We explored how vitamin C affects the severity of common colds through a comprehensive review of available studies. By including only randomized, placebo-controlled trials where participants received at least 1 gram of vitamin C daily, we aimed to investigate both the overall duration of colds and the intensity of symptoms experienced.
Our analysis found that vitamin C significantly reduced the severity of cold symptoms by about 15%. Interestingly, it appears that the benefits are more pronounced for those experiencing severe symptoms compared to mild ones. In specific comparisons, vitamin C didn’t substantially affect the duration of mild symptoms but had a notable impact on how long severe symptoms lasted.
This insight is crucial, as the common cold often leads to absenteeism at work and school, with more severe symptoms playing a key role in this setback. By highlighting vitamin C's greater effectiveness against intense cold symptoms, we suggest that future research should continue to look into how this vitamin can be utilized in managing cold severity.
Read More
8
Vitamin C's potential benefits highlighted
Bias against Vitamin C in Mainstream Medicine: Examples from Trials of Vitamin C for Infections.
We assessed the longstanding debate about vitamin C’s effectiveness in treating the common cold. This exploration reveals that evidence has consistently indicated that vitamin C can indeed help reduce the duration and severity of cold symptoms in certain circumstances.
However, despite this evidence, mainstream medicine has often favored what we call eminence-based medicine, relying on influential figures rather than empirical data. The skepticism surrounding vitamin C largely traces back to three pivotal studies published in 1975, two in JAMA and one in the American Journal of Medicine. These studies have shaped the narrative in textbooks and nutritional guidelines, despite exhibiting notable flaws that we carefully examined.
Furthermore, we highlighted misleading reporting in recent randomized trials and critical editorials published in JAMA regarding vitamin C. While our critique largely focuses on this journal, it reflects a broader trend across medical literature, indicating a possible bias against acknowledging the benefits of vitamin C in fighting colds.
Read More
8
Vitamin C reduces cold incidence
Vitamin C supplementation reduces the odds of developing a common cold in Republic of Korea Army recruits: randomised controlled trial.
We conducted an insightful study to explore whether vitamin C supplementation can help reduce the incidence of common colds among Republic of Korea Army recruits. Our research involved a rigorous randomised, placebo-controlled trial that included 1,444 soldiers over a 30-day period.
In this study, we divided the participants into two groups: one received a daily dose of 6,000 mg of vitamin C while the other received a placebo with no vitamin C. We investigated the soldiers' medical records to see how many of them contracted a cold during the training period.
Our findings showed encouraging results. The group that took vitamin C had a 20% lower risk of developing a common cold compared to those who took the placebo. Interestingly, this protective effect was especially pronounced among recruits in certain training camps, as well as never smokers and those who were physically ranked at level three.
Overall, we observed that vitamin C supplementation appears to be an effective strategy for reducing the incidence of common colds in military settings, which may lead to considerations for implementing vitamin C provisions during basic training for soldiers.
Read More
Most Useful Reviews
9
Prevents common cold
295 people found this helpful
Vitamin C from iHerb has been part of my first aid kit for three years, and I've purchased it five times. I typically take 3000-4000 mg at the first signs of a common cold, which usually stops it from developing. I now take one 500 mg tablet daily, as I have iron deficiency anaemia. The packaging is convenient, and the vitamins are easy to swallow. However, it’s crucial to monitor blood thickness when taking vitamin C.
Read More
9
Fast recovery
9 people found this helpful
Excellent vitamin C in an easy-to-manage dosage. I can adjust the dose by splitting the tablet. For common cold symptoms, my family takes a specific regimen that helps us recover quickly. We all benefit from it, including my parents.
Read More
9
Strengthens immunity
8 people found this helpful
This vitamin is essential now, particularly for combating viruses. The Now company offers a fantastic product at a good price. My family takes it regularly, and during a common cold, I increase my intake without concern, although I've noticed a tendency for heartburn over time. I began taking two tablets daily when I caught the flu, and I felt better in under a week.
We explored the potential benefits of vitamin C as a supplementary treatment for relieving common cold symptoms. By analyzing data from 10 randomized controlled trials, all focused on patients in China, we sought to understand how combining vitamin C with antiviral therapy might enhance recovery.
Our findings revealed that vitamin C supplementation could significantly improve overall efficacy, with a reported relative risk of 1.27. Moreover, it was shown to shorten the time it takes for symptoms to get better and for patients to heal, compared to antiviral therapy alone.
While vitamin C seems to have a positive impact when paired with antiviral drugs, it’s essential to note that its individual effects might not be fully clear due to the combined treatment approach used in the studies. Nonetheless, vitamin C presents itself as a promising addition to traditional cold treatments, helping patients manage their symptoms more effectively.
Read More
8
Vitamin C reduces cold severity
Vitamin C reduces the severity of common colds: a meta-analysis.
We explored how vitamin C affects the severity of common colds through a comprehensive review of available studies. By including only randomized, placebo-controlled trials where participants received at least 1 gram of vitamin C daily, we aimed to investigate both the overall duration of colds and the intensity of symptoms experienced.
Our analysis found that vitamin C significantly reduced the severity of cold symptoms by about 15%. Interestingly, it appears that the benefits are more pronounced for those experiencing severe symptoms compared to mild ones. In specific comparisons, vitamin C didn’t substantially affect the duration of mild symptoms but had a notable impact on how long severe symptoms lasted.
This insight is crucial, as the common cold often leads to absenteeism at work and school, with more severe symptoms playing a key role in this setback. By highlighting vitamin C's greater effectiveness against intense cold symptoms, we suggest that future research should continue to look into how this vitamin can be utilized in managing cold severity.
Read More
8
Vitamin C's potential benefits highlighted
Bias against Vitamin C in Mainstream Medicine: Examples from Trials of Vitamin C for Infections.
We assessed the longstanding debate about vitamin C’s effectiveness in treating the common cold. This exploration reveals that evidence has consistently indicated that vitamin C can indeed help reduce the duration and severity of cold symptoms in certain circumstances.
However, despite this evidence, mainstream medicine has often favored what we call eminence-based medicine, relying on influential figures rather than empirical data. The skepticism surrounding vitamin C largely traces back to three pivotal studies published in 1975, two in JAMA and one in the American Journal of Medicine. These studies have shaped the narrative in textbooks and nutritional guidelines, despite exhibiting notable flaws that we carefully examined.
Furthermore, we highlighted misleading reporting in recent randomized trials and critical editorials published in JAMA regarding vitamin C. While our critique largely focuses on this journal, it reflects a broader trend across medical literature, indicating a possible bias against acknowledging the benefits of vitamin C in fighting colds.
Read More
8
Vitamin C reduces cold incidence
Vitamin C supplementation reduces the odds of developing a common cold in Republic of Korea Army recruits: randomised controlled trial.
We conducted an insightful study to explore whether vitamin C supplementation can help reduce the incidence of common colds among Republic of Korea Army recruits. Our research involved a rigorous randomised, placebo-controlled trial that included 1,444 soldiers over a 30-day period.
In this study, we divided the participants into two groups: one received a daily dose of 6,000 mg of vitamin C while the other received a placebo with no vitamin C. We investigated the soldiers' medical records to see how many of them contracted a cold during the training period.
Our findings showed encouraging results. The group that took vitamin C had a 20% lower risk of developing a common cold compared to those who took the placebo. Interestingly, this protective effect was especially pronounced among recruits in certain training camps, as well as never smokers and those who were physically ranked at level three.
Overall, we observed that vitamin C supplementation appears to be an effective strategy for reducing the incidence of common colds in military settings, which may lead to considerations for implementing vitamin C provisions during basic training for soldiers.
We investigated how vitamin C affects the common cold, focusing on its potential for prevention and treatment. Research indicates that while vitamin C does not prevent colds in the general population when taken at doses over 1 g/day, it has been beneficial for individuals engaging in heavy physical activity, effectively halving their incidence of colds.
Looking into regular supplementation, we found that taking 1 g or more daily can reduce the severity of colds by about 15%. However, when it comes to starting vitamin C after cold symptoms begin, results are less consistent, though higher doses of 6-8 g/day did significantly shorten the duration of colds compared to lower doses.
Interestingly, historical studies showed that vitamin C might prevent pneumonia in specific populations, such as schoolboys or soldiers, but this doesn’t translate to the general public. While some trials indicated potential benefits for pneumonia patients, the evidence is not conclusive.
Overall, we see that given the evidence supporting reduced severity and duration of colds, along with its safety and affordability, it may be worth considering a higher dose of vitamin C for those looking to manage cold symptoms better.
Vitamin C from iHerb has been part of my first aid kit for three years, and I've purchased it five times. I typically take 3000-4000 mg at the first signs of a common cold, which usually stops it from developing. I now take one 500 mg tablet daily, as I have iron deficiency anaemia. The packaging is convenient, and the vitamins are easy to swallow. However, it’s crucial to monitor blood thickness when taking vitamin C.
Read More
9
Fast recovery
9 people found this helpful
Excellent vitamin C in an easy-to-manage dosage. I can adjust the dose by splitting the tablet. For common cold symptoms, my family takes a specific regimen that helps us recover quickly. We all benefit from it, including my parents.
Read More
9
Strengthens immunity
8 people found this helpful
This vitamin is essential now, particularly for combating viruses. The Now company offers a fantastic product at a good price. My family takes it regularly, and during a common cold, I increase my intake without concern, although I've noticed a tendency for heartburn over time. I began taking two tablets daily when I caught the flu, and I felt better in under a week.
Read More
9
Helps during colds
7 people found this helpful
Just a wonderful vitamin C. I drink it during a common cold, and it helps a lot!
Read More
9
Effective against viruses
7 people found this helpful
I recommend this product. I've ordered Vitamin C from this company for years and I'm very happy. It's especially beneficial for adults and children during virus season. If I feel unwell, I take 4 tablets a day along with other vitamins. It’s my go-to for common colds!
The common cold is a viral infection of the upper respiratory tract, primarily affecting the nose and throat. It's caused by a variety of viruses, with rhinoviruses being the most prevalent. Symptoms generally include a runny or stuffy nose, sore throat, cough, sneezing, mild headache, and sometimes a low-grade fever. While the common cold is often mild and resolves on its own within a week or two, it can still be bothersome and impact daily activities.
Transmission occurs through respiratory droplets when an infected person coughs or sneezes, or by touching surfaces contaminated with the virus. Preventative measures include frequent handwashing, using hand sanitizer, and avoiding close contact with infected individuals. Since there is currently no cure for the common cold, treatment focuses on symptom relief through over-the-counter medications, adequate rest, and hydration. While colds may be uncomfortable, they are generally not serious; however, seeking medical attention may be necessary if symptoms worsen or persist for an extended period.
Vitamin C, also known as ascorbic acid, is a water-soluble vitamin that plays a critical role in numerous bodily functions. As an essential nutrient, it contributes to the growth and repair of tissues in the body, and it is vital for the production of collagen, an important protein that helps maintain skin, cartilage, tendons, ligaments, and blood vessels. Additionally, Vitamin C acts as a powerful antioxidant, which means it helps combat free radicals—unstable molecules that can cause oxidative stress and contribute to various chronic diseases.
Moreover, Vitamin C enhances iron absorption from plant-based foods, making it a vital component for those following vegetarian or vegan diets. While many people get sufficient Vitamin C from a well-balanced diet that includes fruits and vegetables like oranges, strawberries, kiwi, broccoli, and bell peppers, some individuals might require supplementation. It's generally recommended to stay within the daily intake guidelines, as excessive consumption can lead to gastrointestinal disturbances. Overall, Vitamin C is not just a skincare celebrity—it's a fundamental part of maintaining overall health and well-being.
Vitamin C has long been touted as a remedy for the common cold, but the evidence supporting its efficacy is mixed. Some studies suggest that regular consumption of Vitamin C may reduce the duration and severity of cold symptoms, particularly in individuals who engage in intense physical activity or have a deficiency in this vitamin. However, for the average person, taking Vitamin C after the onset of cold symptoms is generally not shown to have a significant impact on shortening the cold.
If you're considering using Vitamin C to fend off colds, incorporating it into your daily routine through fruits and vegetables, such as oranges, strawberries, and bell peppers, can support overall immune function. Supplements might be beneficial for those who struggle to get enough from their diet, but they are not a guaranteed cure. While Vitamin C isn't a magic bullet against the common cold, maintaining adequate levels can contribute to overall health and may help mitigate some symptoms. However, always consult with a healthcare provider before starting any new supplement regimens.
According to user reviews, the timeline for seeing results from Vitamin C supplementation in combating the common cold varies. Many users indicate that they typically experience relief from symptoms or a halt to the cold's progression within hours to a few days after increasing their intake. For instance, one reviewer reports, "Whenever I or a family member feels a sore throat approaching a common cold, we take a Now C-500. Within hours, the pain subsides" Read Review. Another user noted feeling better in under a week after upping their dosage during an illness Read Review.
It appears that many users find initial benefits when they take the supplement at the first signs of a cold, with some noticing that increasing their dose can help them recover more quickly. For example, a reviewer mentions taking two pills at the first signs of illness, stating, "Most times, this stops the common cold before it starts" Read Review. Overall, users seem to experience noticeable effects quite swiftly, generally within a few days of increased usage.
Scientific research offers compelling evidence regarding the role of vitamin C in addressing common cold symptoms. Multiple studies confirm that while vitamin C does not prevent colds for the general population, regular supplementation can reduce the severity and duration of cold symptoms by approximately 15% for those taking doses of 1 gram or more daily ([1]). Notably, higher doses of vitamin C, notably between 6-8 g/day, have demonstrated a significant reduction in the duration of colds when administered at the onset of symptoms.
Moreover, a focused study on South Korean soldiers found that those who consumed a daily dose of 6,000 mg of vitamin C exhibited a 20% lower incidence of colds compared to a placebo group, particularly among physically demanding groups within the military ([7]). Thus, while vitamin C may not eliminate the risk of catching a cold, it shows promise in alleviating symptoms and mitigating the impact of cold-related illnesses, particularly in specific groups like heavy exercisers or those under environmental stress ([4]). With its safety profile and affordability, vitamin C is certainly worth considering for those looking to manage their cold symptoms effectively.
Users have reported a variety of improvements in symptoms related to the common cold after using Vitamin C supplements. Many reviewers highlight the preventive benefits of the vitamin, stating that it helps stop colds from developing when taken at the first signs of illness. For example, one user mentioned, "Whenever I or a family member feels a sore throat approaching a common cold, we take a Now C-500. Within hours, the pain subsides" Read Review. Other reviewers echoed similar sentiments, discussing rapid symptom relief and overall strengthening of their immune response, describing fewer instances of falling ill during cold and flu season Read Review.
Several users also reported increased dosage during illness, leading to a quicker recovery. One reviewer described taking "two pills at the first signs of illness," stating that this method often prevents the cold from developing Read Review. Overall, anecdotal evidence suggests that Vitamin C supplementation may provide significant immune support and symptom management for various users, although individual results can certainly vary based on personal health and circumstances.
Users have reported positive experiences when combining this Vitamin C supplement with other vitamins to manage common cold symptoms. Many families, for example, have a specific regimen that includes increasing their Vitamin C intake alongside other nutrients when they feel cold symptoms beginning. One reviewer mentioned, "We take one tablet for prevention daily and can increase to four if anyone feels unwell," showcasing a flexible approach to dosage in conjunction with other supplements Read Review. This evidence suggests that users perceive enhanced benefits by doiItng so, as they report quicker recovery times and symptom alleviation when they adjust their dosage during illness or combine it with alternative vitamins.
Moreover, several users have noted that they experience fewer colds by regularly supplementing with Vitamin C and any additional vitamins during the cold season. For instance, a reviewer stated they typically take 4 tablets a day along with other vitamins when feeling ill, which they found effective in combating cold symptoms Read Review. This trend of increased dosages during symptom onset, coupled with other supportive vitamins, appears to empower users in handling common colds more effectively.
Research indicates that when it comes to managing cold symptoms, higher doses of vitamin C may be particularly effective. Taking 1,000 mg (1 g) or more daily has been shown to reduce the severity of cold symptoms by about 15%. For individuals experiencing the most severe symptoms, vitamin C may prove particularly beneficial, as it has been found to have a more pronounced effect in these cases. Interestingly, when looking at the timing of supplementation, administering higher doses of 6,000 to 8,000 mg daily after the onset of cold symptoms does significantly shorten the duration of the illness compared to lower doses [1].
In military settings, a study showed that daily supplementation with 6,000 mg of vitamin C led to a 20% reduction in the incidence of colds among recruits. This suggests that for those under physical stress, higher doses of vitamin C could be a beneficial preventive strategy. Although the general public may not see the same level of incidence reduction, the potential to reduce the severity and duration of cold symptoms with appropriate dosages should not be overlooked [7]. Overall, while vitamin C is not a cure-all, it can be a cost-effective and safe option for improving cold symptom management when used correctly.
9
Effective relief
1 people found this helpful
Whenever I or a family member feels a sore throat approaching a common cold, we take a Now C-500. Within hours, the pain subsides. Now, my entire family also purchases this product.
9
Strengthens immunity
8 people found this helpful
This vitamin is essential now, particularly for combating viruses. The Now company offers a fantastic product at a good price. My family takes it regularly, and during a common cold, I increase my intake without concern, although I've noticed a tendency for heartburn over time. I began taking two tablets daily when I caught the flu, and I felt better in under a week.
9
Viral protection
2 people found this helpful
This Vitamin C is effective for viral infections. At the first signs of illness, I take two pills, while my son takes one. Most times, this stops the common cold before it starts. They should be taken with water, not chewed, as they are sour. I’m pleased with the quality and quantity per jar.
9
Boosts immunity
1 people found this helpful
Good Vitamin C. This is not my first purchase. It's effective for people with normal and low acidity. Vitamin C boosts immunity, accelerates wound healing, and aids the pancreas among other benefits. The addition of rose hips enhances immunity and combats infections. I've hardly had a common cold in two years.
9
Prevents illness
5 people found this helpful
We all take these tablets during the cold and flu season. We switched from synthetic vitamins to these natural ones from NOW Foods and it’s been rewarding. We take one tablet for prevention daily and can increase to four if anyone feels unwell. It helps us avoid the common cold!
9
Effective against viruses
7 people found this helpful
I recommend this product. I've ordered Vitamin C from this company for years and I'm very happy. It's especially beneficial for adults and children during virus season. If I feel unwell, I take 4 tablets a day along with other vitamins. It’s my go-to for common colds!
We investigated how vitamin C affects the common cold, focusing on its potential for prevention and treatment. Research indicates that while vitamin C does not prevent colds in the general population when taken at doses over 1 g/day, it has been beneficial for individuals engaging in heavy physical activity, effectively halving their incidence of colds.
Looking into regular supplementation, we found that taking 1 g or more daily can reduce the severity of colds by about 15%. However, when it comes to starting vitamin C after cold symptoms begin, results are less consistent, though higher doses of 6-8 g/day did significantly shorten the duration of colds compared to lower doses.
Interestingly, historical studies showed that vitamin C might prevent pneumonia in specific populations, such as schoolboys or soldiers, but this doesn’t translate to the general public. While some trials indicated potential benefits for pneumonia patients, the evidence is not conclusive.
Overall, we see that given the evidence supporting reduced severity and duration of colds, along with its safety and affordability, it may be worth considering a higher dose of vitamin C for those looking to manage cold symptoms better.
8
Vitamin C reduces cold incidence
Vitamin C supplementation reduces the odds of developing a common cold in Republic of Korea Army recruits: randomised controlled trial.
We conducted an insightful study to explore whether vitamin C supplementation can help reduce the incidence of common colds among Republic of Korea Army recruits. Our research involved a rigorous randomised, placebo-controlled trial that included 1,444 soldiers over a 30-day period.
In this study, we divided the participants into two groups: one received a daily dose of 6,000 mg of vitamin C while the other received a placebo with no vitamin C. We investigated the soldiers' medical records to see how many of them contracted a cold during the training period.
Our findings showed encouraging results. The group that took vitamin C had a 20% lower risk of developing a common cold compared to those who took the placebo. Interestingly, this protective effect was especially pronounced among recruits in certain training camps, as well as never smokers and those who were physically ranked at level three.
Overall, we observed that vitamin C supplementation appears to be an effective strategy for reducing the incidence of common colds in military settings, which may lead to considerations for implementing vitamin C provisions during basic training for soldiers.
5
Vitamin C's varied effects on colds
Potential Role of Vitamins and Zinc on Acute Respiratory Infections Including Covid-19.
We explored the role of Vitamin C in managing common cold symptoms through a review of existing studies. The focus was to understand whether this popular vitamin could help in reducing the incidence of the common cold or its severity.
Our findings revealed that Vitamins C, D, and E did not notably lower the incidence of the common cold in the general population. However, we did discover something interesting: Vitamin C appeared to be beneficial in individuals experiencing physical or environmental stress, reducing the incidence of the cold by half in those specific circumstances.
Moreover, while Vitamin C did not prevent colds, it did play a role in shortening their duration and minimizing the severity of symptoms. On the other hand, large doses of Vitamin A showed no effects on pneumonia recovery, and Zinc had some benefits for children under five, particularly in improving clinical deterioration.
Despite the inconclusive results regarding Vitamin C and overall cold prevention, it seems that taking this vitamin during stressful periods may still offer some advantages. Overall, while the results are mixed, there's potential for Vitamin C to be a helpful component in managing colds for specific groups.
References
Hemilä H, Chalker E. Vitamin C for the common cold and pneumonia. Pol Arch Intern Med. 2025;135. 10.20452/pamw.16926
Hemilä H, Chalker E. Vitamin C reduces the severity of common colds: a meta-analysis. BMC Public Health. 2023;23:2468. 10.1186/s12889-023-17229-8
Hemilä H, Chalker E. Bias against Vitamin C in Mainstream Medicine: Examples from Trials of Vitamin C for Infections. Life (Basel). 2022;12. 10.3390/life12010062
Murni IK, Prawirohartono EP, Triasih R. Potential Role of Vitamins and Zinc on Acute Respiratory Infections Including Covid-19. Glob Pediatr Health. 2021;8:2333794X211021739. 10.1177/2333794X211021739
Ran L, Zhao W, Wang H, Zhao Y, Bu H. Vitamin C as a Supplementary Therapy in Relieving Symptoms of the Common Cold: A Meta-Analysis of 10 Randomized Controlled Trials. Biomed Res Int. 2020;2020:8573742. 10.1155/2020/8573742
Schloss J, Lauche R, Harnett J, Hannan N, Brown D, et al. Efficacy and safety of vitamin C in the management of acute respiratory infection and disease: A rapid review. Adv Integr Med. 2020;7:187. 10.1016/j.aimed.2020.07.008
Kim TK, Lim HR, Byun JS. Vitamin C supplementation reduces the odds of developing a common cold in Republic of Korea Army recruits: randomised controlled trial. BMJ Mil Health. 2022;168:117. 10.1136/bmjmilitary-2019-001384