Before I had my son, I would get sick twice a year and it was no big deal. Surprise, surprise: It’s a lot easier to avoid the common cold when you don’t have a germy toddler coughing in your mouth. Nowadays, little stands between a new virus and me, and as such, drinking Emergen-C and obsessive hand washing have become my weapons of choice.
Each time I mix the effervescent orange powder into my water (I prefer it to the chewables or gummies), I’m filled with a glass-half-full kind of attitude. Emergen-C makes me feel proactive—not to mention efficient. I would never dream of consuming 10 oranges in a single day, and yet that’s apparently the amount of vitamin C in *one* packet of Emergen-C.
In addition to containing 1,000 milligrams of vitamin C (the recommended daily dose for adults is anywhere from 75 to 90 milligrams, according to the National Institutes of Health), the supplement is full of B vitamins and antioxidants which the brand’s website claims support the immune system while enhancing energy levels. But can Emergen-C really keep sickness at bay? Or is it just another case of clever marketing forces at work?
First, let's look at the ingredients in Emergen-C.
The main ingredients advertised in Emergen-C and many immune-supporting supplements are vitamin C and zinc. What I believed was the obvious draw with Emergen-C (or any immune booster like this kind, including Airborne, or Nuun immunity tablets) was the vitamin C for cold prevention. But while vitamin C has the reputation of being a savior if you're getting or already have a cold, there isn't actually much scientific evidence to back either of those claims up.
Emergen-C Daily Immune Support Drink
It's true that vitamins, including vitamin C, are crucial for our daily functioning and are healthy to consume. But if you already have a cold, it won't actually help shorten the duration of a cold very much (no cure exists for the common cold!)—maybe a day, tops, according to Harvard Health.
“Emergen-C is a vitamin C supplement, and there’s no evidence that it benefits people with the cold or influenza or [that it] affects your propensity to get the cold or the flu,” says Amesh Adalja, MD, an infectious disease physician and a senior scholar at the Johns Hopkins Center for Health Security. The same goes for a respiratory virus like the novel coronavirus, or COVID-19.
Dr. Adalja adds that it’s misguided to think that vitamin C is a panacea for respiratory viruses. Supplements aren’t evaluated by the FDA, and he worries that if people depend too much on vitamin C supplements or believe they will cure a cold or flu, it could steer people away from the number one preventive measure: the flu vaccine.
What about the other biggie ingredient zinc, you're wondering? “Study results are mixed, but the short answer is that zinc probably doesn’t prevent or treat a cold,” Tina Ardon, MD, a family medicine doctor at Mayo Clinic in Jacksonville, Florida, previously told WH. There’s very limited evidence that zinc may help shorten a cold but only by a day or so as well, and you have to start taking it right at the onset of symptoms.
Unfortunately, there’s no vaccine or magic fix for the common cold because it’s caused by a host of viruses. Practicing good hygiene and getting ample sleep are your best bets to kick a cold—and even then there are no guarantees, according to Dr. Adalja. Once you’re sick, however, there are over-the-counter medications like Dayquil and Nyquil that can help mediate your symptoms, he points out.
Another thing: Emergen-C isn’t as effective if it’s expired.
Remember, there is no evidence that Emergen-C, or any other immune booster that combines vitamins and minerals, is an effective treatment for a cold, flu, or infectious viral illness (think: COVID-19), according to Frederick Hecht, MD, professor of medicine at University of California, San Francisco. The vitamins, minerals, and antioxidants in Emergen-C can be easily obtained in a healthy diet that includes fruits and vegetables, he says. "And whole foods are likely to have other health benefits that can’t easily be extracted into a small packet of powder," Dr. Hecht says.
But if you are going to use Emergen-C to give your immune system a helping hand, make sure to check the expiration date first—especially if it's been sitting in that medicine cabinet for a bit. While vitamins and minerals do not pose health risks if they are outdated, some of them may deteriorate over time—"which means that you will not get the full amount of vitamin labeled on the package," Dr. Hecht says.
You don't have to stop taking vitamin C or other immune-supporting supps if you enjoy the ritual of it, though.
Most Americans are vitamin C replete, meaning they're already well-supplied with it for the most part via their diet, "so giving them extra vitamin C isn’t going to have any benefits,” explains Dr. Adalja. Vitamin C is water-soluble, so excess of the vitamin doesn't get stored in the body and will be flushed out via your pee. This means that you won't harm yourself by taking more vitamin C than you need.
Indeed, the only time he would promote the use of a vitamin C supplement for the average American is if they ate hardly any fruits or veggies and were at risk of becoming deficient in a key vitamin (and you'd really only know this for sure via a workup from your doctor).
But on the fizzy orange bright side: Dr. Adalja says there’s no harm in taking Emergen-C or other vitamin C/immunity supplements. Although supplements in general are not regulated by the FDA, as mentioned, so-called immune-boosting supplements with these ingredients generally don't come with side effects. The caveat: If you overdo it on zinc in particular, it may lead to anemia or nervous-system damage, WH reported previously. So be sure to stick to the recommended serving size for these cold supps.
Ultimately, if it makes you happy to ingest a vitamin C immune-supporting supplement like Emergen-C, you feel like you're doing something good for your body, you're sticking to a serving size, and you're still getting your flu vaccine each year, there’s no need to kick your habit. After all, there’s something to be said for adding a daily dose of optimism to your diet when you're feeling under the weather.
Just make sure that you're also keeping up with other best practices for good hygiene and never (!!) underestimate the value of washing your hands.
