Last update
4/13/2026
Research Authors

Overview

SCIENTIFIC SCORE
Moderately Effective
Based on 2 Researches
8
USERS' SCORE
Moderately Good
Based on 451 Reviews
7.7
Supplement Facts
Serving Size: 1 VegCap
Amount Per Serving
%DV
Vitamin C (as Ascorbic Acid, Acerola Cherry, Rose Hips)
1,000 mg
1,111%
📅 Last updated:

Top Medical Research Studies

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
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

Most Useful Reviews

6
Prevention aid
188 people found this helpful
We use these both for prevention and during a cold. Personally, I find the tablets harder to swallow than the capsules.
Read More
5
Blood thinning effect
136 people found this helpful
An excellent option for colds, as it thins the blood. More than two capsules should not be consumed.
Read More
8
Immune support boost
105 people found this helpful
Take it, you won't regret it! This excellent quality vitamin has a sustained release, with half absorbed immediately and half entering the body over 12 hours. One capsule per day is standard, but during colds, you can take up to six capsules daily for the first few days to enhance immunity. Symptoms improve quickly, and I felt better by the second day without severe illness. It’s non-allergenic, which is a relief for someone like me who previously reacted to Russian vitamin C. This option is also significantly cheaper than what’s available locally. Please click "thumb up" if you find this useful!
Read More

Most Recommended Products for Cold

NOW Foods Calcium & Magnesium
SCIENTIFIC SCORE
Moderately Effective
Based on 4 Researches
8.8
USERS' SCORE
Excellent
Based on 15 Reviews
9
NOW Foods 5-HTP
SCIENTIFIC SCORE
Likely Very Effective
Based on 1 Research
9
USERS' SCORE
Good
Based on 6 Reviews
8.6
Solgar L-Lysine
SCIENTIFIC SCORE
Likely Very Effective
Based on 1 Research
9
USERS' SCORE
Good
Based on 30 Reviews
8.3
Source Naturals Magnesium Malate
SCIENTIFIC SCORE
Moderately Effective
Based on 4 Researches
8.8
USERS' SCORE
Good
Based on 5 Reviews
8.4

Medical Researches

SCIENTIFIC SCORE
Moderately Effective
Based on 2 Researches
8
  • All Researches
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
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
Moderately Good
Based on 451 Reviews
7.7
  • All Reviews
  • Positive Reviews
  • Negative Reviews
6
Prevention aid
188 people found this helpful
We use these both for prevention and during a cold. Personally, I find the tablets harder to swallow than the capsules.
Read More
5
Blood thinning effect
136 people found this helpful
An excellent option for colds, as it thins the blood. More than two capsules should not be consumed.
Read More
8
Immune support boost
105 people found this helpful
Take it, you won't regret it! This excellent quality vitamin has a sustained release, with half absorbed immediately and half entering the body over 12 hours. One capsule per day is standard, but during colds, you can take up to six capsules daily for the first few days to enhance immunity. Symptoms improve quickly, and I felt better by the second day without severe illness. It’s non-allergenic, which is a relief for someone like me who previously reacted to Russian vitamin C. This option is also significantly cheaper than what’s available locally. Please click "thumb up" if you find this useful!
Read More
8
Reduced colds occurrence
26 people found this helpful
With this product, I experience fewer colds. It is an effective vitamin C complex.
Read More
7
Quick recovery aid
26 people found this helpful
Excellent immune support from this high-quality vitamin. It truly helps me not to fall apart during colds and seasonal viruses, allowing for a speedy recovery. The product is of good quality and does not irritate the stomach. The medium-sized capsules are easy to swallow with water.
Read More

Frequently Asked Questions

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. Hemilä H, Chalker E. Vitamin C for the common cold and pneumonia. Pol Arch Intern Med. 2025;135. 10.20452/pamw.16926
  2. 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
image