Natural Supplements to Support the Immune System

What Does the Latest Medical Research Show?

Vitamins to Boost Your Immune System

Verywell / Ellen Lindner

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The immune system involves many different cells, tissues, and organs working together to protect the body from foreign bodies, infections, and other diseases. However, the immune system can only function at its best when sufficient nutrients are available.

There are many different types of natural supplements and herbal supplements said to help the body strengthen its ability to fight off disease. Dietary supplements involve a concentrated form of various types of nutrients and are aimed at increasing the level of nutrients the body absorbs. They can include vitamins, minerals, herbal supplements, amino acids, and enzymes.

Vitamins and Minerals

Four vitamins that are important when it comes to supporting the immune system are vitamin C, vitamin D, vitamin E, and the B complex vitamins.

Vitamin C

A lack of vitamin C in the diet is thought to make a person more prone to illness. Vitamin C is a powerful antioxidant, but, according to Oregon State University, there is not enough clinical research evidence to show that vitamin C can boost the immune system in the prevention of conditions such as the common cold. However, the study found that during extremely stressful situations (such as for those running a marathon) vitamin C supplementation resulted in a lower incidence of upper respiratory infections.

Caution should be used when taking daily vitamin C supplements. The body can only absorb so much vitamin C at one time. High dosages of vitamin C taken by mouth can result in side effects such as diarrhea and upset stomach, as well as potentially interfering with normal glucometer (instruments commonly used to measure blood sugar in those who are diabetic) blood sugar readings.

Unless a doctor, knowledgeable in the safe use of herbs and supplements gives a recommendation (such as when a person is vitamin C deficient), it may be better to get your daily levels of vitamin C from food sources such as kiwi fruit, citrus fruit, strawberries, red bell peppers, and more.

Note, if vitamin C supplements are taken, it is best to space it out during the day, instead of taking the entire daily dose all at once.

Vitamin B

Human studies have discovered that vitamin B6 levels impact the immune response. In fact, the body requires B vitamins to make immune cells. There are several members of the B complex vitamins required to promote disease prevention by boosting the immune system, including pyroxidine (B6) thiamine (B1), riboflavin (B2) and more. These B vitaimins are essential for maintaining a healthy immune systems.

Foods should be the primary source of B vitamins but various factors could lead to a deficiency in vitamin B; these include lack of a varied diet (including food sources rich in B vitamins), taking certain medications and more. Unless a person has a vitamin B deficiency, supplements may not be necessary. Foods such as green vegetables, beef liver, tuna, salmon, fortified cereals, onion, chicken and cold water sources of fish, and chickpeas are great sources of vitamin B6.

Vitamin D

Vitamin D deficiency is associated with an increase in susceptibility to infection. In fact, a 2012 study looked at multiple studies that reported lower levels of vitamin D were linked with an increase in infection (such as respiratory tract infections). 

A double-blind placebo study (the gold standard of medical research studies) found that a therapeutic dose of vitamin D resulted in a 42% lower incidence of influenza infections. 

According to a 2013 study published by the journal DermatoEndocrinol, vitamin D deficiency should be addressed by:

  1. Eating foods that naturally contain vitamin D (such as vitamin D fortified dairy products, fatty fish [like tuna and salmon], egg yolks and beef liver)
  2. Getting sensible exposure to the sun (sunlight promotes vitamin D synthesis in the body).
  3. Taking vitamin D supplements. 

Just as with other vitamin supplements, caution should be used before taking vitamin D. When taken in high doses, vitamin D can elevates calcium levels in the blood. This increase in calcium can be dangerous and result in serious side effects. Also, many medications can interfere with vitamin D and calcium levels. Vitamin D should only be taken if approved by a healthcare professional.

Note, be sure to consult with a healthcare provider who is knowledgeable about natural supplements before taking vitamin D (particularly for those with a medical condition or those taking medications).

Vitamin E

Although there are some schools of thought that promote the use of vitamin E supplements; but this supplement has not been found to support the immune system in fighting influenza. In addition, vitamin E supplementation can be harmful in certain situations (such as for smokers).

By no means does this doesn't mean that vitamin E is not good for you. Rather, it indicates that food sources are best. In fact, according to Harvard Health, "It’s especially important to avoid taking vitamin E supplements. Not only is there little clinical research showing that vitamin E supplements benefit your health, they may be harmful in some situations."

Antioxidants (such as those in vitamin E) have been found to play a vital role in a healthy immune system. Vitamin E, has been found to inhibit viral replication (the formation of viruses after infection in the host). Getting enough vitamin E in the diet is the best way to ensure adequate supplies of this powerful antioxidant. Foods high in vitamin E include nuts, seeds, avocados, grapeseed oil, and spinach.

Trace Elements

Trace elements are minerals that are present in very small amounts in human tissue, including:

Adequate amounts of trace elements are required for the efficient functioning of the immune system. During a bought of flu, it's common that trace element intake is insufficient. This can be due to a lack of appetite or due to symptoms such as vomiting. During these instances, (and other situations) your healthcare provider may recommend a trace element supplement.

Trace elements are toxic when taken in large enough doses for a long period of time. Therefore, it’s important to consult with your healthcare provider before taking zinc, selenium, or other trace elements.


Probiotics are defined as live microorganisms that offer health benefits when consumed in adequate amounts as part of food. Probiotics, sometimes referred to as “good bacteria,” live in the gut, promoting gut health. There is a very strong link to a person’s gut health and the immune system. In fact, a 2011 study published in the journal Current Opinions in Gastroenterology reported that several compounds derived from probiotics facilitate immunoregulatory effects—in other words, they help the body regulate the immune system.

Specific probiotics, including Lactobacillus, Bifidobacterium, and Saccharomyces, have been extensively studied. When combined, these probiotics were found to promote the generation of T cells. However, their ability to help the immune system regulate itself has not been evaluated.

In general, you should consider selecting a probiotic that has:

  • at least a billion colony forming units
  • contains Lactobacillus, Bifidobacterium, or Saccharomyces boulardii (three of the most commonly studied probiotics).

Herbal Supplements


Although there are many herbal supplements, Echinacea is the most popular one said to boost the immune system. This medicinal plant contains phytochemicals, which are compounds with important biological activity. Echinacea has been used for many years in traditional medicine. Polyphenols produced by this herbal plant comprise the most abundant antioxidants in the human diet.

Studies about Echinacea's health benefits are mixed, claiming that Echinacea is both ineffective and effective at boosting the immune system. Much of the inconsistency in the study data results from a lack of rigorous testing.


The primary consideration to keep in mind when it comes to taking any type of natural supplement to boost the immune system is that supplements can interact adversely with prescription and over-the-counter drugs, as well as with other natural or herbal supplements. They can also compound certain health problems.

In fact, some supplements that seem very harmless, such as vitamins, should not be used in specific circumstances. One example is vitamin C supplementation, which should be avoided in those with kidney stones.

Safe and effective use of supplements should be guided by a healthcare provider who is knowledgeable in the appropriate use of herbs and supplements.

Tips for Boosting the Immune System Naturally

In general, eating a variety of fresh—and colorful—foods should be your first line of defense in protecting your immune system and getting proper nutrients. In addition to fruits and vegetables, be sure to eat nutrient-rich foods like nuts, legumes, yogurt, and lean protein sources.

Drinking plenty of water is also important. Staying hydrated can help boost your immune system because water enables the body to produce lymph fluid. The lymphatic system carries white blood cells—which recognize and destroy germs—to various locations in the body.

Building a strong immune system happens over time. Taking a huge dose of natural supplements to boost the immune system can be compared to eating five apples in the morning and expecting it to fight off this season's flu virus. Healthy eating habits require a wide and consistent variety of nutrients.

A Word from Verywell

Natural supplements such as vitamins and other nutrients should be used to fill in the gaps in your diet, not as a primary source of nutrients. Nutrients from whole foods are more readily available to be used by your body; but various factors can deplete a person's nutrients. One such factor is medications, see this handy drug induced nutrient depletion chart to see if a medication you are taking could cause a specific nutrient depletion. If you identify a drug you are on, be sure to consult with a healthcare provider, who is knowledgeable in the use of natural supplements, regarding the best dosage, best time to take the supplement, or whether any other medications you are taking may interact with the vitamin (or other natural supplement).

17 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. The FDA Food & Drug Administration. What you need to know about dietary supplements.

  2. Oregaon State University. Linus Pauling Institute. Micronutrient INformation Center. Vitamin C.

  3. Office of Dietary Supplements. Vitamin C.

  4. Qian B, Shen S, Zhang J, Jing P. Effects of vitamin B6 deficiency on the composition and functional potential of T cell populations. J Immunol Res. 2017;2017:2197975. doi:10.1155/2017/2197975

  5. Mikkelsen, Kathleen & Stojanovska, Lily & Prakash, Monica & Apostolopoulos, Vasso. (2016). The effects of vitamin B on the immune/cytokine network and their involvement in depression. Maturitas. 96. doi:10.1016/j.maturitas.2016.11.012.

  6. Office of Dietary Supplements. Vitamin B6.

  7. Aranow, C. Vitamin D and the Immune System. J Investig Med. 2011 Aug; 59(6): 881–886.

  8. Wacker M, Holick MF. Sunlight and Vitamin D: A global perspective for health. Dermatoendocrinol. 2013;5(1):51-108. doi:10.4161/derm.24494

  9. Mileva, M. and Galabov, A. Vitamin E and influenza virus infection. IntechOpen. doi:10.5772/intechopen.80954

  10. Harvard Health Publishing. Harvard Medical School. How to boost your immune system.

  11. Office of Dietary Supplements. Vitamin E.

  12. Maggini S, Wintergerst ES, Beveridge S, Hornig DH. Selected vitamins and trace elements support immune function by strengthening epithelial barriers and cellular and humoral immune responses. Br J Nutr. 2007;98 Suppl 1:S29-35. doi:10.1017/S0007114507832971

  13. Yan F, Polk DB. Probiotics and immune health. Curr Opin Gastroenterol. 2011;27(6):496-501. doi:10.1097/MOG.0b013e32834baa4d

  14. Mohr AE, Basile AJ, Crawford MS, Sweazea KL, Carpenter KC. Probiotic supplementation has a limited effect on circulating immune and inflammatory markers in healthy adults: A systematic review of randomized controlled trials. J Acad Nutr Diet. 2020;120(4):548-564. doi:10.1016/j.jand.2019.08.018

  15. Catanzaro M, Corsini E, Rosini M, Racchi M, Lanni C. Immunomodulators inspired by nature: A review on curcumin and Echinacea. Molecules. 2018;23(11). doi:10.3390/molecules23112778

  16. Harvard Health Publication. The kidney stone diet: Not as restrictive as you may think.

  17. Federal Occupational Health. Fruits and veggies—more matters.

Additional Reading

By Sherry Christiansen
Sherry Christiansen is a medical writer with a healthcare background. She has worked in the hospital setting and collaborated on Alzheimer's research.