Immune-Boosting Supplements in a Nutshell

Your body can get some help fighting off potential viral infection from these supplements

Immune-Boosting Supplements in a Nutshell
(Jiang Dongmei/Shutterstock)

It seems it's more important than ever to be sure we do all we can to boost our immune system and ward off infection. While it's true that a healthy immune system relies on a variety of factors, including nutrition, exercise, stress management, sleep, environmental pollutants, and genetics, we all can also turn to some of the gifts of nature to provide extra support.

The following supplements are a sample of some of the immune-boosting options that are available. Each one has its own special qualities, and some may be better suited for your needs than others. Here's a review.


Astralagus is an adaptogen, which means it is an herb with an ability to fight stress, regulate the nervous system, improve mood, and return the body to balance. Because stress is an important factor in compromising the immune system, the use of astralagus can be instrumental in supporting immune function. Many studies have explored the effect of astragalus on the immune system, including one in which the herb helped suppress inflammation.
When taking an astralagus supplement, follow the directions from the manufacturer or consult a knowledgeable health care professional.

Colloidal Silver

Many people are confused about what colloidal silver is and how to use it. The term refers to various forms of silver available as dietary supplements. Basically, colloidal silver is a suspension that contains silver particles as well as silver ions. The particle sizes range from 10–1,000 nanometers (nm), and the smaller the particles, the more bioactive the supplement.
Colloidal silver is best known as an antimicrobial agent. According to Dr. Joseph Mercola, colloidal silver is active against certain bacteria, such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and S. epidermidis. Research also shows that the supplement may help eliminate a limited number of fungi as well.
Another way colloidal silver may benefit the immune system is as a booster for antibiotics. The use of the supplement along with amoxicillin, clindamycin, erythromycin, or vancomycin may enhance the powers of these drugs. Use colloidal silver as recommended by a knowledgeable health care provider.


Nature is pretty smart, providing a wealth of vitamins, minerals, enzymes, antibodies, and other essential ingredients to newborn mammals immediately after they are born. Colostrum is the source of this treasure, which is expressed by mothers during the first day of days following birth. This translucent substance also introduces critical beneficial bacteria, namely Lactobacillus acidophilus and Bifidobacterium, to the immune and digestive systems.
Adults can benefit from colostrum too. Colostrum supplements, which are made from bovine colostrum, can help balance our delicate microbiome and protect our gut lining from invading toxins and disease-causing microbes, such as Escherichia coli, Helicobacter pylori, Campylobacter jejuni, and others.
Colostrum supplements are available as powder, chewable, and capsules. It's best to take colostrum on an empty stomach 30 minutes before or two hours after eating. A standard dose is 1–3 grams daily, but higher doses are suggested for those experiencing significant stress.


Echinacea is a flower that has both antibacterial and antiviral properties. Nature provides us with nine species of Echinacea, but only three of them are used in natural remedies: Echinacea angustifolia, E. pallida, and E. purpurea, so check your supplement labels.
All three contain phenols, which are potent antioxidants. Only E. angustifolia and E. purpurea also have alkylamides or alkamides, which support immune system functioning. Caffeic acid is also present, and this compound has antioxidant and anti-inflammatory properties.
The infection-fighting powers of Echinacea have been demonstrated in various studies. One meta-analysis that included nearly 2,500 participants showed that the herb reduces the risk of recurrent respiratory infections, especially in vulnerable individuals.
Currently, there is no standard dose of Echinacea. For tinctures, a suggested dose is 0.75–1.5 milliliters daily. If you drink the tea, 6–8 ounces four times daily is one recommendation. Consult a knowledgeable health care provider for additional suggestions.


Did you know goldenseal is a member of the buttercup family? Goldenseal (Hydrastic canadensis) is often used along with Echinacea because the two herbs complement and increase the potency of the other. In fact, the main benefit of this mixture of herbs is to enhance the immune system. Goldenseal and Echinacea together is a favorite combination herbal remedy for cold, flu, and other infections, including those that affect the sinuses, throat, urinary tract, vagina, intestinal tract, and mouth.
Goldenseal contains berberine, a compound that been shown to kill bacteria, yeast, and parasites. Berberine may also stimulate white blood cells to make them more effective at fighting infections. According to the authors of a study appearing in International Immunopharmacology, for example, berberine may be useful for the treatment of infections with influenza A.
Take goldenseal and Echinacea as directed on the package or discuss your options with a knowledgeable health care professional.


Medicinal mushrooms are valued around the world for their healing properties. Maitake, reishi, shiitake, Chaga, lion's mane, and others have demonstrated abilities to support and enhance the immune system. One of the immune system boosters in these and other mushrooms is glucan, a polysaccharide. Another immune system supporter is superoxide dismutase, a potent antioxidant enzyme found in abundance in Chaga mushrooms. These mushrooms, in particular, have been found to have at least seven other antioxidants.
Shiitake and maitake also can stimulate an immune response. In a 2014 study, researchers found that a combination of the two mushrooms resulted in the strongest response followed by maitake alone.
Medicinal mushroom supplements should be taken according to the manufacturer's directions or the advice of a knowledgeable health care professional.

Oil of Oregano

This aromatic oil is derived from the oregano plant (Origanum vulgare) and contains potent compounds with healing qualities. Three of them are carvacrol, which can stop bacterial growth, including Staphylococcus aureus and S. epidermidis; rosmarinic acid, a potent antioxidant; and thymol, a natural antifungal, effective against Candida albicans, C. tropicalis, and C. krusei strains.
Lab and animal studies suggest oregano oil may reduce inflammation and swelling. Oil of oregano can be used topically or orally (drops, capsules). Use the oil on your skin to fight fungal infections or swollen glands. If you take it orally, use once or twice a day every other day to help prevent cold or flu. If you're already fighting a cold, a suggestion is to take it every day until symptoms disappear.

Olive Leaf Extract

Extracts of olive leaf contain a unique molecule called oleuropein, which is found not only in the olive fruit but in the leaves as well. Oleuropein is a potent antioxidant and anti-inflammatory ingredient that may have cancer-fighting abilities as well, at least according to some research. For example, olive leaf extract reduced inflammation and inflammatory markers in animal studies, including those involving colitis and Crohn's disease.
In a 2018 study in the Journal of Medicinal Food, the authors noted that olive leaves are a rich source of polyphenolic compounds shown to have anti-inflammatory, antioxidant, and antimicrobial abilities. The herb's antibacterial is limited to gram-positive bacteria.
The standard dose of olive leaf extract is 500–1,000 mg daily.


Let's hear it for beneficial bacteria, aka probiotics, which help keep our microbiome in balance, our immune system running smoothly, and our digestive track purring. Probiotics are so important for all these reasons because about 80 percent of your immune system is found in your gut. If you keep your gut happy by providing it with good bacteria species, especially those from Lactobacillus and Bifidobacterium, your immune and digestive systems can be happy as well.

Probiotics are also helpful for maximizing the nutrients you derive from your food. If you lack sufficient probiotics to aid with the absorption of nutrients, there's a chance you will experience nutritional deficiencies and as a result, problems with your immune function.

Generally, you want to take a probiotic supplement that provides at least 10 billion CFUs (colony forming units) daily for maintenance, and a higher dose if you are managing a health challenge. Take probiotic supplements 30 minutes before you have a meal for the best results.

Vitamin C

Many of us begin to pop vitamin C supplements when we feel a cold or the flu coming on, but it's really important to always keep our levels of the vitamin up in the body. Why? This nutrient, also known as L-ascorbic acid, dissolves quickly in the body and is not stored. Therefore, it's essential to consume it on a regular basis in food and supplements when needed.

When it comes to the immune system, vitamin C plays several critical roles. Perhaps the most important is its antioxidant properties, which means it helps eliminate disease-causing, cell-damaging free radical molecules. Vitamin C also reduces inflammation and assists with wound healing.

The Recommended Daily Allowance of vitamin C for adult men and women is 90 milligrams (mg) and 75 mg, respectively, with an upper limit of 2,000 mg daily. Too much of the vitamin can cause nausea, diarrhea, headache, insomnia, abdominal cramps, and vomiting, so avoid taking too much in supplement form. High vitamin C intake from food does not usually cause a problem and is superior to vitamin tablets.

Vitamin D

The story behind the sunshine vitamin and hormone is that the majority of people have insufficient levels or are deficient in this essential nutrient. People who have a vitamin D deficiency, for example, and who take a supplement, may develop fewer cases of flu or colds. One review showed a 12 percent reduced risk for respiratory infections after people took vitamin D supplements. The best way to get your vitamin D, however, is to just get some sun on your skin.
According to the Journal of Investigative Medicine, vitamin D has an ability to modulate immune responses, and a deficiency in the nutrient is associated with an increased risk of autoimmune conditions and higher susceptibility to infection. Before taking a vitamin D supplement, ask your health care provider to test your levels. Then you and your doctor can determine the best dose for your needs.


Zinc has become almost synonymous with helping manage the common cold. Use of zinc lozenges may reduce how long you have a cold by a day or two if you take them within 24 hours of experiencing symptoms. Zinc also may reduce upper respiratory infections in kids.
Yet this mineral can also help with other immune system attacks. That's because zinc, which is found in cells throughout the body, helps ward off viruses and bacteria wherever they are. The RDA for zinc is 8 mg daily for women and 11 mg for men. If you are already getting enough zinc from your diet, experts are not certain that taking more from supplements is beneficial.
Lisa Roth Collins is a registered holistic nutritionist and the marketing manager at, which first published this article.