. When oral hygiene is neglected, it can lead to dire consequences for the body. Diabetes, cardiovascular disease, some cancers, as well as gum disease and tooth decay have all been linked to poor oral health.
Unfortunately, as the National Institutes of Health points out, gum disease affects nearly 50% of American adults 30 and over and 70% of those 65 and over.
Bacteria and Other Pathogens are Comfortable in the Mouth
Nearly all problems arising from poor oral health come from bacteria, viruses, and other pathogenic organisms. Your mouth represents an ideal environment for bacteria to thrive. It’s moist, warm, and contains nutrients for bacteria to use.
When you fail to brush and floss daily, food particles remain, which allow bacteria to multiply and fester in the gums. Bacteria near the gumline form a sticky substance called plaque, which accumulates and inflames your gums. When bacterial growth and plaque multiply excessively, this can cause many complications, even the loss of bone and teeth.
Even though bacteria enter through the mouth, they don’t remain there. Bacteria can work their way into the bloodstream and respiratory system when left unchecked. Gingivitis, the most common type of gum disease caused by bacteria, is relatively mild.
However, a severe infection, called periodontitis, develops at the gumline due to increased inflammation. Gums recede from teeth, creating pockets in which pus collects. Bacteria find their way into the rest of the body through the bloodstream. This sets off an immune response, and a chain reaction leading to other health complications if not remedied early in its progression.
How Poor Oral Health Affects the Immune System
Your immune system functions to attack and kill those bacteria invading the body. Gingivitis and periodontal disease are actually inflammatory diseases caused by proliferation of bacteria. Inflammation from these bacteria signals your immune system to act
Studies suggest that an abnormal immune response also plays a role in triggering inflammation linked to periodontal disease. Immune T helper cells live in the mouth, and have been shown to have both beneficial and harmful effects. These T cells protect against a fungal infection called oral thrush, and have also been linked to gum disease.
How to Keep Your Mouth and Immune System Healthy
Optimal immune health allows your body to eliminate bacteria and prevent infection. You can help protect your immune system by maintaining good oral health.
Here are a few tips from dental experts for better oral and overall health:
- Brush your teeth daily
- Floss regularly
- Avoid smoking and consume alcohol moderately
- Get proper sleep and minimize stress
- Exercise regularly and eat a healthy diet, avoiding sugars and acidic drinks
- Probiotics have been shown by research to help prevent plaque and decrease gum inflammation
- Get regular dental exams and cleanings
- If you suffer with bleeding gums, mouth discomfort, or difficulty in chewing, see a dental professional immediately
#8. Make a Plan to Stay Active
Regular exercise improves heart health, lowers blood pressure, helps maintain optimal body weight, and decreases the risk of cancer and chronic inflammatory diseases.
But what is not so well known by the public is that exercise also helps lower the incidence of viral and bacterial infections, partly by flushing pathogens out of the lungs and airways.
Much of this can be attributed to the boost exercise gives to immune function. There is an entire field devoted to “exercise immunology.” Research reported in Frontiers in Immunology note that frequent exercise enhances immune competency.
Not only that, but by improving immune regulation, exercise can delay age-related dysfunction and improve response to vaccination.
Exercise enhances the function of antibodies, anti-inflammatory cytokines, and various immune white blood cells, which of all play critical roles in immune defense.
Studies show the most benefit from a moderately energetic lifestyle and exercise program, such as:
- Bicycling a few times a week
- Taking daily walks for 20-30 minutes
- Going to the gym or working out every other day
- Engaging in fun but active pursuits, such as playing golf regularly
Some experts claim that heavy exertion causes transient immune dysfunction, although there is conflicting evidence.
Exercising decreases stress and helps you feel healthy and energetic — for good reason. So go ahead and sign up for that exercise class or start walking every morning. Your immune system and overall health will benefit.
#9. Avoid This Trio of Unhealthy Lifestyle Choices: Smoking, Alcohol, and Fast Food
This section doesn’t need to be too long, as we all know that smoking, drinking excessively, and eating fast food are bad for us.
But it’s important to realize the effects this triad of unhealthy choices takes on our immune system.
Smoking and Immune Health
According to the CDC, cigarette smoke contains over 7,000 chemical compounds, many of which can interfere with immune function.
Smoking impacts both the innate and adaptive immune system. Innate immune cells such as macrophages and NK (natural killer) cells are functionally degraded by smoking. In the adaptive immune system, T cells and B cells are affected.
When the immune system is not working effectively due to smoking-related immune dysfunction, viral and bacterial infections can be worsened, particularly problems related to the lungs (flu and pneumonia).
The CDC warns that new research has discovered that smoking is a cause of the autoimmune disease rheumatoid arthritis (RA). In RA, the immune system attacks the joints and causes pain and swelling. Smoking also interferes with the effectiveness of certain medical treatments for RA.
There are many methods to help you quit smoking, and no one right way that works for everyone. Some involve medications and nicotine replacement therapy, and some are non-drug lifestyle modifications, such as these suggested by the Mayo Clinic:
- Avoid trigger situations where your urge for tobacco is greatest
- Chew on something crunchy and satisfying to give your mouth something to do if you experience tobacco cravings
- Physical activity can distract from cravings and lower their intensity (even a short burst of activity)
- Practice relaxation techniques such as yoga, deep-breathing exercises, or listening to calming music
- When you crave tobacco, tell yourself to wait 10 minutes and then do something else to distract yourself
If you are having difficulty quitting, ask your health provider for advice. There are also online support groups and stop-smoking programs.
Alcohol Consumption and Immune Health
According to the National Institutes of Health, around 88,000 people die from alcohol-related causes each year, making alcohol the 3rd leading preventable cause of death in the U.S.
In 2018, 26% of Americans over 18 reported binge drinking in the past month. And 6.6% admitted to engaging in heavy alcohol use in the past month.
According to the journal Alcohol Research, researchers have long observed a link between excessive alcohol consumption and weakening of immune defenses in both the innate and adaptive arms of the immune system.
Immune-related problems due to alcohol consumption include increased risk of:
- Acute respiratory stress syndromes (ARDS)
- Alcoholic liver disease (ALD)
- Certain cancers
- Slow recovery from infection and poor wound healing
Alcohol also impacts the structure and integrity of the GI tract, altering the numbers of gut bacteria and causing immune-related inflammation.
The government’s NIH notes that many options for treatment of alcohol problems exist, including behavioral treatments and counseling, mutual support groups, and medications. The first step is talking to your physician about the issue.
Fast Food and Immune Health
Almost 50% of American adults eat fast food or junk food at least once a week.
Unfortunately, eating a poor quality “junk food” diet is linked to many diseases, including:
- Heart disease and stroke
- Type 2 diabetes
- Early death
Research shows that just one junk food meal can increase inflammation body-wide.
When it comes to the effects of fast food on immune health, a recent German animal study has shown that your immune system reacts to a high fat and high calorie diet similarly to the way it reacts to bacterial infection. Researchers noted that immune cells had what they termed a “fast food sensor” that leads to the release of highly inflammatory messenger.
What’s more, this study found that unhealthy food makes the body’s defenses more aggressive over the long term. Even after switching to a healthier diet, the body’s immune defenses remained hyperactive.
With our busy lives and stressful schedules, it’s hard to eat healthy all the time. Here are 7 tips to help control cravings and stop eating so much junk food:
Shop the perimeter of the grocery store. This is where you will find “real” foods rather than highly processed items. Plus, if the food label contains unpronounceable ingredients, it’s probably not healthy.
Plan meals and snacks ahead of time. This way, you won’t be vulnerable to food smells, ads, and sudden cravings.
Make sure to eat sufficient protein. Good protein sources include fish, beans, vegetables, and nuts. Protein makes you feel full compared to when eating carbohydrates. You’ll have less room and desire for fast food.
Work on those stress levels. Cravings usually have an emotional component. So when you feel the urge to reach for a cookie, try taking some deep breaths, going for a walk, or doing a few yoga poses.
Get more sleep. As you’ve seen, sleep affects many areas of health. Research indicates that sleep deficiency leads to increased hunger and reduced ability to control snacking.
Eat the rainbow. Eating a diverse array of foods can boost your immune and overall health, as well as prevent disease. Try purple potatoes, red beets, and green kale.
Have a piece of fruit. While fruit contains sugar, it also provides nutrients and fiber. Eat some berries or watermelon instead if you’re craving a sweet treat.
#10. Eat More Vegetables and Fruits for the Antioxidant Benefits
You’ve probably heard a lot about antioxidants. However, not many people really understand what they are and how they work.
Antioxidants are molecules that fight free radicals accumulating inside your body.
Free radicals compounds cause damage when their body levels become excessive. They’ve been linked to many illnesses, including cardiovascular disease, diabetes, and even cancer.
Your body contains its own internal antioxidant defense system to keep damaging free radicals in check, called the endogenous antioxidant system. It includes antioxidants such as glutathione and superoxide dismutase (SOD). This is your first line of defense against free radicals.
Exogenous antioxidants are formed outside the body and represent a crucial back-up system. These antioxidants can be absorbed and utilized by your body cells when consumed as foods or supplements.
Some examples of exogenous antioxidants include vitamin C, vitamin E, and various flavonoid, polyphenol, and carotenoid antioxidants. These nutrients also help stimulate the body’s own production of endogenous antioxidants.
Free radicals form constantly in your body during metabolic processes. But a multitude of lifestyle, stress-related, and environmental factors promote increased free radical formation:
- Bacterial, viral, and fungal infections
- Air pollution
- Tobacco smoke
- Excessive alcohol consumption
- Toxic metals, pesticides, and chemicals
- High blood sugar
Yet, free radicals are not all bad.
Free Radicals and Immune Health
They also serve vital functions essential to your health. Immune cells need and use free radicals to defend against infections.
This immune-related protective function against external is by itself a source of free radicals. That’s because activated immune neutrophils produce their own free radicals. Moreover, the inflammatory process stimulates activation of immune phagocytes by sending out inflammatory cytokines.
That’s why your body needs to maintain balance in the number of free radicals and antioxidants.
When free radicals outnumber antioxidants, a state called oxidative stress can develop. Prolonged oxidative stress damages DNA and other vital molecules in your body. It can even cause cell death.
Oxidative stress elevates your risk of cancer and heart disease. Some researchers theorize that DNA injury from oxidative stress plays a central role in the aging process. And as you’ve seen throughout this report, chronic inflammation is linked to many diseases, including heart disease.
How Can You Get More Antioxidant Protection?
You’ll find antioxidants in certain foods, particularly fruits and vegetables. Here are some foods with a high antioxidant content:
- Red cabbage
- Purple or red grapes
You’ll notice that many antioxidant sources are quite “colorful.” That’s why health experts tell you to eat a rainbow of fruits and vegetables.
Other Tips to Reduce Free Radical Production
There are a number of simple things you can do to decrease out-of-control free radical production:
- Avoid high glycemic foods. Refined carbohydrate and sugary foods stimulate the production of free radicals.
- Exercise regularly and reduce stress.
- Don’t re-use cooking oils or fats. The cooking process oxidizes them, generating more free radicals.
- Avoid processed meats. Bacon, salami, sausages, and hot dogs contain preservative chemicals that lead to free radical production.
- Stop smoking and limit alcohol consumption.
- Maintain a normal weight. Obesity can increase the risk of oxidative stress.
- Supplement your diet with nutrients providing antioxidant protection. (These will be discussed in the next section.)
#11. Boost Immune Health With Targeted Immune Nutrients
Perhaps not surprisingly, you will find that many of the nutrients which help with immunity and inflammation are antioxidants.
Antioxidants are crucial at all ages, but particularly important for older individuals.
Middle-aged and older people need a much higher intake of antioxidant-containing foods. However, they commonly don’t consume an adequate supply of these antioxidants — or other nutrients important to immune function.
That’s why it is beneficial to supplement with specific antioxidants and other nutrients that quell inflammation and boost immunity.
Here are a few suggested antioxidants and other nutrients important to immune health:
Among its many functions, Vitamin C is a powerful antioxidant that helps reduce pro-inflammatory cytokines. It also reduces inflammation by protecting the health of blood vessels.
Stress rapidly depletes vitamin C from the body. Aging can lead to progressive vitamin C deficiency, which makes supplementation highly recommended.
Recent Vitamin D research has confirmed important interactions between vitamin D and cells from both parts of the immune system. Impaired or insufficient vitamin D levels may lead to dysregulation of immune responses.
Vitamin A is known as an anti-inflammation vitamin due to its critical role in enhancing the function of your immune system. It performs important functions in both innate and adaptive immunity. Research suggests that even a subclinical Vitamin A insufficiency can increase the risk of infection.
Beneficial probiotic bacteria such as Lactobacillus or Bifidobacteria have been scientifically shown to help with numerous health concerns, particularly conditions of the digestive and immune systems.
Around 70% of your immune system is actually located in your gut, making it crucial to maintain a healthy community of bacteria for immune defense. Aging leads to a decline in numbers of friendly gut bacteria, and an increase in the numbers of non-beneficial bacteria.
The Astragalus herb, used in Traditional Chinese Medicine, provides support for healthy immune function. It promotes immune cell development and antibody production
Astragalus also acts as an antioxidant, so it helps protect cells against damage. It has antibacterial, antiviral, and anti-inflammatory properties. In addition, studies have found that Astragalus helps promote the growth of friendly gut bacteria.
Hesperidin is a flavonoid found in high concentrations in citrus fruit such as oranges. Studies have shown that hesperidin can reduce inflammatory cytokines. It has also been shown to reduce inflammation caused by bacteria.
Vinpocetine is a naturally occurring plant extract, which acts as a powerful antioxidant, especially for some of the more destructive free radicals. It reduces inflammation, particularly in the brain by suppressing cytokines and other pro-inflammatory substances.
Quercetin is a flavonoid antioxidant found in many vegetables and fruits, particularly citrus fruits, apples, dark berries, and grapes.
Quercetin may help protect against heart disease and cancer. Quercetin can also help stabilize the cells that release histamine in the body, which creates an anti-inflammatory and antihistamine immune effect. Studies also suggest that flavonoids have anti-cancer properties.
Resveratrol is a protective antioxidant flavonoid found in the skins of grapes, berries, and peanuts.
Researchers have found that resveratrol provides powerful protecting properties, anti-inflammation being one of resveratrol’s many effects. It has been shown to suppress macrophage overactivity, reduce inflammatory cytokine production, and protect brain cells from damage by free radicals and inflammatory chemicals.
Green Tea Leaf Extract
Green tea contains high levels of anti-inflammatory compounds called catechins, especially EGCG.
Various compounds found in green tea protect against free radicals, inflammation, and even autoimmune disorders. Studies have shown that EGCG inhibits the damage caused by beta-amyloid, a compound that accumulates in the brains of people with Alzheimer’s disease.
Omega 3 oils are anti-inflammatory and omega-6 oils (found in most cooking oils) are pro-inflammatory. Omega 3 oils play an important role in immune system regulation. Unfortunately, most people get at least 10 times as many omega-6’s as are necessary, skewing the omega-3 and omega-6 balance.
Ideally, fish should give you the omega-3’s you need. However, our fish supply is quite polluted with toxins such as mercury and others. That’s why it may be good to supplement with a high-quality fish or marine oil.
This trace mineral plays a crucial role in supporting immune function and the ability to recover from infection.
Zinc deficiency reduces antibody production, reduces the body’s ability to regulate inflammation, and impairs the function of immune cells. Older adults are especially at risk for zinc inadequacy.
These compounds, found in mushrooms and yeast, can boost the response of several immune cells, including natural killer cells, lymphocytes, and neutrophils.
For example, the beta glucans found in Reishi mushroom provide regulation of the immune system with its anti-inflammatory, antibacterial, antiviral properties.
This essential micronutrient is a potent antioxidant with inflammation-reducing properties. Selenium also boosts immune system response by protecting against certain pathogens. It is believed to help prevent replication of viruses.
A selenium deficiency has been shown to decrease immune cell function and show immune response.
Berries and flowers of the elderberry plant, Sambucus nigra, are loaded with antioxidants and nutrients to help boost immune function and reduce inflammation. Some health experts recommend elderberry to help prevent and ease cold and flu symptoms.
Curcumin is actually a group of compounds derived from the turmeric plant, a yellow-orange spice and medicinal herb used over thousands of years.
Among its many benefits, several studies have found that supplementing with curcumin helps regulate immune function that has become overactive. It supports gut health by fostering the growth of friendly bacteria. Curcumin is also considered an antioxidant, and demonstrates anti-inflammatory, antiviral, and antibacterial properties.
Within this article, you have discovered dozens of simple ways you can boost your immune system naturally. Choose a few lifestyle changes and suggestions from what you read about here in this guide. This will put you well on your way to robust immune health for a lifetime.
Note: This article is not intended to provide medical advice. Any changes should be done in consultation with your own health care provider.
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