Disclaimer: None of the information in this article constitutes medical advice. All statements are merely the opinion of the writer(s). We recommend that patients follow their doctor’s guidance in regard to cold and flu prevention and treatment.
Emergen-C is one of the most popular over-the-counter (OTC) supplements sold in the U.S. It’s a fizzy vitamin C tablet used for immune support, and the brand claims that “Emergen-C products contain a powerful blend of nutrients to support your immune system.”
But does Emergen-C contain ingredients shown in medical studies to enhance immune function, or is this just a marketing claim? Do their products contain any unhealthy additive ingredients? Is Emergen-C Immune Plus more effective than regular Emergen-C? And are all the supplemental vitamins and minerals really necessary?
In this article we’ll answer all of these questions and more, as we analyze the ingredients in Emergen-C based on medical studies to give our take on whether the brand is healthy or unhealthy, and which formulation is more likely to be effective.
We'll share our thoughts on whether the large number of supplemental vitamins and minerals is really necessary in a cold and flu support product.
Emergen-C Ingredient Analysis
The most popular Emergen-C product is Emergen-C Immune Support, which is the brand’s original formula and the one you’ll see at most drug stores.
It comes in a variety of flavors, and the ingredients in the “Super Orange” flavor are listed above.
Vitamin C is arguably the most important ingredient, and Emergen-C provides 1,000 milligrams (mg) of vitamin C.
An extensive medical review analyzing data from over 11,000 trial participants found that vitamin C supplementation at or above 1,000 mg daily reduced the duration of colds by 8% in adults and 18% in children.
Zinc is a mineral that is also shown in medical research to significantly reduce the duration and severity of the common cold in healthy individuals, but it may be underdosed in Emergen-C.
This supplement only provides 2 mg of zinc, while the above-linked meta-study suggests a therapeutic dosing range between 30 mg and 160 mg per day to treat the common cold.
While Emergen-C contains some potentially effective ingredients, it also contains a number of ingredients we consider to be questionable from a health perspective.
Added sugar is included at a dose of 6 grams (g) per tablet.
As we referenced in our Pedialyte reviews article, excess intake of added sugar is associated with a wide range of negative health effects like obesity and type 2 diabetes, and many Americans already consume too much added sugar from diet.
Citric acid is a preservative and flavor enhancer shown to cause whole-body inflammatory reactions in a small subset of patients, according to a series of medical case reports published in the Toxicology Reports journal.
Natural flavors is a broad descriptor that fails to identify the specific chemical compounds used as flavoring agents. There are documented toxicity concerns regarding some flavoring agents.
Overall, we consider Emergen-C potentially effective for preventing and reducing the duration of illness due to its effective dose of vitamin C, but we consider this supplement unhealthy due to the inclusion of a number of questionable additive ingredients.
Is Emergen-C Immune Plus Better?
Emergen-C sells an “Immune Plus” product with a slightly different formulation. The ingredient list above is from the “Super Orange” flavor of Emergen-C Immune Plus.
This supplement contains vitamin C, zinc, added sugar, citric acid and natural flavors, so our comments from the previous section about all of these ingredients apply here as well.
Arabinogalactan is included in a proprietary (prop) blend with an average ingredient dose of 250 mg.
This compound was shown to enhance immune function and decrease incidence of cold episodes by 23% in a 2016 medical review, but the minimum dose used in any of the studies was 1,500 mg, or 600% of the likely amount in Emergen-C Immune Plus.
Beta-glucan is a type of soluble fiber included in the same prop blend.
This appears to be an effective dose, as a clinical trial published in the Journal of Dietary Supplements found that participants taking beta-glucan at the same dose as in Emergen-C experienced a 37% reduction in the number of cold and flu symptom days compared to participants taking placebo pills.
Overall, we consider Emergen-C Immune Plus more likely to be effective for cold and flu symptom reduction than Emergen-C Immune Support, because the "Plus" version has two active ingredients with research backing, and the zinc dose is 5x higher in this version.
We do not currently recommend this supplement overall, due to the inclusion of a number of questionable additive ingredients like added sugar and citric acid.
Are Some Vitamin Doses Too High?
We’ve established that vitamin C and zinc have some research backing for cold and flu prevention and treatment.
However, as you can see from the ingredient labels shown in the previous sections, Emergen-C supplements contain a large number of other vitamin and mineral additives.
Emergen-C Immune Support contains 14 vitamins and minerals outside of zinc and vitamin C. We cannot identify medical research suggesting that the majority of these nutrients have any effect on cold and flu, and we do not understand their inclusion in an immune-enhancing formulation.
Emergen-C is not a multivitamin; it’s a supplement that consumers use with a targeted purpose — to enhance immune system function and reduce symptoms of cold and flu. So in our opinion, it’s illogical to include a large number of vitamins and minerals without providing evidence that these ingredients support that goal.
Regularly using supplements containing a large number of added vitamins and minerals can cause elevated and unsafe blood levels of those vitamins and minerals in some consumers.
In early 2022, a wellness brand had to remove some of their products from the market because the supplemental vitamins and minerals were causing toxicity in some customers, as we documented in our article on is Muscle Milk bad for you.
Some consumers taking Emergen-C may also be taking a multivitamin concurrently, potentially increasing this risk.
We want to note that the doses of minerals and fat-soluble vitamins in Emergen-C are relatively low, and we're not particularly concerned about this risk in relation to this supplement, but we felt that it was worth discussing in this article.
Our Clean Immune Support Picks
MBG Vitamin C Potency+ is our top value immunity pick.
Vitamin C was shown to reduce the duration of colds by over 10% in a 2013 medical review, and this supplement also contains a citrus bioflavonoid complex.
Performance Lab Immune is our top premium immunity supplement.
This supplement contains the patented postbiotic IMMUSE, which is backed by 15 clinical trials and is clinically shown to activate a specific type of immune cell that helps fight infection and support overall wellness.
Pique Daily Radiance is our top food-based immune supplement.
This gel provides 1,000 mg of vitamin C per serving, and also contains organic elderberry juice concentrate, which is clinically shown to support the immune system.