Last update
5/29/2026
Research Authors

Overview

SCIENTIFIC SCORE
Moderately Effective
Based on 2 Researches
8
USERS' SCORE
Moderately Good
Based on 263 Reviews
7.8
Supplement Facts
Serving Size: 1 Vegetable Capsule
Amount Per Serving
%DV
Vitamin C
500 mg
556%
📅 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

8
Better vitamin choice
109 people found this helpful
For colds, I always take different types of vitamin C, and I preferred this one more.
Read More
7
Improved immune system
29 people found this helpful
I drink lots of vitamins during the autumn-winter period to maintain my immunity and overall health. Vitamin C is crucial; it comes in a dark glass jar with 100 capsules. I take 1 capsule after meals in the morning and evening for 2-3 months. I've become less ill with colds and no longer catch the flu from others. This vitamin also aids in the absorption of others that support my skin, hair, and nails. My general condition has improved, and I feel more energetic.
Read More
10
Beauty & cold support
15 people found this helpful
Compared to city pharmacies, this is much more affordable. Each capsule contains 500 mg of vitamin C, which is essential for beauty and youth as well as for supporting the immune system, particularly during the onset of a cold. Remarkably, my husband and I have not been seriously ill this winter.
Read More

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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 263 Reviews
7.8
  • All Reviews
  • Positive Reviews
  • Negative Reviews
8
Better vitamin choice
109 people found this helpful
For colds, I always take different types of vitamin C, and I preferred this one more.
Read More
7
Improved immune system
29 people found this helpful
I drink lots of vitamins during the autumn-winter period to maintain my immunity and overall health. Vitamin C is crucial; it comes in a dark glass jar with 100 capsules. I take 1 capsule after meals in the morning and evening for 2-3 months. I've become less ill with colds and no longer catch the flu from others. This vitamin also aids in the absorption of others that support my skin, hair, and nails. My general condition has improved, and I feel more energetic.
Read More
10
Beauty & cold support
15 people found this helpful
Compared to city pharmacies, this is much more affordable. Each capsule contains 500 mg of vitamin C, which is essential for beauty and youth as well as for supporting the immune system, particularly during the onset of a cold. Remarkably, my husband and I have not been seriously ill this winter.
Read More
8
Strengthens immune system
5 people found this helpful
During the autumn-winter months, I find vitamin C essential. It strengthens the immune system. I typically take it at the first hint of a cold, and after three days of taking 3-4 tablets daily, I usually feel better. This vitamin works well without negative effects on my digestive system.
Read More
9
Boosts health immediately
4 people found this helpful
I highly recommend it! Many reviews exist about vitamin C, and I can only affirm that it's extremely beneficial. If I sense I'm catching a cold, I take one capsule before bedtime, and by morning, I feel revitalised and healthy!
Read More

Frequently Asked Questions

8
Reversed malaise
1 people found this helpful
A great product! Vitamin C works well. I experienced slight malaise, as if a cold was coming, so I took 1000mg. By morning, the symptoms had disappeared. I'm incredibly grateful.
9
Prevents cold symptoms
I drink vitamin C from this company regularly, except in summer. It particularly helps when I feel the onset of a cold; I take a capsule every three hours, and the next day there are no signs of a cold.
10
Increased immunity
1 people found this helpful
Super Vitamin C has been part of my routine for nearly a month now. I haven’t fallen ill, especially during this cold season. It’s an excellent product for boosting immunity at a reasonable price. I highly recommend it.
9
Immunity increased
3 people found this helpful
Vitamin C should be in every home. My life has changed since I began taking vitamin C daily. I used to suffer from frequent colds and fatigue. Since I started regular intake, my immunity has improved, and I hardly catch colds now—just a few times, and lightly.
10
Forgot about colds
I take this vitamin twice a year to prevent respiratory infections and boost immunity. I take one capsule daily after breakfast for a month. The capsules are small and easy to swallow. After using this product, I forgot about colds, and it also helped with chronic fatigue.
9
Effective for cold
Excellent vitamin C. I consume it when I sense I'm becoming unwell. By the second day, the cold tends to dissipate. I also take it with iron for better absorption.
9
Instant support for colds
An effective product from Iherb, it helps instantly with colds. I take it alongside iron.
7
Effective for colds
Great vitamin with antioxidant protection. I took it for my husband with a cold. As prescribed by the doctor, take 1 capsule twice a day. After a week, we noticed results; the cold began to disappear, and his health improved significantly. The quality and effectiveness of the product is remarkable. I have since been giving vitamin C to my family. At the first sign of illness, I ensure we take vitamin C.
7
Family winter essential
An essential vitamin for winter; I ordered it for my large family again. We start taking it in October to adjust our bodies for winter. It's very effective. In summer, some may need to restore weakened immunity—it's better to take it in cold months.
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
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