Research Authors

Overview

SCIENTIFIC SCORE
Moderately Effective
Based on 4 Researches
8
USERS' SCORE
Good
Based on 169 Reviews
8.2
Supplement Facts
Serving Size: 1 Vegetarian Tablet
Amount Per Serving
%DV
Vitamin C (as Ester-C® Calcium Ascorbate)
1,000 mg (1 g)
1,111%
Calcium (as Ester-C® Calcium Ascorbate)
110 mg
8%
Citrus Bioflavonoids ComplexCitrus Bioflavonoids (Citrus sinensis) (fruit), Sweet Orange, Tangerine, Lime, Lemon, Acerola, Rutin, Hesperidin Complex (Citrus spp.) (fruit), Naturally Occurring Vitamin C Metabolites
200 mg
**

Top Medical Research Studies

9
Vitamin C reduces cold incidences
We investigated whether a daily vitamin C supplement could reduce the risk of catching colds. Over two months, 168 people took either the supplement or a placebo. Results showed that those taking vitamin C experienced significantly fewer colds and shorter durations of severe symptoms compared to the placebo group.

This supplement was well-tolerated with minimal side effects, and participants were notably satisfied with it. Overall, it seems that vitamin C may not only help prevent colds but also assist in faster recovery from them.
Read More
7
Vitamin C alleviates cold symptoms
We looked into how vitamin C affects cold symptoms through a well-structured study involving 622 volunteers divided into treatment groups. They received either vitamin C or a placebo over a 15-week period.

While both vitamin C groups experienced milder illnesses compared to the placebo group, there were no significant differences between the two forms of vitamin C used. Interestingly, those taking vitamin C spent about 25% fewer days sick indoors. This suggests that while vitamin C can alleviate some cold symptoms, we might not need as high a dose as previously thought.
Read More
7
Effectiveness of Vitamin C on Colds
We explored the effects of vitamin C on the common cold and pneumonia by examining a range of studies. Interestingly, research on animals suggests that vitamin C may have protective effects against infections. However, when it comes to preventing colds in the general population, taking more than 1 gram of vitamin C per day didn’t show significant benefits.

But there's a twist! Participants engaged in heavy physical activities saw their cold incidence reduced by half with vitamin C supplementation. Additionally, regular intake of 1 gram or more daily was linked to a 15% decrease in cold severity. While some therapeutic trials showed inconsistent results when vitamin C was taken after cold symptoms appeared, two studies did indicate that larger doses (6-8 grams per day) could effectively shorten the duration of colds compared to lower doses.

Our investigation also looked into pneumonia, but the studies were conducted in unique settings, such as a boarding school and military recruits. This makes it hard to generalize the findings to the wider population. Yet, some trials suggested benefits for pneumonia patients. Finally, the role of vitamin C in treating COVID-19 and sepsis remains unclear, with mixed results.

Given that vitamin C seems to alleviate symptoms and shorten the duration of colds, while being safe and affordable, it might be worth considering a dose of 6-8 grams per day to see if it helps at an individual level.
Read More

Most Useful Reviews

9
Effective cold remedy
133 people found this helpful
A super remedy for colds and Covid. I keep it in my first aid kit for everyone. In the initial days of a cold, I take 1 tablet three times a day for 3-5 days, then reduce the dose to 1 tablet daily for up to 14 days. It helped me cope with the illness.
Read More
9
Supports immune system
21 people found this helpful
I frequently use vitamin C during fall and winter. At the first sign of a cold, I take 1 capsule with zinc or elderberry, which often works, and I wake without any signs of illness. It’s suitable during illness too, helping my immune system fight the virus and preventing complications.
Read More
9
Rapid cold recovery
8 people found this helpful
I love this product—one of my best purchases! The bioflavonoids ensure better absorption. I take one capsule during a cold or when I feel unwell. It definitely works as colds go away quickly, even sore throats resolve in a day.
Read More

Medical Researches

SCIENTIFIC SCORE
Moderately Effective
Based on 4 Researches
8
  • All Researches
9
Vitamin C reduces cold incidences
We investigated whether a daily vitamin C supplement could reduce the risk of catching colds. Over two months, 168 people took either the supplement or a placebo. Results showed that those taking vitamin C experienced significantly fewer colds and shorter durations of severe symptoms compared to the placebo group.

This supplement was well-tolerated with minimal side effects, and participants were notably satisfied with it. Overall, it seems that vitamin C may not only help prevent colds but also assist in faster recovery from them.
Read More
9
Vitamin C improves cold tolerance
We explored the effects of ascorbic acid, commonly known as vitamin C, on cold tolerance in tomato seedlings. In our study, we discovered that applying vitamin C significantly boosts the seedlings' ability to handle cold stress.

By enhancing the antioxidant defense system, vitamin C treatment increased the enzyme activity in the seedlings' leaves. Additionally, it raised levels of important compounds such as proline, sugar, and abscisic acid, all of which play crucial roles in plant stress responses.

Our observations showed that vitamin C also protects the photosynthesis system of tomato seedlings. This implies that it helps maintain chlorophyll function, which is critical for the plant's overall health, especially under cold conditions.

Moreover, we found that vitamin C treatments led to increased expression of genes linked to antioxidant enzymes and cold response mechanisms. Overall, our findings suggest that exogenous vitamin C is a beneficial approach to improve cold tolerance in tomatoes and may provide helpful insights for farmers looking to cultivate hardier varieties during colder months.
Read More
7
Vitamin C alleviates cold symptoms
We looked into how vitamin C affects cold symptoms through a well-structured study involving 622 volunteers divided into treatment groups. They received either vitamin C or a placebo over a 15-week period.

While both vitamin C groups experienced milder illnesses compared to the placebo group, there were no significant differences between the two forms of vitamin C used. Interestingly, those taking vitamin C spent about 25% fewer days sick indoors. This suggests that while vitamin C can alleviate some cold symptoms, we might not need as high a dose as previously thought.
Read More
7
Effectiveness of Vitamin C on Colds
We explored the effects of vitamin C on the common cold and pneumonia by examining a range of studies. Interestingly, research on animals suggests that vitamin C may have protective effects against infections. However, when it comes to preventing colds in the general population, taking more than 1 gram of vitamin C per day didn’t show significant benefits.

But there's a twist! Participants engaged in heavy physical activities saw their cold incidence reduced by half with vitamin C supplementation. Additionally, regular intake of 1 gram or more daily was linked to a 15% decrease in cold severity. While some therapeutic trials showed inconsistent results when vitamin C was taken after cold symptoms appeared, two studies did indicate that larger doses (6-8 grams per day) could effectively shorten the duration of colds compared to lower doses.

Our investigation also looked into pneumonia, but the studies were conducted in unique settings, such as a boarding school and military recruits. This makes it hard to generalize the findings to the wider population. Yet, some trials suggested benefits for pneumonia patients. Finally, the role of vitamin C in treating COVID-19 and sepsis remains unclear, with mixed results.

Given that vitamin C seems to alleviate symptoms and shorten the duration of colds, while being safe and affordable, it might be worth considering a dose of 6-8 grams per day to see if it helps at an individual level.
Read More

User Reviews

USERS' SCORE
Good
Based on 169 Reviews
8.2
  • All Reviews
  • Positive Reviews
  • Negative Reviews
9
Effective cold remedy
133 people found this helpful
A super remedy for colds and Covid. I keep it in my first aid kit for everyone. In the initial days of a cold, I take 1 tablet three times a day for 3-5 days, then reduce the dose to 1 tablet daily for up to 14 days. It helped me cope with the illness.
Read More
9
Supports immune system
21 people found this helpful
I frequently use vitamin C during fall and winter. At the first sign of a cold, I take 1 capsule with zinc or elderberry, which often works, and I wake without any signs of illness. It’s suitable during illness too, helping my immune system fight the virus and preventing complications.
Read More
9
Rapid cold recovery
8 people found this helpful
I love this product—one of my best purchases! The bioflavonoids ensure better absorption. I take one capsule during a cold or when I feel unwell. It definitely works as colds go away quickly, even sore throats resolve in a day.
Read More
9
Strong antioxidant
6 people found this helpful
I’ve used vitamin C for a year, and it works! Recently, I fell ill with ARVI, and my vitamin C ran out at an inopportune moment. It strengthens cell resistance, gives energy, and promotes recovery. When I feel early signs of a cold, I take 1 tablet daily for three days, and all symptoms vanish. Remarkably effective!
Read More
10
Sos remedy for cold
3 people found this helpful
The 500 mg Non-Acidic Vitamin C with bioflavonoids is my go-to remedy at the first sign of a cold. It has a beneficial composition with no irritation to the stomach, and I take two capsules daily during early illness. This vitamin C helps raise my immunity, and I rarely fall ill.
Read More

Frequently Asked Questions

10
Cold eliminated quickly
Excellent! The cold was gone within two days.
9
Quick relief
1 people found this helpful
Best Vitamin C! I felt the benefit of regular use—my skin improved and my immunity peaked. Symptoms of a cold, like a sore throat and runny nose, disappeared within a day. It's the best form for absorption.
10
Cold relief
Excellent vitamin C that I will purchase again. When I feel a cold coming on, I took 4000 mg (4 tablets) at once, and the cold passed by evening! The tablets are large but easy to swallow, with no negative reactions.
10
Sos remedy for cold
3 people found this helpful
The 500 mg Non-Acidic Vitamin C with bioflavonoids is my go-to remedy at the first sign of a cold. It has a beneficial composition with no irritation to the stomach, and I take two capsules daily during early illness. This vitamin C helps raise my immunity, and I rarely fall ill.
9
Immunity booster
I can't afford to be without it. After five years of taking this vitamin C, I’ve hardly had a cold. I truly feel my immunity is strengthened, making it an indispensable supplement for me.
9
Supports immune system
21 people found this helpful
I frequently use vitamin C during fall and winter. At the first sign of a cold, I take 1 capsule with zinc or elderberry, which often works, and I wake without any signs of illness. It’s suitable during illness too, helping my immune system fight the virus and preventing complications.
9
Effective C treatment
If I experience signs of a cold or illness, I take this vitamin C and zinc, drink plenty of fluids, and sleep, and by morning, I feel fine. This vitamin C form is effective and well absorbed due to the addition of bioflavonoids. I suggest everyone keep it in their medicine cabinet.
9
Prevents cold
I find it pointless to discuss the benefits of vitamin C since it’s a household staple. Recently, when I fell ill, I was relieved to have it on hand, taking it every two hours alongside vitamin D and zinc. Consequently, my cold did not worsen, and I’m now in excellent health. I regularly take it and strongly recommend it.
9
Vitamin C reduces cold incidences
We investigated whether a daily vitamin C supplement could reduce the risk of catching colds. Over two months, 168 people took either the supplement or a placebo. Results showed that those taking vitamin C experienced significantly fewer colds and shorter durations of severe symptoms compared to the placebo group.

This supplement was well-tolerated with minimal side effects, and participants were notably satisfied with it. Overall, it seems that vitamin C may not only help prevent colds but also assist in faster recovery from them.
7
Vitamin C alleviates cold symptoms
We looked into how vitamin C affects cold symptoms through a well-structured study involving 622 volunteers divided into treatment groups. They received either vitamin C or a placebo over a 15-week period.

While both vitamin C groups experienced milder illnesses compared to the placebo group, there were no significant differences between the two forms of vitamin C used. Interestingly, those taking vitamin C spent about 25% fewer days sick indoors. This suggests that while vitamin C can alleviate some cold symptoms, we might not need as high a dose as previously thought.
7
Effectiveness of Vitamin C on Colds
We explored the effects of vitamin C on the common cold and pneumonia by examining a range of studies. Interestingly, research on animals suggests that vitamin C may have protective effects against infections. However, when it comes to preventing colds in the general population, taking more than 1 gram of vitamin C per day didn’t show significant benefits.

But there's a twist! Participants engaged in heavy physical activities saw their cold incidence reduced by half with vitamin C supplementation. Additionally, regular intake of 1 gram or more daily was linked to a 15% decrease in cold severity. While some therapeutic trials showed inconsistent results when vitamin C was taken after cold symptoms appeared, two studies did indicate that larger doses (6-8 grams per day) could effectively shorten the duration of colds compared to lower doses.

Our investigation also looked into pneumonia, but the studies were conducted in unique settings, such as a boarding school and military recruits. This makes it hard to generalize the findings to the wider population. Yet, some trials suggested benefits for pneumonia patients. Finally, the role of vitamin C in treating COVID-19 and sepsis remains unclear, with mixed results.

Given that vitamin C seems to alleviate symptoms and shorten the duration of colds, while being safe and affordable, it might be worth considering a dose of 6-8 grams per day to see if it helps at an individual level.

References

  1. Van Straten M, Josling P. Preventing the common cold with a vitamin C supplement: a double-blind, placebo-controlled survey. Adv Ther. 2002;19:151.
  2. Anderson TW, Beaton GH, Corey P, Spero L. Winter illness and vitamin C: the effect of relatively low doses. Can Med Assoc J. 1975;112:823.
  3. Hemilä H, Chalker E. Vitamin C for the common cold and pneumonia. Pol Arch Intern Med. 2025;135. 10.20452/pamw.16926
  4. Wang X, Ran C, Fu Y, Han L, Yang X, et al. Application of Exogenous Ascorbic Acid Enhances Cold Tolerance in Tomato Seedlings through Molecular and Physiological Responses. Int J Mol Sci. 2024;25. 10.3390/ijms251810093
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