Additional menu

Ranking the best immune system supplements of 2021

Written by John Davis

Last updated: May 24, 2021

Immune system supplements are designed to help your body’s immune system in its fight against viruses and bacteria.

It’s essential to strengthen your body’s immunity where you can to ensure you’re less susceptible to illnesses, especially in times of increased stress and pandemics.

Luckily, there are specific vitamins and minerals you can supplement to give your body the support it needs.

Below we’ll review the best supplements for immune system boosting so you can protect yourself and your loved ones in times of need.


1. Legion Athletics Immune

Check lowest price

Immune by Legion Athletics enhances your immune system, and attacks pathogens at their source, stopping them before they have a chance to infect you. All ingredients are 100% natural and backed by peer-reviewed scientific research.

There are no fillers, additives, or preservatives included in this product either. All this adds up to make Legion Athletics Immune our top recommendation.

2. Genius Mushrooms

Check price at Amazon

Genius Mushrooms supplement enhances mental clarity, immune function, and energy through the use of medicinal mushrooms. It includes Reishi mushroom extract, which is a strong immunity booster that also provides liver support.

It also includes Lions Mane and Cordyceps Sinensis, which provide brain-boosting and energy enhancements. These veggie pills are a great all-around immunity-boosting choice.

3. Zhou Nutrition Elder-Mune

Check price at Amazon

Zhou Nutrition has combined the forces of elderberry extract, vitamin C, and zinc to create a potent 3-in-1 immunity boosting supplement.

Containing one of the highest amounts of Sambucus elderberry extract, this product is definitely worth considering.

4. Quantum Health

Check price at Amazon

Quantum’s supplement formula contains vitamin C, echinacea, licorice, propolis, and odorless garlic to make for a powerful immunity-boosting tablet.

This supplement also contains no GMO’s, fillers, additives, or preservatives, making it a solid choice if purity is important to you.

5. Dakota Immune Defense

Check price at Amazon

Dakota Immune Defense combines traditional herbal remedies like elderberry, ginger, and turmeric with micronutrient-focused ingredients to boost immunity, like vitamin C, zinc, and vitamin D. For a robust and well-rounded immune supplement that focuses on general immune support instead of just one or two key ingredients, it’s a solid choice.

6. Zarbee’s Elderberry

Check price at Amazon

Zarbee’s elderberry gummies are made with fruit pectin instead of animal gelatin, making them vegetarian-friendly.

The combination of vitamins A, C, D, E, and zinc, as well as elderberry extract, provide your body with immune support and antioxidants with great flavor.

7. NatureWise Vitamin D

Check price at Amazon

These soft gels provide a high dose of Vitamin D, an imperative vitamin for immunity, without needing to expose yourself to harmful UVB rays. NatureWise vitamin D3 soft gels are also offered in certified organic oil for better absorption in the body.

These Vitamin D3 immune support and bone health supplements are gluten-free and non-GMO.

8. HRx Immune Support Formula

Check price at Amazon

C&S Nutrition’s HRx immune support formula is an all-natural maximum strength immunity booster that helps speed recovery and prevents immunity down-regulation.

This supplement contains ingredients such as Vitamin C, zinc, oregano oil, and red marine algae, which have all been proven immunity boosters. It’s also manufactured in a GMP compliant and FDA approved facility.

9. Nature’s Way SystemWell Ultimate Immunity Multi-System Defense

Check price at Amazon

Tackling the five essential aspects of immunity, Nature’s Way Systemwell works with your body to increase your immunity at multiple levels.

This supplement contains all the usual immunity-boosting components like vitamin C and D but has the added benefit of having blends specific to each of the five immunity systems. It contains no sugar, salt, yeast, soy, dairy products, or any artificial flavors or preservatives.

10. New Chapter Reishi Mushroom

Check price at Amazon

New Chapter’s medicinal mushroom helps regulate the body’s natural immune response using whole-life cycle organic Reishi mushrooms.

It’s completely pure, and is free of GMOs, and gluten. This supplement is also kosher, and 100% vegan.

Category winners

Best immune supplement overall: Legion Athletics Immune

Legion Athletics Immune uses a potent dose of garlic, ginseng, geranium, and other powerful immune boosters. It’s a strong, well-rounded strategy to combat a sore throat and other cold symptoms. 

Best immune supplement with zinc: Zhou Elder-Mune Gummies

Zhou Nutrition blends the traditional immunity boosting properties of elderberry with a solid dosage of both zinc and vitamin C. These are combined in a tasty gummy that makes it easy to deliver zinc directly to a sore throat.

Best immune supplement with vitamin C: Legion Athletics Immune

Legion Athletics Immune provides a prodigious 1500 mg of vitamin C alongside herbal extracts from garlic, ginseng, and geranium, plus the known cold-combatting effects of zinc. The synergistic effects of the vitamin C alongside the other ingredients make it a solid supplement that goes beyond merely providing vitamin C.

Best natural immune supplement: Genius Mushrooms

Genius Mushrooms uses the natural immunity-boosting properties in medicinal mushrooms like cordyceps, reishi, and lion’s mane. This powerful blend is our pick for an all-natural immune booster.

Best immune supplement for athletes: NatureWise Vitamin D

Athletes looking for a straightforward supplement meant to boost immunity need not look further than NatureWise Vitamin D. It’s high-dosage, ultra-pure, and free of extraneous herbal or supplemental compounds that might interact with other supplements you’re taking.

Best immune supplement gummies: Zhou Elder-Mune Gummies

If you’re not big on swallowing capsules, or if you have a sore throat and want a more direct route from supplement to irritated area, Zhou Elder-Mune Gummies are the way to go. The easily-chewable and tasty gummies deliver a high dose of vitamin C, zinc, and elderberry extract, without much in the way of extraneous ingredients.

Who should buy immune supplements? 

Immune system supplements are great for any individual looking to boost their immune system to protect themselves from harmful bacteria and viruses. They are also great for people that are especially susceptible, like the elderly and immunocompromised.

Moreover, if you’re suffering from a certain vitamin or mineral deficiency (such as a zinc deficiency) resulting in a weak immune system, supplementing is very beneficial.

Special populations, such as pregnant and breastfeeding women should consult with a doctor before taking immunity-boosting supplements as some of the ingredients may have negative side effects on the baby.

How we ranked

When ranking the best immune system supplements, we first looked at the ingredients. We only wanted products with scientifically backed ingredients such as zinc, vitamin C, vitamin D, and elderberry. Products that contained combinations of these proven ingredients, like Immune by Legion Athletics, ranked exceptionally well. Supplements that included other immunity bossing ingredients like mushrooms were also rewarded. 

Leading off of this, we wanted to ensure all products used proper clinically effective dosages so that every serving was maximized. We also rewarded companies like Nature Wise, which included some fat in the form of organic olive oil as this helped improve the bioavailability of certain immune-boosting ingredients. 

Next, we looked a quality. All products on our list, like HRx and Zarbee’s, are made in GMP-certified facilities and contain no additives, fillers, or preservatives. 


Immune system supplements may help shorten the duration of colds and fight influenza. Elderberry is known as a natural remedy for the flu and can help reduce the duration of it. This is because it contains polyphenols, which help activate the body’s immune system to fight off colds.

One 2016 study showed that people who were consumed elderberry extract recovered faster from a cold than people who did not consume it (1).

Another study looking at influenza showed that people who took four tablespoons per day of elderberry syrup got over the flu faster than those who received a placebo (2).

Garlic is a potent immune system supplement that has been shown to reduce the likelihood of common colds by up to 30% (3).

Zinc is another powerful immune system supplement that has been shown to protect against respiratory tract infections before and after people get sick (4).

A 2019 study showed that patients suffering from acute lower respiratory tract infections who consumed 30 mg of zinc daily reduced the duration of the hospital stay by an average of 2 days (5).

Immune system supplements can improve natural killer cells and reduce inflammation. It’s well known that medicinal mushrooms may help improve the activity of macrophages, which help to kill bacteria that may be harmful to the body.

A 2014 study also showed that mushrooms might also prepare the body’s immune system, to help it deal with foreign invaders better (6).

Amrit is another immune-boosting ingredient that has been used for centuries in Ayurvedic medicine. A 2007 study showed that it contains ingredients that help improve the power of macrophages to kill off bacteria more effectively.

In the 18-month double-blind, randomized controlled study, it was found that diabetic patients with foot ulcers on Amrit, showed significantly better wound healing. Improved phagocytosis showed beneficial effects of immunomodulation (7). 

Immune system supplements can improve immune cell signaling. Zinc is one of the best ingredients out there for immune support, based on the evidence supporting the claims around this nutrient (8).

Zinc has a crucial role in the development of your immune cells and cell function and signaling. Without sufficient zinc in your body, the immune response time decreases, making you more prone to get ill or get injured.

Immune system supplements can protect your body from free radicals. Medicinal mushrooms, like Chaga and Reishi, are immune system boosting ingredients that are full of antioxidants to protect against free radical damage. One 2010 study showed that Chaga could help reduce systemic stress due to its antioxidant capabilities (9).

Cordyceps is another mushroom that’s been shown to improve immune function in animal studies (10). It’s speculated that the immune system boosting properties are due to the polysaccharides contained inside this type of mushroom (11).

Vitamin C serves as an antioxidant in your body, protecting your cells from harm caused by so-called free radicals (12). In other words, it supports your immune defense and safeguards your body from infections (13).

Aside from its directly protective function, vitamin C is also essential in cleansing your immune system by helping it flush out old cells to replace it with new cells.

As with zinc, there are tons of studies out there evidencing the role of vitamin C in your immune response. This makes it not only one of the best, but one of the most reliable and scientifically proven supplements to support your immune system.

Ginseng is another powerful immune system supplement that has antioxidant properties and helps to decrease inflammation while improving immune function.

Immune system supplements can improve immune response. Studies show that people with a vitamin D deficiency may improve immune response by supplementing with this vitamin (14). Vitamin D deficiency is also linked to an increased risk of infections, in particular respiratory tract infections. However, this is not the only role of vitamin D in your body. 

This vitamin, which also acts as a hormone, supports strong muscles and healthy bones as well. It’s particularly popular in supplements because it’s sometimes difficult for people to get enough vitamin D outside of wintertime, as our main source of vitamin D is sunlight. 

A 2017 study published in the Journal of American Geriatrics Society set out to determine the efficacy and safety of high-dose vitamin D supplementation for the prevention of acute respiratory infection (ARI) in older long-term care residents.

For 12 months, researchers gave 107 older men and women varying doses of vitamin D. After the study, it was concluded that the group receiving the highest dose of vitamin D experienced 40 percent fewer respiratory infections than those who received the standard dose. However, they did also have an increase in falls, which was a little bit worrisome (15).

Another 2017 meta-analysis involving 11,000 participants and 25 randomized controlled trials showed that vitamin D was good for protecting against acute respiratory tract infections, but showed the most promise in people who were vitamin D deficient (16).

Ginseng is another immune system supplement that has been proven to improve the immune response (17). Red ginseng specifically improves the health of the epithelial cells within your lungs, which are the most susceptible to damage during a flu virus invasion. More human research is needed to confirm this since most studies show the beneficial effects in mice.

Garlic is another powerful immune-supporting supplement that’s’ been used for centuries in traditional medicine to treat colds. The reason it is so effective is that it contains an antioxidant known as S-allylcysteine, which can provide powerful pathogen fighting nutrients, like sulfur (18).

One 12 week study showed that a sulfur compound in garlic, called allicin helps to lower blood pressure, improve cholesterol levels, and increase glutathione production (19).

Immune system supplements may improve the effectiveness of vaccinations. A 1996 study published in Drugs Under Experimental and Clinical Research showed that ginseng might be able to enhance the effect of vaccinations against the flu (17).

More research is need thought to confirm these findings.

Immune system supplements can prevent bacteria from adhering to cells. Some immune system supplements like black geranium (Pelargonium sidoides), have been shown to block bacteria from binding to cells, which makes it harder for them to infect you.

According to a 2011 study, evidence for a potent anti-adhesion principle of the Pelargonium sidoides root extract is significantly present. However, the blocked adhesion molecules still need to be identified in further clinical studies (20).

Another 2008 meta-analysis that analyzed research from 5 electronic databases showed that black geranium is effective at treating acute bronchitis (21).

Immune system supplements can support the development and function of various immune system cells. Vitamin C is a potent antioxidant that helps bolster the immune system by organizing and facilitating the development of various immunity cells.

This is why it’s been shown to reduce the likelihood of contracting a virus. It has also been shown to reduce the duration of colds when you are sick (22).

Side effects

Immune system supplements may cause IBS like symptoms. As with all supplements, it’s recommended that you always follow the instructions on the label for the best dosages. As long as you do not exceed the recommended daily intake, you should not see any side effects from taking these supplements. 

In case you do exceed the recommended dose, or you combine the immune system supplements with other supplements, you may experience IBS like side effects such as nausea, vomiting, diarrhea, or stomach problems. However, this is extremely rare and only when taken in extremely high dosages.

Immune system supplements may interact negatively with certain medications. If you suffer from a preexisting condition, are taking medication, immune system supplements may interact negatively and cause adverse reactions. You should speak to your doctor before taking an immune system supplement that is 

Immune system supplements may harm the immune system. Men who consumed 300mg of zinc per day over six weeks showed compromised immune system functioning, including the lack of activation of phagocytosis of neutrophils (23).

Immune system supplements may aggravate auto-immune disorders.  If you have an auto-immune condition, it can be aggravated by using immune system supplements like American ginseng. 

Immune system supplements like may cause organ donation issues. American ginseng has been shown to improve the immune system, which can be dangerous for people who have had an organ transplant.

This is because an enhanced immune system might target the foreign organ and try to destroy it. It may also interfere with organ transplant medication, which is used to minimize the chance of rejection. 

Immune system supplements like may damage organs.  While rare, consuming over 7g of vitamin C per day can cause Oxalate Nephrotoxicity, also known as kidney toxicity. 

Some medicinal mushrooms, like Reishi, may also cause organ damage. Specifically, reishi mushrooms can cause liver toxicity. However, more studies are needed to confirm this. 

Immune system supplements may cause hypercalcemia and weaken your bones. Vitamin D is a popular immune system supplement, that can cause too much calcium in your blood, also known as hypercalcemia. Vitamin D can also cause low vitamin K2 levels, which can expedite bone loss. 

Immune system supplements may cause allergic reactions. Immune system supplements often contain a mix of ingredients, which increases the chance of an allergic reaction. If you know you are allergic to an immune-boosting ingredient, it’s important to check the label before consuming a supplement. 

Immune system supplements may damage a baby’s health. There isn’t enough research to show that all the ingredients used in various immune-boosting supplements are safe for pregnant women and fetuses. As such, pregnant women should consult a doctor before taking any immune system supplement. 

Immune system supplements might release toxic cyanides. The elderberry plant contains substances called cyanogenic glycosides, which can release toxic cyanide in certain cases. 

Recommended dosage

Immune system supplements should be consumed based on the manufacturer’s directions on the bottle. That being said, there are a few guidelines you should know for the individual ingredients that are often included in various immune system supplements. 

For zinc, 80 to 100 milligrams per day has been shown to be effective in reducing colds. However, some people who consume more than 40mg per day, which is the tolerable upper intake level, can experience side effects. 

Vitamin C has been shown to be effective at reducing cold duration when consumed between 1-8g per day. 

Regarding vitamin D, the RDA set the US government is believed to be too low for persons living in the northern hemisphere. According to the Institute of Medicine, the safe upper limit is between 2000 and 4,000 IU per day (24).  

For black geranium, the clinically effective dosage is around 800 mg of the raw plant. For garlic extract, 600 and 1,200 mg seems to be effective. 

For Amrit, the clinically effective dose is 300 mg.

For American ginseng, between 400 and 1,125 mg seems to be effective. Ginseng should happen cycled every 2-3 weeks and consumed before meals to maximize absorption and benefits (25).

Different mushrooms will have different doses in terms of boosting the immune system. A good starting point for Cordyceps is around 200mg. Shiitake mushroom extracts can be used up to 6 months at a time, for around 8g a day. Everyone will find a different sweet spot with mushrooms, so it’s important to experiment. 

Elderberry comes in different forms, so it’s important to know the dosage for each from before consuming. Elderberry syrup has been used in studies at 15ml per serving to treat influenza. When consuming elderberry juice, 400ml has been shown to provide antioxidant properties and help the body combat free radicals and systemic stress. 

Elderberry may cause stomach discomfort for some people, so you should always start on the lower end and titrate up. 


When is the best time to take immune system supplements? Immune system supplements can be taken at ay point of the day. For better nutrient absorption, you might want to take them right before a meal or with a meal. Some vitamins may be a little bit stimulating, so taking them right before bed is not recommended. 

Can you take immune system supplements indefinitely? Theoretically, you can take immune system supplements for as long as you want. However, some supplements, like ginseng, mushrooms, and garlic extract, should be cycled for maximum potency.

There are also no long term studies yet that show negative (or positive) effects of indefinite supplementation of immune system supplements. As long as the supplements are natural, you shouldn’t have any issues consuming them for a long time. 

What are immune system supplements mainly designed for? The main purpose of these supplements is to give your body’s defense system some extra support. They contain vitamins and minerals that naturally and safely help improve your immune system.

How long does it take for supplements for the immune system to work? This depends on the specific supplement, as the bioavailability might vary. The form of the supplement affects this as well. When taking an immune defense supplement specifically to fight a respiratory infection, for example, a lozenge may work quicker and more effective than a pill.

Are supplements for the immune system natural? Most of them are 100% natural, but this depends on the specific supplement. Generally, the best supplements for the immune system are completely natural to make sure you don’t receive any artificial ingredients that might potentially harm your body.

Are immunity-boosting supplements vegan? Since most of them are natural, most of them will be vegan and vegetarian as well. Nevertheless, always check the label of a product to be sure.

Do immune system supplements protect me from diseases? To a certain degree, yes. By supporting your immune system, these supplements give your body more tools and strength to fight off diseases. However, this does not mean they are some magic cure or wonder medicine. Immune system supplements are only to give your body’s immune system additional support.

Do immune system supplements protect me against the coronavirus? These supplements are NOT a cure or a form of medication to protect you from COVID-19, and any supplement provider claiming this should be avoided at all times.

However, the healthy and natural ingredients in many of the supplements may have a beneficial effect in terms of supporting your immune system and helping it fight off viruses, such as COVID-19.

Does everyone need immune system supplements? If you live a healthy lifestyle, you might not need immune system supplements per se. However, the natural vitamins and minerals in these supplements may be beneficial for many people of all ages and genders.

Can I use supplements for the immune system if I am pregnant or breastfeeding? Most immune system supplements should be safe to take when you are pregnant. However, we do recommend you double-check with the specific supplement you are taking, as some of them might contain harmful ingredients for pregnant women.

If you are pregnant or breastfeeding, we strongly advise you to speak to your doctor before taking any supplements.

Can I use these supplements if I am using another medication? Since most immune system supporting supplements are natural, you should not notice any problems from taking them alongside other medication. Nevertheless, we advise you to always first speak to your doctor before taking any supplements.

Can I use these supplements if I am using another supplement? If you are using natural supplements, you should normally not witness any problems from taking multiple supplements alongside one another. However, it is advised that you follow the recommended dose for each supplement and keep an eye on whether you start noticing any potential side effects.

Do supplements for the immune system help you lose weight? While they are not designed to do so, immune-boosting supplements may support weight loss by providing you with healthy nutrients that might positively influence your metabolism.

Are immune system supplements antiviral? Immune system supplements in themselves are not antiviral but may contain ingredients that are. For example, Elderberry Extract and its formulations help to activate the healthy immune system by increasing inflammatory cytokine production.

Is alcohol bad for the immune system? Yes, alcohol can handicap immune system functioning, making it more likely to develop infectious diseases. One study showed that people who have more than seven drinks a week were more likely to be hospitalized for pneumonia than a person who consumed six or fewer drinks in the same time frame (26).

However, this doesn’t apply as much to people who are used to drinking a significant amount on a consistent basis. 

Which foods help improve the immune system? The best foods to boost the immune system include ones that provide a wide variety of minerals and nutrients and that are anti-inflammatory. Furthermore, foods that are low in sugar and high in beneficial gut fiber or probiotics will also be good for the immune system. Some of the best foods include citrus fruits, vegetables, fermented foods, and some spices like turmeric. 

What lifestyle factors weaken the immune system? Various lifestyle factors can weaken the immune system, such as consuming alcohol, drugs, unhealthy foods, not exercising, and not following a proper hygiene routine. 

Can vitamin C help the immune system? Yes, vitamin C helps reduce oxidative damage and boosts the body’s antioxidant profile. This helps make you less likely to catch a cold. 

Are immune system supplements safe for pregnant women and breastfeeding? Immune system supplements are generally considered safe for pregnant and breastfeeding women. However, some ingredients may not be suitable for these populations, so you should speak to your doctor before consuming an immune system supplement.

Do all immune-boosting mushrooms improve the immune system? No, not all medicinal mushrooms improve the immune system. Some of them improve blood flow, athleticism, and even cognition. Regarding immunity, one of the best mushrooms to consider is Shiitake. 

Do immune system supplements speed up the recovery from a cold? Yes, some immune system supplements, such as elderberry, can speed up the recovery from a cold. Research shows that elderberry can reduce the length of a cold (27).

However, it does not accomplish this directly. Instead, it improves the body’s antioxidant profile by providing it with vitamin C and polyphenols. 

Can immune system supplements boost antioxidant activity in the body? Yes, some ingredients found in immune system supplements can boost antioxidant activity int eh body. Elderberry is one supplement that can boost antioxidant activity and reduce oxidative stress.

Are multivitamins considered an immune system supplement? No, multivitamins are not considered an immune-boosting supplement. While they may support the immune system through various ingredients, they often don’t’ contain the clinically effective dosages of immune-boosting ingredients that are necessary for proper support. 

Do immune system supplements help patients with AIDS? AIDS is a detrimental disease that leaves your body vulnerable to contracting various infections. Some immune system supplements, like elderberry, support the body’s immune response, allowing you to fight off infections when your immune system is compromised (28).

However, it should be noted that elderberry, or any immune system supplement, should not be used as the sole treatment or management of AIDS. 

Does vitamin D protect against infection? Yes, vitamin D can boost the immune system, which helps protect against viral infections like the flu. However, it does seem to be more effective in people, and during times when vitamin D deficiency tends to be higher. A 2010 study showed that vitamin D3 supplements could help reduce the likelihood of catching the flu (29).

There is also research showing that vitamin D deficiency is correlated with an increase in respiratory tract sickness (30).

Related Articles


Immune system supplements can be a great solution if you are looking for a natural way to give your immune system some extra support. By adding natural ingredients such as zinc and vitamin C to your diet, you can help your immune system protect your body against viruses and bacteria.

When formulated well, immune system supplements can support your body’s immune system by improving natural killer cells, reducing inflammation, and preventing free radical damage. 

For BodyNutrition‘s #1 recommended immune system supplement, click here.


John Davis