Key takeaways:
Immunity support products, such as Emergen-C and Airborne, are over-the-counter products that aim to boost your immune system. They probably won’t prevent you from getting sick. But they may help you feel better a little faster.
Emergen-C and similar products are generally safe, but have side effects and drug interactions to consider. So it’s best to check with your prescriber or pharmacist before taking them.
Low levels of certain vitamins and minerals can make your immune system less effective. So be sure to have regular check-ups with your primary care provider to ensure your levels are where they should be.
No one wants to be sick. We all hate that icky feeling: the runny nose, congestion, and body aches and pains. Plus, none of us have time for illness. Being sick isn’t something that fits into our busy schedules.
So it’s no surprise that many people turn to over-the-counter (OTC) supplements to help boost their immune system. These include products such as Emergen-C and Airborne. And people often take them to prevent illness or to get better faster when symptoms appear. But does Emergen-C (and products like it) actually work?
What is Emergen-C?
Emergen-C is a line of OTC supplements marketed for supporting your immune system. It comes in several different forms, from chewable tablets and gummies to powder packets you mix with water and drink. Each type of Emergen-C contains different active ingredients, but the main ingredient in most of them is vitamin C.
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Some other ingredients you’ll find in Emergen-C products include:
Antioxidants such as vitamin E
Electrolytes such as calcium, sodium, and potassium
Caffeine
Sugar or other carbohydrates
Melatonin to help you sleep
Since Emergen-C is considered a dietary supplement, the manufacturer can’t make any claims that it treats or prevents illness. So these products simply say that the individual vitamins and minerals inside them help support your immune system. But just because a vitamin or mineral supports your immune system doesn’t necessarily mean that taking these products will keep you from getting sick.
Does Emergen-C work?
Overall, there’s mixed evidence about the effectiveness of the vitamins and minerals included in immunity support products like Emergen-C. Most research shows that it’s only helpful to take vitamins if you don’t get enough from your regular diet. And you need to take vitamins daily to get any benefit, not just when you’re feeling sick. So taking Emergen-C or similar products isn’t likely to prevent you from getting sick. But it is possible they may help you feel better a little faster.
Low levels of some vitamins and minerals can weaken your immune system. But taking extra amounts won’t necessarily treat or prevent infections like the common cold. In many cases, your body just gets rid of extra vitamins and minerals you consume when you pee. So your money may literally be going down the toilet.
That being said, since the ingredients in these products are usually low risk at normal doses, they’re not likely to cause you any harm. So if you feel like they help you stay healthy during cold and flu season, it’s fine to take them as long as you have your healthcare team’s OK to do so.
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Let’s go into more detail as to what the research says about vitamin C, vitamin D, and zinc — three ingredients in Emergen-C that are often marketed as products to prevent or treat the common cold.
Vitamin C
There’s no good evidence that taking vitamin C will keep you from getting a cold unless your vitamin C levels are low.
Studies do show that taking 200 mg of vitamin C every day on a regular basis may help reduce how severe your cold symptoms are and how long they last. But you need to take vitamin C consistently to get this benefit — not just when you’re worried about getting sick. Higher doses had a greater effect, but it’s not recommended for adults to take more than 2,000 mg of vitamin C per day.
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If you only take vitamin C when you feel a cold coming on, it doesn’t seem to do much — even at high doses. Most clinical studies show no difference between vitamin C and a placebo (sugar pill). The one benefit may be that your body seems to use more vitamin C when you have a cold. So taking higher doses of vitamin C while you’re sick may help keep your levels up.
Vitamin D
Similar to vitamin C, low vitamin D levels may make you more likely to get a cold or the flu. In this case, taking vitamin D may help reduce the number of times you get sick throughout the year.
The evidence is mixed, however, as to whether or not taking vitamin D can help limit how often you’re sick if your vitamin D levels are normal. Some studies show a minor benefit, but others show no benefit at all. Plus, vitamin D likely won’t have any effect if you take it after you already have a cold or the flu.
Zinc
Your body needs zinc in order to make the cells that power your immune system. High doses of zinc (more than 75 mg per day) may help reduce how long cold symptoms last. But you need to start taking it within 24 hours of your first symptoms.
Keep in mind that most studies looked at zinc in a lozenge (candy) on its own, not in a chewable tablet or drinkable powder combined with other supplements. And a 75 mg dose of zinc is almost double the maximum recommended amount for adults. It’s best to get a healthcare professional’s OK before taking more than 40 mg of zinc daily.
Other ingredients
Other ingredients in products like Emergen-C may give you a false sense of “feeling better” when you take them. This includes caffeine and sugar, which can give you a temporary energy boost. Melatonin may help you sleep better when you’re not feeling well. And electrolytes can help you stay hydrated and keep your energy levels up, especially if you have a fever or diarrhea. But there’s no evidence these ingredients help keep you from getting sick or help you feel better faster.
Emergen-C side effects and risks
OTC products like Emergen-C are generally considered safe for most people. But there are some risks to consider. Each individual ingredient has side effects and drug interactions that could affect your health. This is especially true if you take more than the recommended amount.
For example, large doses of vitamin C can cause nausea, diarrhea, and stomach cramps. Vitamin C may also interfere with certain cancer treatments, such as radiation or chemotherapy.
Too much zinc can cause stomach pain, nausea, and diarrhea. It can also affect iron levels and may lower your immunity if you take too much on a regular basis.
Taking more vitamin D than recommended can lead to high calcium levels in the blood. And very high vitamin D levels can cause kidney failure and heart problems.
It’s best to check with your healthcare team or pharmacist before taking an immunity support product like Emergen-C. Make sure to give them an updated medication list to review. This can help them make sure there aren’t any drug interactions or health risks that could make these products unsafe for you.
Airborne vs. Emergen-C: Is one product better than the other?
Not really. The vitamins and minerals in Airborne and Emergen-C products are similar. And neither supplement has been proven effective in clinical studies. They also haven’t been compared to one another in head-to-head studies. So the difference between them mainly comes down to your personal preference for taste, flavors, and dosage forms.
What else can you do to keep from getting sick?
A balanced diet and a healthy lifestyle are the best ways to keep your immune system healthy. Health experts say the most effective method for preventing illness is to wash your hands often and keep them away from your eyes and nose during cold and flu season.
Still, it’s clear that low levels of certain vitamins and minerals in your body can have a negative effect on your immune system. So making sure you get enough of them through your diet (or supplements, if needed) is key. Your primary care provider will typically check these levels every year as part of your annual physical. And they’ll let you know if any levels are low and what steps you should take. So keeping these appointments is a good way to protect your health.
Frequently asked questions
It depends on the product. Most Emergen-C immunity support products recommend a once-daily dose. You shouldn’t take more in an effort to get better results. Taking too many vitamins or minerals can lead to unwanted side effects or be harmful to your health. So be sure to read the product label and follow the dosage instructions for the product you’re taking.
The carbohydrates and electrolytes in Emergen-C may help a hangover, especially if they’re in a form that’s mixed with water. Alcohol can dehydrate you, so these ingredients can help improve hydration. But there’s little evidence the other ingredients in Emergen-C will make a difference in your hangover symptoms.
Drinking Emergen-C every day is similar to taking a daily multivitamin supplement. But be aware that different types of Emergen-C contain different ingredients, and not all are safe to take on a regular basis. Talk to your pharmacist or prescriber before taking a product like Emergen-C on a daily basis.
It depends on the product. Most Emergen-C immunity support products recommend a once-daily dose. You shouldn’t take more in an effort to get better results. Taking too many vitamins or minerals can lead to unwanted side effects or be harmful to your health. So be sure to read the product label and follow the dosage instructions for the product you’re taking.
The carbohydrates and electrolytes in Emergen-C may help a hangover, especially if they’re in a form that’s mixed with water. Alcohol can dehydrate you, so these ingredients can help improve hydration. But there’s little evidence the other ingredients in Emergen-C will make a difference in your hangover symptoms.
Drinking Emergen-C every day is similar to taking a daily multivitamin supplement. But be aware that different types of Emergen-C contain different ingredients, and not all are safe to take on a regular basis. Talk to your pharmacist or prescriber before taking a product like Emergen-C on a daily basis.
The bottom line
Immunity support products like Emergen-C and Airborne typically contain several different vitamins and minerals. Although they’re intended to help boost your immune system, there’s not a lot of evidence that they’re effective at preventing illness. However, some of their ingredients, such as vitamin C and zinc, may help you feel better faster or lessen the severity of your cold symptoms.
Emergen-C and other immunity support products are generally safe, but they do have side effects to consider. So it’s best to check with your prescriber or pharmacist before taking them. And keep in mind that maintaining a healthy lifestyle, balanced diet, and washing your hands often during cold and flu season are the best ways to keep your immune system healthy.
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References
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