Last update
3/25/2026
Research Authors

Overview

SCIENTIFIC SCORE
Moderately Effective
Based on 2 Researches
8
USERS' SCORE
Good
Based on 30 Reviews
8.1
Supplement Facts
Serving Size: 1 Packet (9.1 g)
Amount Per Serving
%DV
Calories
35
 
Total Carbohydrate
8 g
3%†
Total Sugars
6 g
*
Includes 6 g Added Sugars 
12 g†
Vitamin C (as ascorbic acid, zinc ascorbate)
1,000 mg
1,111%
Thiamin (as thiamine hydrochloride) (Vit.B1)
0.36 mg
30%
Riboflavin (as riboflavin-5¹-phosphate) (Vit. B2)
0.39 mg
30%
Niacin (Vit. B3)
4 mg
25%
Vitamin B6 (as pyridoxine hydrochloride)
10 mg
588%
Folate ( Vit. B9)
167 mcg DFE (100 mcg Folic Acid)
42%
Vitamin B12 (as cyanocobalamin)
25 mcg
1,042%
Pantothenic Acid (as calcium pantothenate) (Vit. B5)
2.5 mg
50%
Calcium (as calcium carbonate, monobasic calcium phosphate, tribasic calcium phosphate, calcium pantothenate)‡
50 mg
4%
Phosphorus (as monobasic potassium phosphate, monobasic calcium phosphate, monobasic sodium phosphate, tribasic calcium phosphate)‡
38 mg
3%
Magnesium (as magnesium hydroxide, magnesium carbonate)‡
53 mg
13%
Zinc (as zinc ascorbate)
2 mg
18%
Manganese (as manganese gluconate)
0.5 mg
22%
Zinc (as zinc ascorbate)
2 mg
18%
Manganese (as manganese gluconate)
0.5 mg
22%
Chromium (as chromium picolinate)
10 mcg
29%
Sodium (as sodium bicarbonate, monobasic sodium phosphate)‡
65 mg
3%
Potassium (as potassium bicarbonate, potassium carbonate, monobasic potassium phosphate)‡
200 mg
4%
📅 Last updated:

Top Medical Research Studies

8
Vitamin C aids flu symptom relief
We explored the impact of high doses of Vitamin C on cold and flu symptoms in a controlled study involving 752 students. While 463 participants made up the control group and received standard treatments, the 252 in the test group took 1000 mg of Vitamin C at set intervals.

After comparing reports from both groups, we observed that those who took Vitamin C experienced less severe and fewer symptoms compared to those who did not. This suggests that Vitamin C could be a helpful supplement in managing flu symptoms.
Read More
8
Vitamin C improves inflammatory response
We explored the effects of high-dose vitamin C on blood flow during inflammation caused by endotoxin. In a balanced, placebo-controlled crossover study with 36 male subjects, we examined how vitamin C administration impacted vascular function. After administering lipopolysaccharide (LPS), participants experienced flu-like symptoms and a significant drop in blood flow response.

However, we found that high-dose vitamin C improved this blood flow response, suggesting it can help counteract issues related to inflammation. This paves the way for further research on vitamin C's benefits in similar conditions.
Read More

Most Useful Reviews

10
Powerful punch
This is the only Vitamin C I take, especially during flu season. I have not had a cold or flu in years. I carry packs with me all the time, and it tastes good.
Read More
10
Immediate effects
I love this product. It takes cold and flu symptoms away immediately.
Read More
9
Effective treatment
We used this drink in the complex treatment of influenza as a primary source of vitamin C. The solution was pleasantly warm, solving two problems: a warm drink and vitamin C. I highly recommend it. All adult family members enjoyed it, and the pleasant taste adds to the experience.
Read More

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8.3

Medical Researches

SCIENTIFIC SCORE
Moderately Effective
Based on 2 Researches
8
  • All Researches
8
Vitamin C improves inflammatory response
We explored the effects of high-dose vitamin C on blood flow during inflammation caused by endotoxin. In a balanced, placebo-controlled crossover study with 36 male subjects, we examined how vitamin C administration impacted vascular function. After administering lipopolysaccharide (LPS), participants experienced flu-like symptoms and a significant drop in blood flow response.

However, we found that high-dose vitamin C improved this blood flow response, suggesting it can help counteract issues related to inflammation. This paves the way for further research on vitamin C's benefits in similar conditions.
Read More
8
Vitamin C aids flu symptom relief
We explored the impact of high doses of Vitamin C on cold and flu symptoms in a controlled study involving 752 students. While 463 participants made up the control group and received standard treatments, the 252 in the test group took 1000 mg of Vitamin C at set intervals.

After comparing reports from both groups, we observed that those who took Vitamin C experienced less severe and fewer symptoms compared to those who did not. This suggests that Vitamin C could be a helpful supplement in managing flu symptoms.
Read More

User Reviews

USERS' SCORE
Good
Based on 30 Reviews
8.1
  • All Reviews
  • Positive Reviews
  • Negative Reviews
10
Powerful punch
This is the only Vitamin C I take, especially during flu season. I have not had a cold or flu in years. I carry packs with me all the time, and it tastes good.
Read More
10
Immediate effects
I love this product. It takes cold and flu symptoms away immediately.
Read More
9
Effective treatment
We used this drink in the complex treatment of influenza as a primary source of vitamin C. The solution was pleasantly warm, solving two problems: a warm drink and vitamin C. I highly recommend it. All adult family members enjoyed it, and the pleasant taste adds to the experience.
Read More
9
High effectiveness
The quality is excellent, with ingredients suitable for influenza. The quantity is small compared to the price, but the immunity boost is high. It suited me better than what is available in pharmacies, is light on the stomach, and its effectiveness is outstanding.
Read More
9
Health benefits
The best of all! Very good for your immune system and skin, and helps keep you healthy while warding off colds and flu.
Read More

Frequently Asked Questions

9
Effective symptom relief
Helps with cold/flu symptoms. Take one immediately when feeling unwell, and symptoms will vanish by the next day!
9
Quick relief
Great whenever I feel as though a flu is about to overwhelm me, I take one. I feel better within minutes and have the energy to finish the day.
7.5
Prevents illness
Effective at keeping cold and flu at bay. Whenever I get a scratchy throat or feel tired, I take a sachet and it either kicks the cold away or lessens the effects. Good value for money and tastes good.
10
Immediate effects
I love this product. It takes cold and flu symptoms away immediately.
7.5
Quick recovery
The choice for mid-flu: after catching a cold, drinking it will help you recover quickly.
9
Effective treatment
We used this drink in the complex treatment of influenza as a primary source of vitamin C. The solution was pleasantly warm, solving two problems: a warm drink and vitamin C. I highly recommend it. All adult family members enjoyed it, and the pleasant taste adds to the experience.
6
Winter support
It’s good for the winter season— a great addition to my routine, especially during flu season. The 1000mg of Vitamin C per packet provides a noticeable energy boost and supports my immune system.
7
Easier absorption
Excellent! I believe effervescent vitamin C is absorbed and assimilated more easily than capsules. They also contain B vitamins and antioxidants. They taste pleasant and help keep flu at bay.
7.5
Immunity boost
Works wonders for improving my immunity. I have been using Emergen-C for quite a while now. It has always been helpful when I felt I might catch the flu but has also served as a daily supplement due to my low energy from hypothyroidism. I recommend it both as an immune booster and for an extra kick of energy.

References

  1. Aschauer S, Gouya G, Klickovic U, Storka A, Weisshaar S, et al. Effect of systemic high dose vitamin C therapy on forearm blood flow reactivity during endotoxemia in healthy human subjects. Vascul Pharmacol. 2014;61:25. 10.1016/j.vph.2014.01.007
  2. Gorton HC, Jarvis K. The effectiveness of vitamin C in preventing and relieving the symptoms of virus-induced respiratory infections. J Manipulative Physiol Ther. 1999;22:530. PubMed
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