Health & Wellness

The Top-Rated Immune-Boosting Supplements of 2021

Peter Gold
Health Editor

Peter is a practitioner of naturopathic medicine, applying his craft in the Pacific Northwest. His passion is preventive care and self-healing. His philosophy is healthy habits help people live their lives to the fullest.

How We Found the Best Immune-Boosting Supplements

Over the last year, most Americans have taken a serious interest in strengthening their immune system. Zinc has long been recognized as the go-to anti-viral mineral. New research has shown that combining zinc with specific proven vitamins and herbs can further improve the body’s natural ability to defend against harmful viruses.

With immune health being top of mind for so many, it is no surprise that hundreds of immune-boosting supplements are flooding the marketplace. While these supplements all promise to deliver benefits, the reality is that many fall short. Some of the most popular brands use ineffective or insufficient doses of ingredients, and many contain low-quality fillers.

How To Pick A Good Immune-Boosting Supplement &
Avoid The Junk

With so many options, it seems many of us might still be unclear about what to look for in a quality immune system supporting supplement. To help cut through the clutter, we have compiled months of research about which are the key ingredients that have been shown in studies to benefit your immune health.

This short guide will help you know what to look for and what to avoid so you can make an informed decision when it comes to your immune-boosting needs. We will also list out the top 5 immune-supporting supplements sold today.

Let’s take a moment to understand precisely how immune system supplements work to improve your ability to fight off viruses and why it’s essential to add it to your daily routine.

Immune-Boosters:
What Are They All About?

With over 200 harmful virus species continuing to mutate, it is critical to keep your immune system functioning in tip-top shape. While antibiotics work wonders at battling bacterial infections, they have no impact on viruses such as the flu and the common cold. A quality immune-boosting formula will combine anti-viral vitamins, minerals, and herbs proven to support your body’s ability to defend against disease-causing viruses. The correct combination can help fortify the immune system by triggering white blood cells. These cells encompass B-cells, which produce antibodies and help alert the T-cells, which destroy compromised cells.

A Good Immune Supplement Can:

Strengthen the immune system4

Enhance Immune System Response5

Help prevent the development of viruses6

Decreased odds of developing cold or flu7

Shorten duration and severity of cold or flu8

Lessen the severity of upper respiratory symptoms9

Fight inflammation and stress10

Improve allergy symptoms11

4 Things To AVOID
When Buying An Immune Supplement

1. VITAMIN D

Contrary to the name, vitamin D is a hormone that plays an integral part in the immune system’s strength. Without sufficient vitamin D, one can experience more frequent colds or flu, fatigue, loss of bone mass, body pain, and even affect your mood.12-14 An alarming statistic is that 42% of the US population is deficient in vitamin D, with Hispanics over 69% and African Americans over 82%.15 Common risk factors include dark skin, the elderly, living in the northeast, and lack of sunlight. Due to the recent health crisis, spending more time indoors may have compounded the problem.16 Some manufacturers include vitamin D in immune support formulas. We feel this can give you a false sense that you are achieving the correct levels needed. It is essential to get a blood test to determine if you are deficient. For this reason, we recommend avoiding immune-boosting formulas that include vitamin D. Let your doctor advise on the right dosage required to get your levels back in line.

2. PROPRIETARY BLENDS

In reviewing the labels of immune supplement brands, we found several manufacturers listing ingredients in groups named Proprietary Blend, Immune Support Blend, or a trademarked phrase. These “blends” do not show each ingredient’s exact amount but rather the total amount for the entire group’s ingredients. You deserve to know if you are getting 1 mg or 15 mg of zinc. Manufacturers can also drastically change the proportions of ingredients in their blend without disclosing these changes to you. This change can leave you wondering why a product that used to work for you is no longer seeming effective. It is best to avoid wasting your hard-earned money on immune support brands that use proprietary blends.

3. RELYING ON AMAZON REVIEWS

Research showed that in March 2019, there were 1.8 million new unverified reviews, with an average of 99.6% of them being 5-star reviews.17 Most of these reviews are from people paid to write them. These fake reviews inflate the number and overall star rating of a product. When deciding on a product that can impact your health, don’t rely on Amazon reviews as they can be extremely misleading.

4. INSUFFICIENT RETURN POLICY

A reputable immune-boosting supplement brand will demonstrate they have faith in their product by offering a 100% money-back guarantee policy. Some try to complicate their refund policies by placing limitations on what kind of returns they will take. Avoid any brand that does not have at minimum a no questions asked 90-day money-back guarantee.

Top 4 Criteria For A Quality
Immune-Boosting Supplement

When it comes to immune-boosting formulas, not all are created equal. With thousands of different vitamins, minerals, and herbs, only a handful have substantial research supporting immune benefits. Below are the four most essential ingredients to consider before deciding which brand is best for your needs.

2021’s Top Immune-Boosting Supplements

Our review encompassed 85 different immune system boosting supplements, putting each through our rigorous Review Scout assessment process. To determine 2021’s Top 5 Immune-Boosting Supplements, we looked for predicted effectiveness, safety, return policy, and overall customer satisfaction.

#1 Stonehenge Health Dynamic Immunity

A+

Overall Grade

#1 Stonehenge Health Dynamic Immunity

  • OVERALL RATING 9.7/10
  • Predicted Effectiveness 9.8/10
  • Ingredient Quality 9.8/10
  • Value 9.5/10
  • Return Policy 9.8/10
  • User Rating 9.6/10
PROS
  • Contains Zinc, Glutamine, Elderberry, and Echinacea
  • Includes Turmeric with 95% Curcuminoids to improve Zinc absorption
  • Lists exact amounts for all 10 vitamins, nutrients, minerals, and probiotic
  • Endorsed by a Doctor
  • Vegetarian Capsules, Gluten, Sugar, and Hormone-Free
  • Verified 90-day 100% money-back return policy
CONS
  • Often out of stock due to high demand
Why We Chose It

Stonehenge Health’s Dynamic Immunity is Review Scout’s top choice. This supplement contains all four-essential immune-boosting ingredients Zinc, Glutamine, Elderberry, and Echinacea.

In reviewing dozens of immunity-boosting brands, we found that very few have addressed zinc’s absorption challenge. We were impressed that Stonehenge Health includes turmeric curcumin in 95% strength, which studies have shown to improve zinc absorption. They go a step further and include essential vitamins C, E, and B6, garlic, and the probiotic Lactobacillus Acidophilus, which have all been shown to help improve the immune system’s strength.

This formula does not contain any synthetic fillers, binders, or artificial ingredients. It simply has the critical ingredients listed on the label with their exact dosages, in a vegetarian capsule, and that is it. With a pure and clean formula, Dynamic Immunity has what it takes to help you fight off the cold, flu, and viruses by supporting a robust immune system.

Stonehenge Health backs its products with a no-questions-asked, 90-day money-back guarantee and is one of the few brands to be endorsed by a board-certified physician. We also like that they offer customers discounts on bundles. Click on the link below to see their current specials.

*Results are based on user-generated experiences with these products, and individual results may vary. Please refer to the manufacturer’s product website for detailed information.

#2 Source Naturals Wellness Formula

A-

Overall Grade

#2 Source Naturals Wellness Formula

  • OVERALL RATING 9.0/10
  • Predicted Effectiveness 9.2/10
  • Ingredient Quality 9.1/10
  • Value 9.6/10
  • Return Policy 7.6/10
  • User Rating 9.3/10
PROS
  • Contains Zinc, Elderberry, and Echinacea
  • Gluten-Free
  • Lists amounts for all 31 vitamins, nutrients, and minerals
CONS
  • Does not contain Glutamine
  • Does not contain Turmeric for Zinc absorption
  • Must take 6 gelatin pills per dose
  • Contains allergen Soy
  • User complaints of indigestion and heartburn
  • Return policy limited to point of purchase
Why We Chose It

Source Naturals is a popular brand, and their Wellness Formula has been sold for many years. This product contains thirty-one different vitamins, minerals, and nutrients, including zinc, elderberry, and echinacea. We were disappointed to see that with so many ingredients, the product was missing glutamine, critical to immune cells such as T-cells and B-cells, and a method to improve zinc absorption such as turmeric 95% curcumin.

While we applaud Source Naturals’ desire to offer a wide variety of ingredients, it is relatively pointless since many consumers have complained it is too hard to consume the required daily dosage of 6 large gelatin capsules. Complaints of indigestion and heartburn may also be related to the large dosage requirement, the number of ingredients, and the use of gelatin capsules instead of consumer-preferred vegetarian capsules.

Source Naturals website has no mention of any money-back guarantee, and so consumers are stuck relying on what may be a limited return policy from the point of purchase.

*Results are based on user-generated experiences with these products, and individual results may vary. Please refer to the manufacturer’s product website for detailed information.

#3 Olly Active Immunity Gummy

B

Overall Grade

#3 Olly Active Immunity Gummy

  • OVERALL RATING 8.3/10
  • Predicted Effectiveness 8.7/10
  • Ingredient Quality 8.9/10
  • Value 8.4/10
  • Return Policy 7.6/10
  • User Rating 7.8/10
PROS
  • Contains Elderberry and Echinacea
  • Gluten-free
CONS
  • Contains very low dosage of Zinc
  • Does not contain Glutamine
  • Contains 3 grams of sugar per serving
  • Limited 30-day Return Policy
Why We Chose It

Olly Active Immunity Gummy is a product popular with those who prefer gummies to take vitamins. This formula contains zinc, elderberry, and echinacea. While it is good to see it has three of the top-four immune-boosting ingredients, the dosages offered are very low, with only 5 mg of zinc, 65 mg of elderberry, and 40 mg of echinacea per serving. These levels are about 20-30% of the amount offered by the top-rated brand on our list, requiring you to take as much as 15 gummies per serving to match it. If you consider that three gummies pack 3 grams of sugar per serving, you would be consuming 15 grams of sugar per day, almost as much as a candy bar, to match the top-rated brand’s dosage level. Olly Active Immunity Gummy’s sugar content may not be appropriate for those watching their blood sugar levels or other health-conscious consumers. Another issue is that Olly is missing glutamine and an ingredient to improve zinc absorption, such as turmeric 95% curcumin. Olly backs their product with a very limited 30-day refund period.

*Results are based on user-generated experiences with these products, and individual results may vary. Please refer to the manufacturer’s product website for detailed information.

#4 Medicove Health Immune Support Supplement

C

Overall Grade

#4 Medicove Health Immune Support Supplement

  • OVERALL RATING 7.4/10
  • Predicted Effectiveness 7.5/10
  • Ingredient Quality 7.5/10
  • Value 7.6/10
  • Return Policy 7.2/10
  • User Rating 7.4/10
PROS
  • Contains Zinc
  • Contains ionophore Quercetin for zinc absorption
CONS
  • Does not contain Elderberry, Echinacea, or Glutamine
  • Conflicting dosage and servings per bottle
  • User complaints related to headaches, nausea, and indigestion
  • Does not use vegetarian capsules
  • No money-back guarantee
Why We Chose It

Medicove Health Immune Support Supplement contains zinc. We were pleased to see the inclusion of quercetin, which, like turmeric 95% curcumin, is an ionophore that supports zinc absorption. However, the formula lacks the other top-ranking ingredients on our list glutamine, elderberry, and echinacea. While this brand includes vitamin D3, we feel it is essential to consult your physician and arrange for a blood test to determine if you are deficient and to what extent. Vitamin D3 is critical to your health, and formulas containing D3 can give you a false sense that you are achieving optimal levels. This brand’s label directions state you should take two gelatin capsules per day, but the more prominent supplement facts say a serving size is just one capsule per day with 60-servings in a bottle. If you are to follow the directions, the bottle only is offering a 30-day supply. The lack of transparency is concerning. Medicove Health appears to be a brand created for the sole purpose of selling on Amazon. As is such, their website has no mention of any available money-back guarantee, and so consumers are stuck relying on Amazon’s limited return policy.

*Results are based on user-generated experiences with these products, and individual results may vary. Please refer to the manufacturer’s product website for detailed information.

#5 Immuneti Advanced Immune Defense

D+

Overall Grade

#5 Immuneti Advanced Immune Defense

  • OVERALL RATING 6.9/10
  • Predicted Effectiveness 6.8/10
  • Ingredient Quality 7.3/10
  • Value 6.8/10
  • Return Policy 7.5/10
  • User Rating 6.2/10
PROS
  • Contains Elderberry and Echinacea
  • Gluten, dairy, and soy-free
CONS
  • Does not contain Glutamine
  • Does not contain an ingredient for zinc absorption
  • Consumer complaints of bait and switch sales
  • User complaints related to headaches, nausea, and indigestion
  • Quality control complaints of missing pills and blurry labels
  • Limited 30-day Return Policy
Why We Chose It

Immuneti Advanced Immune Defense is a product made famous thanks to their massive spending on internet advertising. In recent months, the brand has also become infamous for what appears to be some bait and switch sales techniques. Immuneti advertises that their formula contains zinc, elderberry, echinacea, vitamin C, garlic, vitamin D3, and black pepper. Like most immune-boosting formulas, Immuneti is missing the all-important glutamine and an ingredient to improve zinc absorption, such as turmeric 95% curcumin.

In June of 2020, consumers began complaining that the bottles they received were missing vitamin D3 and black pepper from the label, and the amount of vitamin C went from the advertised 330 mg to 180 mg. Upon inquiry, Immuneti responded saying, “By placing an order you will receive immuneti™ with Vitamin D3.” Unfortunately, that was not the case, and as recent as January 2021, a verified purchaser complained that the bottle received was missing vitamin D3 from the label. The brand even went as far as to state, “Hello, we are happy to say these are authentic immuneti bottles!” An even larger issue for us is that in June of 2020, a consumer inquired, “Are the ingredient amounts listed based on 2 or 4 pill serving?” in which Immuneti replied, “The ingredients listed are for a 4 pill serving.” The label clearly states that the dosages provided are for a serving size of 2 pills. Since there are only 60 capsules in a bottle, based on 4-capsule serving size, each bottle is only a 15-day supply. What may seem like a bargain-priced product is far from that. Ultimately, while some users have reported benefits from taking Immuneti, we recommend avoiding this brand due to the numerous consumer complaints and the limited 30-day return policy.

*Results are based on user-generated experiences with these products, and individual results may vary. Please refer to the manufacturer’s product website for detailed information.

Citations
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