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Overview
SCIENTIFIC SCORE
Possibly Effective
Based on 7 Researches
7.1
USERS' SCORE
Good
Based on 2 Reviews
8.6
Top Medical Research Studies
8
We explored the connection between vitamin D levels and upper respiratory tract infections (URTIs) among military recruits during their training. This observation spanned across different seasons and included over 1,600 recruits. Our aim was to understand how achieving sufficient vitamin D levels could potentially impact the frequency and severity of colds among physically active individuals.
In an additional phase of the research, we conducted a randomized controlled trial with 250 male recruits. They received either a placebo, simulated sunlight exposure, or oral vitamin D3 supplements during winter. This comparison allowed us to see if these methods effectively increased vitamin D levels to a sufficient status of 25(OH)D at 50 nmol/L or higher.
Notably, our findings showed that only 21% of recruits had adequate vitamin D during winter, yet those who did were 40% less likely to suffer from URTIs. Furthermore, both vitamin D supplementation strategies similarly helped nearly all participants achieve sufficient levels. Vitamin D supplementation notably reduced the severity of URTI symptoms by 15% and the number of days with URTIs by 36% compared to placebo.
While the supplementation strategies did not significantly alter other immune factors, such as salivary secretory immunoglobulin A, the overall reduction in respiratory infections indicates a beneficial effect of maintaining vitamin D sufficiency during military training.
In an additional phase of the research, we conducted a randomized controlled trial with 250 male recruits. They received either a placebo, simulated sunlight exposure, or oral vitamin D3 supplements during winter. This comparison allowed us to see if these methods effectively increased vitamin D levels to a sufficient status of 25(OH)D at 50 nmol/L or higher.
Notably, our findings showed that only 21% of recruits had adequate vitamin D during winter, yet those who did were 40% less likely to suffer from URTIs. Furthermore, both vitamin D supplementation strategies similarly helped nearly all participants achieve sufficient levels. Vitamin D supplementation notably reduced the severity of URTI symptoms by 15% and the number of days with URTIs by 36% compared to placebo.
While the supplementation strategies did not significantly alter other immune factors, such as salivary secretory immunoglobulin A, the overall reduction in respiratory infections indicates a beneficial effect of maintaining vitamin D sufficiency during military training.
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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.
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
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.
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
9
Effective product
5 people found this helpful
MY NEW GO-TO IN THE MORNING, FIRST THING!! A++!! I’ve been using the 'Emergen-C' brand for over a decade, especially during the cold and flu season. Though they are pricey, I discovered a similar brand on Amazon at a much better price. I tried these and I’m hooked. THEY ARE DELICIOUS! My favourite is grapefruit-tangerine; all flavours are brilliant. They dissolve quickly, even in colder water. I’ve even blended them into smoothies for an extra boost...FANTASTIC PRODUCT!! I’m already sharing them with friends...don’t overspend on the other brand. THESE ARE AWESOME!! (AND YES, THEY WORK! Instant energy boost, the healthy way!!)
Read More
9
Cold free
5 people found this helpful
Good stuff! My husband and I have taken one of these every morning for about six months now. We just got through the cold and flu season without any illness! I have also given up coffee in the morning, mainly due to the amount of cream I used. This gives me the pick-me-up I need, and I really like the flavour.
Read More
Medical Researches
SCIENTIFIC SCORE
Possibly Effective
Based on 7 Researches
7.1
- All Researches
9
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.
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
8
We explored the connection between vitamin D levels and upper respiratory tract infections (URTIs) among military recruits during their training. This observation spanned across different seasons and included over 1,600 recruits. Our aim was to understand how achieving sufficient vitamin D levels could potentially impact the frequency and severity of colds among physically active individuals.
In an additional phase of the research, we conducted a randomized controlled trial with 250 male recruits. They received either a placebo, simulated sunlight exposure, or oral vitamin D3 supplements during winter. This comparison allowed us to see if these methods effectively increased vitamin D levels to a sufficient status of 25(OH)D at 50 nmol/L or higher.
Notably, our findings showed that only 21% of recruits had adequate vitamin D during winter, yet those who did were 40% less likely to suffer from URTIs. Furthermore, both vitamin D supplementation strategies similarly helped nearly all participants achieve sufficient levels. Vitamin D supplementation notably reduced the severity of URTI symptoms by 15% and the number of days with URTIs by 36% compared to placebo.
While the supplementation strategies did not significantly alter other immune factors, such as salivary secretory immunoglobulin A, the overall reduction in respiratory infections indicates a beneficial effect of maintaining vitamin D sufficiency during military training.
In an additional phase of the research, we conducted a randomized controlled trial with 250 male recruits. They received either a placebo, simulated sunlight exposure, or oral vitamin D3 supplements during winter. This comparison allowed us to see if these methods effectively increased vitamin D levels to a sufficient status of 25(OH)D at 50 nmol/L or higher.
Notably, our findings showed that only 21% of recruits had adequate vitamin D during winter, yet those who did were 40% less likely to suffer from URTIs. Furthermore, both vitamin D supplementation strategies similarly helped nearly all participants achieve sufficient levels. Vitamin D supplementation notably reduced the severity of URTI symptoms by 15% and the number of days with URTIs by 36% compared to placebo.
While the supplementation strategies did not significantly alter other immune factors, such as salivary secretory immunoglobulin A, the overall reduction in respiratory infections indicates a beneficial effect of maintaining vitamin D sufficiency during military training.
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.
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
7
We evaluated the impact of high-dose vitamin D supplementation, specifically doses exceeding the standard 400 IU, on preventing colds and other infections in children under five years of age. Our analysis included seven studies, involving a total of 5,748 children, which looked into how effective vitamin D might be in reducing the incidence of upper respiratory tract infections.
Interestingly, while our findings showed no significant benefit of high-dose vitamin D on the prevention of upper respiratory tract infections as a whole, we did observe a noteworthy reduction in specific illness occurrences. We noted a 57% reduction in colds, a 56% reduction in coughs, and a 59% decrease in fever rates with daily doses exceeding 1,000 IU.
However, we must approach these findings with caution, as the evidence supporting the reduction in cough and fever was of lower certainty. No significant effects were observed regarding other conditions such as bronchitis or otitis media. Overall, while high-dose vitamin D may help with colds specifically, further research is needed to solidify these conclusions.
Interestingly, while our findings showed no significant benefit of high-dose vitamin D on the prevention of upper respiratory tract infections as a whole, we did observe a noteworthy reduction in specific illness occurrences. We noted a 57% reduction in colds, a 56% reduction in coughs, and a 59% decrease in fever rates with daily doses exceeding 1,000 IU.
However, we must approach these findings with caution, as the evidence supporting the reduction in cough and fever was of lower certainty. No significant effects were observed regarding other conditions such as bronchitis or otitis media. Overall, while high-dose vitamin D may help with colds specifically, further research is needed to solidify these conclusions.
Read More
7
We explored the impact of vitamin D and B12 deficiencies in children experiencing primary Raynaud phenomenon (RP), which causes temporary blood flow changes often triggered by cold or stress. Our study aimed to identify how common these vitamin deficiencies are in pediatric patients and whether they influenced the severity of Raynaud symptoms.
Out of 40 young participants, a significant portion—41.5% for vitamin B12 and 39% for vitamin D—showed low serum levels of these vitamins. After providing supplementation, we observed improved symptoms in many cases, particularly through warming techniques. However, it's important to note that while vasodilator treatment needs were generally unchanged regardless of vitamin B12 levels, those who had vitamin D deficiencies and subsequently received vitamin D treatment required significantly less vasodilator therapy.
Overall, while some positive effects of vitamin D were noted, further research is necessary to conclusively determine its role in managing primary RP symptoms and its effectiveness in combating cold-induced episodes.
Out of 40 young participants, a significant portion—41.5% for vitamin B12 and 39% for vitamin D—showed low serum levels of these vitamins. After providing supplementation, we observed improved symptoms in many cases, particularly through warming techniques. However, it's important to note that while vasodilator treatment needs were generally unchanged regardless of vitamin B12 levels, those who had vitamin D deficiencies and subsequently received vitamin D treatment required significantly less vasodilator therapy.
Overall, while some positive effects of vitamin D were noted, further research is necessary to conclusively determine its role in managing primary RP symptoms and its effectiveness in combating cold-induced episodes.
Read More
User Reviews
USERS' SCORE
Good
Based on 2 Reviews
8.6
- All Reviews
- Positive Reviews
- Negative Reviews
9
Effective product
5 people found this helpful
MY NEW GO-TO IN THE MORNING, FIRST THING!! A++!! I’ve been using the 'Emergen-C' brand for over a decade, especially during the cold and flu season. Though they are pricey, I discovered a similar brand on Amazon at a much better price. I tried these and I’m hooked. THEY ARE DELICIOUS! My favourite is grapefruit-tangerine; all flavours are brilliant. They dissolve quickly, even in colder water. I’ve even blended them into smoothies for an extra boost...FANTASTIC PRODUCT!! I’m already sharing them with friends...don’t overspend on the other brand. THESE ARE AWESOME!! (AND YES, THEY WORK! Instant energy boost, the healthy way!!)
Read More
9
Cold free
5 people found this helpful
Good stuff! My husband and I have taken one of these every morning for about six months now. We just got through the cold and flu season without any illness! I have also given up coffee in the morning, mainly due to the amount of cream I used. This gives me the pick-me-up I need, and I really like the flavour.
Read More
Frequently Asked Questions
No FAQs are available for this product and symptom.
References
- Hemilä H, Chalker E. Vitamin C for the common cold and pneumonia. Pol Arch Intern Med. 2025;135. 10.20452/pamw.16926
- 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
- Marusca LM, Reddy G, Blaj M, Prathipati R, Rosca O, et al. The Effects of Vitamin D Supplementation on Respiratory Infections in Children under 6 Years Old: A Systematic Review. Diseases. 2023;11. 10.3390/diseases11030104
- Carboo JA, Dolman-Macleod RC, Malan L, Lombard MJ. High-dose oral vitamin D supplementation for prevention of infections in children aged 0 to 59 months: a systematic review and meta-analysis. Nutr Rev. 2024;82:579. 10.1093/nutrit/nuad082
- Kisla Ekinci RM, Taskin Karacay IE, Celik U. Serum vitamin B12 and D levels in children with Primary Raynaud Phenomenon: a retrospective cohort study. Eur J Clin Nutr. 2022;76:1615. 10.1038/s41430-022-01151-0
- Harrison SE, Oliver SJ, Kashi DS, Carswell AT, Edwards JP, et al. Influence of Vitamin D Supplementation by Simulated Sunlight or Oral D3 on Respiratory Infection during Military Training. Med Sci Sports Exerc. 2021;53:1505. 10.1249/MSS.0000000000002604
- Shimizu Y, Ito Y, Uotsu N, Yui K. Intake of 25-Hydroxyvitamin D May Reduce the Severity of Upper Respiratory Tract Infection: Post hoc Analysis of a Randomized, Double-Blind, Placebo-Controlled, Parallel Group Comparison Study. Nutrients. 2020;12. 10.3390/nu12123769
