Does Emergen-C Work? A Look at the Benefits and Side Effects

You can take one Emergen-C packet daily to potentially decrease the duration and severity of your cold.
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Emergen-C — a powder supplement that contains high doses of certain nutrients like vitamin C – is popular for its supposed cold-fighting and immune-supporting benefits. But does Emergen-C really work?


Here's everything you need to know about the supplement, including its benefits, side effects and whether it's good for kids.

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What Is Emergen-C?

Emergen-C is a powdered drink mix that contains large doses of certain vitamins and minerals that people often take when sick with a cold or flu to relieve symptoms and shorten the duration of the illness, per UC San Diego.

Emergen-C's purported immune perks come from the high doses of vitamin C, vitamin B6 and vitamin B12 in particular — one packet of the drink powder contains about 1,111 percent, 588 percent and 1,042 percent of your recommended daily value of each nutrient, respectively.

Given those high amounts, how many Emergen-C packets should you take in a day? The company recommends a dosage of one packet daily, so you should avoid drinking the supplement more often than that. Just follow the instructions on the label to start sipping: Pour the powder into a 4- to 6-ounce glass of water, stir and then drink the resulting fizzy concoction.


So, what's in Emergen-C? Here's a list of the nutrition facts and ingredients for a single serving of the original immune-support formula in orange flavor, which is recommended for people ages 14 and older, according to Emergen-C:

  • Calories:‌ 35
  • Total carbs:‌ 8 g
    • Sugar:‌ 6 g
  • Vitamin C:‌ 1,000 mg
  • Thiamin:‌ 0.36 mg
  • Riboflavin:‌ 0.39 mg
  • Niacin:‌ 4 mg
  • Vitamin B6:‌ 10 mg
  • Vitamin B12:‌ 25 mcg
  • Calcium:‌ 50 mg
  • Magnesium:‌ 53 mg
  • Zinc:‌ 2 mg


The nutrition facts in other immune-support flavors like pink lemonade or cranberry-pomegranate may vary slightly. There are also alternative Emergen-C products that contain different ingredients, including:

  • Enhanced immune-support formula with extra vitamin D and zinc
  • Botanical drink powders with turmeric, ginger or elderberry
  • Probiotic powders with bacterial strains
  • Blueberry-açai energy shots with caffeine
  • Hydration powders with added electrolytes like potassium
  • Sleep powder with melatonin
  • "Kidz" powder with a smaller dose of vitamins and minerals for children




Though taking too much vitamin C is unlikely to harm you, the Mayo Clinic recommends adults stick to an upper limit of 2,000 milligrams per day.

Emergen-C Benefits

So, is Emergen-C good for you? Turns out the drink may have benefits when it comes to the common cold and beyond.

Here are the things Emergen-C may do to support your health.

1. It May Shorten Colds

Vitamin C may decrease the severity of symptoms and the duration of your cold, per the U.S. National Library of Medicine (NLM). However, it's important to note that vitamin C won't prevent a cold in the first place.


When it comes to supplements like Emergen-C specifically, the jury is still out, per a February 2016 review in the ‌American Journal of Lifestyle Medicine‌. Though vitamin C can indeed help shorten colds, you can probably get enough of the nutrient through your diet. That said, the review notes that it's OK to give vitamin C supplements a go if you've got the sniffles, as they're largely considered safe even if they don't always produce the desired effects.


But vitamin C isn't the only potential cold-fighting ingredient in Emergen-C: Zinc may also help shorten the duration of your cold, per the National Center for Complementary and Integrative Health (NCCIH).

Is There a Best Time of Day to Drink Emergen-C?

While there's no specific time of day you should drink Emergen-C, it may be best to take vitamin C within the first 24 hours of noticing cold symptoms, per the ‌American Journal of Lifestyle Medicine ‌review. The same goes for zinc, per the NCCIH.

The research also suggests that you should continue taking vitamin C for at least five days after symptoms start to reap the most benefits.

2. It May Support Immune Function

Getting enough vitamin C and vitamin B6 is crucial for healthy immune system function so your body can fight off disease as best as possible, according to the Cleveland Clinic. Emergen-C supplies a hefty dose of each, which is why it may help support immunity.


That said, it's best to get these vitamins through your diet, per the Cleveland Clinic, rather than only relying on supplements like Emergen-C.


Sources of Vitamins C and B6

Foods rich in vitamin C include:

  • Berries
  • Citrus fruits like oranges and grapefruit
  • Bell peppers
  • Broccoli
  • Brussels sprouts

Good sources of vitamin B6 include:

  • Salmon
  • Potatoes and sweet potatoes
  • Fortified tofu
  • Bananas

3. It Might Give You More Energy

Those B vitamins may also help increase your energy level. Why? The nutrient plays an important role in your body's energy production, so taking a supplement may combat fatigue, particularly for people with a vitamin B deficiency, per a January 2020 review in ‌Nutrients.

4. It Can Replenish Electrolytes

If you're sick with a flu, have diarrhea or work out extensively and sweat a lot, you'll lose electrolytes, which are minerals that keep you hydrated and help your heart, muscles and nerves function, per the NLM.

A serving of Emergen-C (particularly the hydration formula) may help replenish electrolytes like sodium, potassium and magnesium to prevent symptoms of dehydration and low electrolyte levels, such as muscle cramping or lightheadedness.

Does Emergen-C Work for Weight Loss?

There's no research to suggest that Emergen-C can help you lose weight. Instead, eating a balanced diet that includes enough vitamin C and other important nutrients to fuel your body (like protein, good carbs and fats) can help you find a healthy weight, per the Centers for Disease Control and Prevention.

Is Emergen-C Good for Kids?

While most adults can handle up to 2,000 milligrams of vitamin C per day, the Office of Dietary Supplements recommends that kids limit their intake to the below daily amounts to avoid potential side effects:

  • Birth to 1 year old:‌ Not established
  • 1 to 3 years old:‌ 400 mg
  • 4 to 8 years old:‌ 650 mg
  • 9 to 13 years old:‌ 1,200 mg
  • 14 to 18 years old:‌ 1,800 mg

Accordingly, one serving of the original Emergen-C formula may pack too much vitamin C for kids under 9 years old. Luckily, there's a drink power for children: Emergen-C Kidz, which contains 250 milligrams of vitamin C, per Emergen-C.

The nutrition label recommends children ages 4 to 13 drink one packet daily mixed into 4 to 6 ounces of water. The product is not suggested for kids younger than that.


Emergen-C Side Effects and Safety

Emergen-C isn't bad for you, but you may experience side effects like nausea if you take too much vitamin C.
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While Emergen-C and other high doses of vitamin C are generally considered good to try for colds (as long as you mind the upper limit of daily vitamin C intake recommended for your age group), there are still certain side effects to be aware of.

Per the Mayo Clinic, taking too much vitamin C from a supplement like Emergen-C may cause the following symptoms:

  • Upset stomach
  • Belly cramping
  • Bloating
  • Diarrhea
  • Heartburn
  • Headache
  • Fatigue

According to the Mayo Clinic, high doses of vitamin C like those in Emergen-C may also interact with certain medications, including:

  • Certain medications for high cholesterol, called statins
  • Warfarin, a blood-thinning medication
  • Certain types of HIV drugs called protease inhibitors
  • Oral contraceptives or hormone replacement therapy
  • Certain chemotherapy drugs
  • Certain medications for kidney disease that contain aluminum, called phosphate binders

And remember, the FDA does not require supplements like Emergen-C to be proven safe or effective before they are sold, so there's no guarantee that any supplement you take is safe, contains the ingredients it says it does or works the way it claims.


Talk to your doctor before trying Emergen-C if you have kidney problems, as high doses of vitamin C may be difficult for your kidneys to process, per the National Kidney Foundation.