Coronavirus, SARS, Ebola, influenza! What are the potential preventive strategies being ignored by most media reports? In this two-part blog, we examine science-validated natural strategies to boost your immune system’s performance.

Body Defenses against Viral Invaders

Natural killer (NK) cells, as well as killer-T lymphocytes, are specialized immune cells that destroy viruses and cancer cells. They release chemical bullets that perforate the protein coating of viruses. Natural killer cells interfere with the replication of viruses. Although different signals actuate these two immune cells, they must be optimally functioning to protect us from super viruses.


Proper handwashing with soap and clean water is the first line of defense against super bug infection. Often wash hands for about 30 seconds. Pay attention to the areas between fingers, around thumbs, and wrists. Use paper towels to turn off the spigot. Alcohol based hand sanitizers are helpful for the coronavirus, but are not as effective as proper hand washing for the flu. As for the corona viruses, alcohol hand sanitizer is effective. Cover your mouth and nose during a cough or a sneeze with a tissue.

During viral epidemics, stop shaking hands and hugging people outside of your own family circle. Rather greet with elbow touch. This protects people from the unbeknownst spreading of viruses. Avoid touching your face with your hands if you have not washed your hands. Try to maintain a 3 foot distance between yourself and anyone who is coughing or sneezing to avoid getting virus-contaminated droplets.

Sanitize surfaces that are touched frequently with iodine spray. Lysol can also help. Do not wipe dry. Disinfectants must remain on the surfaces for a few minutes. One can also spray hands and face with iodine spray. Disinfect cell phone, key boards, and doorknobs twice a day.

Drink Pure Water!

Dehydration increases the risk for a respiratory, gut, and urinary infection. Dehydration decreases a class of antibodies in the respiratory mucosa. So, if you want to reduce your risk of flu and corona virus, drink liberal amounts of pure water.

Avoid Immune Suppressors!

Sugar is an immune suppressor and encourages inflammation that fuels chronic complications of viral infections. Alcohol suppresses natural killer cell activity.1 Chronic alcohol consumption has a double negative effect of reducing the anti-viral effect of interferon 1 while increasing inflammation.2 Interferon interferes with replication of viruses. Smoking increases one’s risk for influenza and coronavirus. Do not expose yourself to second-hand smoke. Caffeine, as well, may negatively impact lymphocytes.

Be Sure Your Vitamin D Level is Normal.

Unfortunately, Vitamin D insufficiency is common. Vitamin D is crucial to activating our immune defenses. Without sufficient intake of the vitamin, the killer T lymphocytes of the immune system will not be able to react to and fight off serious infections in the body. In other words, vitamin D is necessary to activate Killer-T cells. They will remain dormant if there is an insufficient amount of vitamin D in the blood.3 Your body produces natural antibiotic-like compounds called antimicrobial peptides in the white blood cells. Vitamin D increases the activity of these antimicrobial compounds.4,5 Dark skinned individuals and the elderly are especially prone to vitamin D deficiency. Get your level checked!

Viral-Fighting Diet!

A study found that a vegetarian diet increases NK cell activity by a factor of 2.34 compared to an omnivorous diet.6 Additionally, a well-balanced whole plant food diet combats inflammation. Meat and refined carbs are pro-inflammatory! Uncontrolled inflammation plays an important role in the spiraling complications of influenza and coronaviruses.

There are even more immune benefits to a predominately whole plant food diet. A high-fiber diet blunts harmful, excessive immune responses in the lungs. At the same time a high fiber diet boosts antiviral immunity by activating killer-T cells.7 Additionally, soluble fiber transforms the personality of immune cells. They go from being pro-inflammatory, angry cells to anti-inflammatory, healing cells that enable us to recover faster from infection.8 Bring on the apples, oats, and beans! Greens and cruciferous vegetables are especially useful for boosting immunity in the gut and the skin.9 Garlic consumption increases natural killer cell activity and helps to inhibit inflammation.

Some studies suggest that reducing fat intake to 22-25% of the total diet can improve the viral fighting protection of immune cells.10,11 A low fat diet (below 15%) can suppress immune function.

Beware of Nutritional Pitfalls.

Vegetarian diets will not enhance immunity if they are deficient in vitamin B-12, vitamin D, and omega-3 fats. Chia, flaxseed, walnuts, organic, non-GMO soybeans, and leafy greens furnish omega-3. Nutritional yeast and fortified nondairy milk often have vitamin D, but vegetarians should have their vitamin B-12 and D levels checked annually and supplement as needed. Both vitamins are essential to immune performance.

Meat substitutes generally are high in sodium and fat, but very low in fiber. Juices have minimal fiber. Definitely not a winning combination for preventive medicine! Emphasize a variety of colorful, whole plant foods for the best prevention of superbugs.

Avoid Deficiencies.

Besides B-12 and vitamin D deficiencies, other nutrient deficiencies can work havoc on the immune system. While it is true, a short fast improves natural killer cell activity, not eating enough protein decreases antibody production. Adequate amounts of vitamins C, D, A, and B-12 are essential for optimal immune efficiency. As we age, the lymphocytes become less efficient. Wise calorie-restriction, vitamin E from nuts and seeds, and folic acid from greens and oranges slow down this aging of the specific immune system.

Include these Trace Elements!

Nutrients and phytochemicals work in synergy to enhance immunity. Therefore, we encourage eating a healthful diet instead of just using vitamin and mineral supplements as insurance. Selenium and zinc deserve especially attention for immune health. Selenium also helps NK cells to proliferate and increases their virus-fighting activity, too. Brazil nuts, cashews, oats, brown rice, lentils, and spinach provide good amounts of this trace mineral. One Brazil nut has more than the daily requirement for selenium!

Zinc is a trace mineral that exerts antioxidant activity and is essential for all immune cells. Zinc deficiency reduces the efficiency of T-lymphocytes. While it is important to have sufficient zinc in your diet, too much zinc can actually inhibit the function of the immune system. How much do you need? About 11 to 15 milligrams a day for an adult. Taking more than 25 mgs. a day can have adverse effects. Plant foods are not high in zinc. A half a cup of tofu provides 2 mgs, one cup of oatmeal has 2.3mgs, one-half cup of most legumes and one-fourth cup of nuts contain approximately 1 mg. of zinc. Vegetarians can be at risk for zinc deficiency if their diet is not carefully balanced to include zinc.

Rev up the Viral Killers.

Moderate exercise increases antibody production. It improves T-lymphocyte function in the elderly, and slows down the aging of the immune system. Regular exercise improves resting natural killer activity in the elderly. Aerobic exercise increases the number and efficiency of the natural killer cells. Following strenuous, exhaustive exercise though, and the number of natural killers is decreased, and their activity is depressed for several days.12

Contrast Showers!

If you do not have a neurological or circulatory disorder, severe anemia, or a blood vessel disorder, contrast showers are an excellent way to propel dormant immune cells into active service. Do an alternating hot and cold shower, as tolerated, in a warm bathroom: hot for 1 ½ minutes and cold for 30 seconds; do three exchanges. Be sure to make the second and third changes progressively hotter. Finish with cold. Hot and cold showers boost the number of circulating white blood cells. Perform this treatment twice a day, ideally. And one time a day is much better than none! Rest afterwards to enhance the effect.


Partial sleep deprivation reduces natural killer cell activity per number of natural killer cells. Even a modest sleep deprivation for part of the night can reduce the killing ability of the natural killer cells by almost 30%.13 Just one night of short sleep produces an inflammatory response that is detrimental!14

Think Positively.

Scientific studies confirm these observations. They show that major depression, for example, reduces NK cells’ effectiveness. A persistent negative outlook erodes both the ability of the NK cells and killer T-lymphocytes to destroy viruses and cancer cells. The emotions and reactive thinking common in depression—helplessness, loneliness, hopelessness, lack of social support, and unhealthy suppression of these feelings—not only depress the mind but the immune system as well.15

Stress reduces the ability of NK cells to make interferon, a chemical that substantially decreases viral replication. However, problem-solving techniques and coping skills improve NK activity in stressed persons. If the individual possesses high emotional stability and low anxiety, stress actually promotes NK cell activity. On the other hand, the same stress can result in a significant decline in NK cells if the individual possesses high anxiety and low emotional stability.16Confidence, openness, social support, effective coping skills, self-discipline, trust, faith, and a will to survive improve NK cells’ efficiency.17


Although we should be concerned about potential emerging viral pandemics, we need to take a proactive stance rather than go into a panicked frenzy. Proactive is the healthier, preventative approach!

© 2020, Wildwood Sanitarium. All rights reserved.

Disclaimer: The information in this article is educational and general in nature. Neither Wildwood Lifestyle Center, its entities, nor author intend this article as a substitute for medical diagnosis, counsel, or treatment by a qualified health professional.

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