Overview
SCIENTIFIC SCORE
Questionable
Based on 15 Researches
6.7
USERS' SCORE
Good
Based on 7 Reviews
8.5
Supplement Facts
Serving Size: 1 Vegetable Capsule
Amount Per Serving
%DV
Vitamin D3 (as cholecalciferol)
125 mcg (5000 IU)
625%
Top Medical Research Studies
8
We explored the potential benefits of vitamin D supplementation for reducing the risk of influenza infections. Through a comprehensive analysis of multiple Randomized Controlled Trials (RCTs), we aimed to clarify whether taking vitamin D can help prevent the flu.
Our investigation identified 10 relevant trials that included a total of 4,859 participants. These studies varied in their dosages and duration of vitamin D use, allowing us to assess overall effectiveness across different populations.
The findings were encouraging: our analysis demonstrated that vitamin D supplementation appears to significantly reduce the risk of getting influenza, suggesting that those who increase their vitamin D intake might be better protected during flu season.
Importantly, we did not find significant differences between the studies that could affect our result, and there was no hint of publication bias. Consequently, we can confidently suggest that including vitamin D in our health strategies could enhance our defenses against the flu.
Our investigation identified 10 relevant trials that included a total of 4,859 participants. These studies varied in their dosages and duration of vitamin D use, allowing us to assess overall effectiveness across different populations.
The findings were encouraging: our analysis demonstrated that vitamin D supplementation appears to significantly reduce the risk of getting influenza, suggesting that those who increase their vitamin D intake might be better protected during flu season.
Importantly, we did not find significant differences between the studies that could affect our result, and there was no hint of publication bias. Consequently, we can confidently suggest that including vitamin D in our health strategies could enhance our defenses against the flu.
Read More
8
We carried out a study to investigate whether vitamin D3 supplements could help prevent seasonal influenza A in schoolchildren. Our approach involved a randomized, double-blind, placebo-controlled trial conducted from December 2008 to March 2009.
This ensured that neither the participants nor the researchers knew who was receiving the vitamin D3 or the placebo, making our findings more reliable. During the trial, we provided 1200 IU of vitamin D3 daily to one group while the other received a placebo.
The results were promising; we found that only 10.8% of the children taking vitamin D3 contracted influenza A, compared to 18.6% in the placebo group. This reduced incidence led us to a relative risk of 0.58, suggesting that vitamin D3 supplementation may lower the chances of getting the flu.
Interestingly, we noticed the most significant benefits among children who hadn’t been taking any other vitamin D supplements and those who began nursery school after age three. Additionally, in children with a past asthma diagnosis, vitamin D3 seemed to dramatically reduce asthma attacks.
Overall, our findings indicate that taking vitamin D3 in the winter could be beneficial for schoolchildren, especially for certain groups. We believe this study adds valuable insights into preventive health measures against influenza A.
This ensured that neither the participants nor the researchers knew who was receiving the vitamin D3 or the placebo, making our findings more reliable. During the trial, we provided 1200 IU of vitamin D3 daily to one group while the other received a placebo.
The results were promising; we found that only 10.8% of the children taking vitamin D3 contracted influenza A, compared to 18.6% in the placebo group. This reduced incidence led us to a relative risk of 0.58, suggesting that vitamin D3 supplementation may lower the chances of getting the flu.
Interestingly, we noticed the most significant benefits among children who hadn’t been taking any other vitamin D supplements and those who began nursery school after age three. Additionally, in children with a past asthma diagnosis, vitamin D3 seemed to dramatically reduce asthma attacks.
Overall, our findings indicate that taking vitamin D3 in the winter could be beneficial for schoolchildren, especially for certain groups. We believe this study adds valuable insights into preventive health measures against influenza A.
Read More
8
We conducted a practical study to investigate how daily vitamin D3 supplementation at 5000 IU might help reduce flu-like illnesses in healthcare workers. This was especially important during the COVID-19 pandemic, where preventing viral infections is crucial for those on the front lines.
Our study involved 255 healthcare workers who received the vitamin D3 supplement for at least two months and compared them to a control group of 2827 workers who did not receive the supplement. We asked participants to monitor themselves for any flu-like symptoms and report for COVID-19 testing accordingly.
The results were promising; those supplementing with vitamin D experienced a significant reduction in the incidence of flu-like illnesses. The numbers showed a noteworthy drop in non-COVID-19 flu-like illness rates among those taking the supplement. However, when it came to COVID-19 related flu-like illnesses, the difference was not statistically significant.
Overall, our exploration of vitamin D3's effects suggests that it may be a beneficial addition to the health routines of healthcare workers to stave off flu-like illnesses, although its influence on COVID-19 specifically requires further investigation.
Our study involved 255 healthcare workers who received the vitamin D3 supplement for at least two months and compared them to a control group of 2827 workers who did not receive the supplement. We asked participants to monitor themselves for any flu-like symptoms and report for COVID-19 testing accordingly.
The results were promising; those supplementing with vitamin D experienced a significant reduction in the incidence of flu-like illnesses. The numbers showed a noteworthy drop in non-COVID-19 flu-like illness rates among those taking the supplement. However, when it came to COVID-19 related flu-like illnesses, the difference was not statistically significant.
Overall, our exploration of vitamin D3's effects suggests that it may be a beneficial addition to the health routines of healthcare workers to stave off flu-like illnesses, although its influence on COVID-19 specifically requires further investigation.
Read More
Most Useful Reviews
9
Prevented flu
I took this alongside Omega 3, 6, 9 and Calcium for two months. During the local influenza outbreak, my family fell ill, yet I remained well. Normally, I easily catch viruses, especially in summer. After finishing the course, I noticed my skin and hair improved, with significantly less hair loss, likely due to the cumulative effect. Previously, I had a vitamin D3 deficiency, but I haven't checked my levels since.
Read More
9
Improved flu resistance
Great D3! My nerves, mood, cheerfulness, nails, and hair have all improved. My resistance to colds and flu is excellent. The quality is perfect, as expected from this brand. The timing and composition are superb. I highly recommend it, and the smell is neutral. Definitely beneficial.
Read More
9
No flu experienced
I have a fantastic review of this vitamin. My whole family takes it, including my elderly parents aged 75 and 80. With normal vitamin D levels, we haven't caught any colds or flu—it's been tested in practice. We are very satisfied.
Read More
Medical Researches
SCIENTIFIC SCORE
Questionable
Based on 15 Researches
6.7
- All Researches
9
We recently examined how vitamin D impacts our body's response to influenza H1N1, an important viral infection. Utilizing 142 clinical cases from the Department of Otolaryngology at Sun Yat-sen University, we dug into the effects of vitamin D deficiency on chronic rhinosinusitis (CRS), a condition that frequently involves damage to the airway's lining. By studying airway organoids treated with vitamin D, we were able to simulate how this treatment might bolster our defenses against flu viruses and bacteria like Staphylococcus aureus.
Our observations showed that many patients with CRS suffered from vitamin D deficiency. Notably, those who received vitamin D treatment exhibited faster cell growth in the nasal epithelium. When exposed to the H1N1 virus, these treated organoids demonstrated a remarkable ability to fend off the infection better than those without vitamin D. This protection stemmed from enhancements in host defenses, including improved production of antimicrobial proteins, reduced inflammation, and better epithelial integrity—crucial factors in fighting off infections.
We also uncovered some fascinating insights about the biological mechanisms at work. Vitamin D seemed to actively influence how epithelial cells develop and repair themselves while managing immune responses against infections. These findings underscore the significance of addressing vitamin D deficiency, especially for those vulnerable to respiratory illnesses.
Our observations showed that many patients with CRS suffered from vitamin D deficiency. Notably, those who received vitamin D treatment exhibited faster cell growth in the nasal epithelium. When exposed to the H1N1 virus, these treated organoids demonstrated a remarkable ability to fend off the infection better than those without vitamin D. This protection stemmed from enhancements in host defenses, including improved production of antimicrobial proteins, reduced inflammation, and better epithelial integrity—crucial factors in fighting off infections.
We also uncovered some fascinating insights about the biological mechanisms at work. Vitamin D seemed to actively influence how epithelial cells develop and repair themselves while managing immune responses against infections. These findings underscore the significance of addressing vitamin D deficiency, especially for those vulnerable to respiratory illnesses.
Read More
9
We explored the potential of Oxarol, a medication usually prescribed for psoriasis, as a new adjuvant for influenza vaccines. In our research, we found that applying Oxarol ointment on the skin significantly enhanced the immune response of mice when they were vaccinated against the flu. This treatment helped boost humoral responses—essentially the production of antibodies—and improved germinal center reactions, which are critical for effective immunity.
Our findings highlighted that the vitamin D3 receptor in skin cells played a vital role in this process. By stimulating the production of a molecule called thymic stromal lymphopoietin (TSLP), Oxarol effectively facilitated better immune responses against the virus. Experiments showed that giving mice TSLP directly or blocking it produced noticeable changes in their immune responses, indicating its importance.
Importantly, we identified specific immune cells responsible for the effective response, confirming that targeted treatments like Oxarol could pave the way for safer and more efficient vaccine strategies in the future. This study suggests that vitamin D3’s role in skin treatments can be harnessed to improve flu vaccines.
Our findings highlighted that the vitamin D3 receptor in skin cells played a vital role in this process. By stimulating the production of a molecule called thymic stromal lymphopoietin (TSLP), Oxarol effectively facilitated better immune responses against the virus. Experiments showed that giving mice TSLP directly or blocking it produced noticeable changes in their immune responses, indicating its importance.
Importantly, we identified specific immune cells responsible for the effective response, confirming that targeted treatments like Oxarol could pave the way for safer and more efficient vaccine strategies in the future. This study suggests that vitamin D3’s role in skin treatments can be harnessed to improve flu vaccines.
Read More
8
We explored how vitamin D supplementation might help reduce the risk of respiratory infections, particularly the flu, in care homes. Our systematic review of several randomized controlled trials focused on interventions to reduce the transmission of acute respiratory infections, looking beyond just vaccines.
Our findings highlighted that high-dose vitamin D supplementation led to a significant decrease in the incidence of acute respiratory infections, reducing the likelihood of getting sick. Specifically, one trial indicated a 40% reduction in these infections among participants receiving vitamin D compared to those who did not.
However, not all studies we reviewed showed compelling results for related supplements like vitamins, minerals, probiotics, and herbal aids, which did not significantly impact infection rates. This means that while vitamin D supplementation shows promise, more research is needed to fully understand its effects and confirm its benefits in combating flu and other respiratory illnesses.
Our findings highlighted that high-dose vitamin D supplementation led to a significant decrease in the incidence of acute respiratory infections, reducing the likelihood of getting sick. Specifically, one trial indicated a 40% reduction in these infections among participants receiving vitamin D compared to those who did not.
However, not all studies we reviewed showed compelling results for related supplements like vitamins, minerals, probiotics, and herbal aids, which did not significantly impact infection rates. This means that while vitamin D supplementation shows promise, more research is needed to fully understand its effects and confirm its benefits in combating flu and other respiratory illnesses.
Read More
8
We conducted a practical study to investigate how daily vitamin D3 supplementation at 5000 IU might help reduce flu-like illnesses in healthcare workers. This was especially important during the COVID-19 pandemic, where preventing viral infections is crucial for those on the front lines.
Our study involved 255 healthcare workers who received the vitamin D3 supplement for at least two months and compared them to a control group of 2827 workers who did not receive the supplement. We asked participants to monitor themselves for any flu-like symptoms and report for COVID-19 testing accordingly.
The results were promising; those supplementing with vitamin D experienced a significant reduction in the incidence of flu-like illnesses. The numbers showed a noteworthy drop in non-COVID-19 flu-like illness rates among those taking the supplement. However, when it came to COVID-19 related flu-like illnesses, the difference was not statistically significant.
Overall, our exploration of vitamin D3's effects suggests that it may be a beneficial addition to the health routines of healthcare workers to stave off flu-like illnesses, although its influence on COVID-19 specifically requires further investigation.
Our study involved 255 healthcare workers who received the vitamin D3 supplement for at least two months and compared them to a control group of 2827 workers who did not receive the supplement. We asked participants to monitor themselves for any flu-like symptoms and report for COVID-19 testing accordingly.
The results were promising; those supplementing with vitamin D experienced a significant reduction in the incidence of flu-like illnesses. The numbers showed a noteworthy drop in non-COVID-19 flu-like illness rates among those taking the supplement. However, when it came to COVID-19 related flu-like illnesses, the difference was not statistically significant.
Overall, our exploration of vitamin D3's effects suggests that it may be a beneficial addition to the health routines of healthcare workers to stave off flu-like illnesses, although its influence on COVID-19 specifically requires further investigation.
Read More
8
We explored the potential benefits of vitamin D supplementation for reducing the risk of influenza infections. Through a comprehensive analysis of multiple Randomized Controlled Trials (RCTs), we aimed to clarify whether taking vitamin D can help prevent the flu.
Our investigation identified 10 relevant trials that included a total of 4,859 participants. These studies varied in their dosages and duration of vitamin D use, allowing us to assess overall effectiveness across different populations.
The findings were encouraging: our analysis demonstrated that vitamin D supplementation appears to significantly reduce the risk of getting influenza, suggesting that those who increase their vitamin D intake might be better protected during flu season.
Importantly, we did not find significant differences between the studies that could affect our result, and there was no hint of publication bias. Consequently, we can confidently suggest that including vitamin D in our health strategies could enhance our defenses against the flu.
Our investigation identified 10 relevant trials that included a total of 4,859 participants. These studies varied in their dosages and duration of vitamin D use, allowing us to assess overall effectiveness across different populations.
The findings were encouraging: our analysis demonstrated that vitamin D supplementation appears to significantly reduce the risk of getting influenza, suggesting that those who increase their vitamin D intake might be better protected during flu season.
Importantly, we did not find significant differences between the studies that could affect our result, and there was no hint of publication bias. Consequently, we can confidently suggest that including vitamin D in our health strategies could enhance our defenses against the flu.
Read More
User Reviews
USERS' SCORE
Good
Based on 7 Reviews
8.5
- All Reviews
- Positive Reviews
- Negative Reviews
9
Prevented flu
I took this alongside Omega 3, 6, 9 and Calcium for two months. During the local influenza outbreak, my family fell ill, yet I remained well. Normally, I easily catch viruses, especially in summer. After finishing the course, I noticed my skin and hair improved, with significantly less hair loss, likely due to the cumulative effect. Previously, I had a vitamin D3 deficiency, but I haven't checked my levels since.
Read More
9
Improved flu resistance
Great D3! My nerves, mood, cheerfulness, nails, and hair have all improved. My resistance to colds and flu is excellent. The quality is perfect, as expected from this brand. The timing and composition are superb. I highly recommend it, and the smell is neutral. Definitely beneficial.
Read More
9
No flu experienced
I have a fantastic review of this vitamin. My whole family takes it, including my elderly parents aged 75 and 80. With normal vitamin D levels, we haven't caught any colds or flu—it's been tested in practice. We are very satisfied.
Read More
9
Avoided flu
Solgar's Natural Vitamin D3, 5000 IU, 240 Veggie Caps is an excellent product. I managed to avoid the flu entirely last year.
Read More
7.5
Fighting influenza
Excellent quality, which is vital for immunity and combating influenza and viruses.
Read More
Frequently Asked Questions
9
Prevented flu
I took this alongside Omega 3, 6, 9 and Calcium for two months. During the local influenza outbreak, my family fell ill, yet I remained well. Normally, I easily catch viruses, especially in summer. After finishing the course, I noticed my skin and hair improved, with significantly less hair loss, likely due to the cumulative effect. Previously, I had a vitamin D3 deficiency, but I haven't checked my levels since.
9
No flu experienced
I have a fantastic review of this vitamin. My whole family takes it, including my elderly parents aged 75 and 80. With normal vitamin D levels, we haven't caught any colds or flu—it's been tested in practice. We are very satisfied.
9
Avoided flu
Solgar's Natural Vitamin D3, 5000 IU, 240 Veggie Caps is an excellent product. I managed to avoid the flu entirely last year.
9
Improved flu resistance
Great D3! My nerves, mood, cheerfulness, nails, and hair have all improved. My resistance to colds and flu is excellent. The quality is perfect, as expected from this brand. The timing and composition are superb. I highly recommend it, and the smell is neutral. Definitely beneficial.
7.5
Supports immunity
Sun in every capsule. Great vitamins at the right dosage, supporting immunity and health during colds and flu in autumn and spring when sunlight and vitamins are scarce. They can be combined with other vitamins from this manufacturer, like omega and magnesium, to keep the body in shape.
8
We explored how vitamin D supplementation might help reduce the risk of respiratory infections, particularly the flu, in care homes. Our systematic review of several randomized controlled trials focused on interventions to reduce the transmission of acute respiratory infections, looking beyond just vaccines.
Our findings highlighted that high-dose vitamin D supplementation led to a significant decrease in the incidence of acute respiratory infections, reducing the likelihood of getting sick. Specifically, one trial indicated a 40% reduction in these infections among participants receiving vitamin D compared to those who did not.
However, not all studies we reviewed showed compelling results for related supplements like vitamins, minerals, probiotics, and herbal aids, which did not significantly impact infection rates. This means that while vitamin D supplementation shows promise, more research is needed to fully understand its effects and confirm its benefits in combating flu and other respiratory illnesses.
Our findings highlighted that high-dose vitamin D supplementation led to a significant decrease in the incidence of acute respiratory infections, reducing the likelihood of getting sick. Specifically, one trial indicated a 40% reduction in these infections among participants receiving vitamin D compared to those who did not.
However, not all studies we reviewed showed compelling results for related supplements like vitamins, minerals, probiotics, and herbal aids, which did not significantly impact infection rates. This means that while vitamin D supplementation shows promise, more research is needed to fully understand its effects and confirm its benefits in combating flu and other respiratory illnesses.
9
We recently examined how vitamin D impacts our body's response to influenza H1N1, an important viral infection. Utilizing 142 clinical cases from the Department of Otolaryngology at Sun Yat-sen University, we dug into the effects of vitamin D deficiency on chronic rhinosinusitis (CRS), a condition that frequently involves damage to the airway's lining. By studying airway organoids treated with vitamin D, we were able to simulate how this treatment might bolster our defenses against flu viruses and bacteria like Staphylococcus aureus.
Our observations showed that many patients with CRS suffered from vitamin D deficiency. Notably, those who received vitamin D treatment exhibited faster cell growth in the nasal epithelium. When exposed to the H1N1 virus, these treated organoids demonstrated a remarkable ability to fend off the infection better than those without vitamin D. This protection stemmed from enhancements in host defenses, including improved production of antimicrobial proteins, reduced inflammation, and better epithelial integrity—crucial factors in fighting off infections.
We also uncovered some fascinating insights about the biological mechanisms at work. Vitamin D seemed to actively influence how epithelial cells develop and repair themselves while managing immune responses against infections. These findings underscore the significance of addressing vitamin D deficiency, especially for those vulnerable to respiratory illnesses.
Our observations showed that many patients with CRS suffered from vitamin D deficiency. Notably, those who received vitamin D treatment exhibited faster cell growth in the nasal epithelium. When exposed to the H1N1 virus, these treated organoids demonstrated a remarkable ability to fend off the infection better than those without vitamin D. This protection stemmed from enhancements in host defenses, including improved production of antimicrobial proteins, reduced inflammation, and better epithelial integrity—crucial factors in fighting off infections.
We also uncovered some fascinating insights about the biological mechanisms at work. Vitamin D seemed to actively influence how epithelial cells develop and repair themselves while managing immune responses against infections. These findings underscore the significance of addressing vitamin D deficiency, especially for those vulnerable to respiratory illnesses.
8
We conducted a practical study to investigate how daily vitamin D3 supplementation at 5000 IU might help reduce flu-like illnesses in healthcare workers. This was especially important during the COVID-19 pandemic, where preventing viral infections is crucial for those on the front lines.
Our study involved 255 healthcare workers who received the vitamin D3 supplement for at least two months and compared them to a control group of 2827 workers who did not receive the supplement. We asked participants to monitor themselves for any flu-like symptoms and report for COVID-19 testing accordingly.
The results were promising; those supplementing with vitamin D experienced a significant reduction in the incidence of flu-like illnesses. The numbers showed a noteworthy drop in non-COVID-19 flu-like illness rates among those taking the supplement. However, when it came to COVID-19 related flu-like illnesses, the difference was not statistically significant.
Overall, our exploration of vitamin D3's effects suggests that it may be a beneficial addition to the health routines of healthcare workers to stave off flu-like illnesses, although its influence on COVID-19 specifically requires further investigation.
Our study involved 255 healthcare workers who received the vitamin D3 supplement for at least two months and compared them to a control group of 2827 workers who did not receive the supplement. We asked participants to monitor themselves for any flu-like symptoms and report for COVID-19 testing accordingly.
The results were promising; those supplementing with vitamin D experienced a significant reduction in the incidence of flu-like illnesses. The numbers showed a noteworthy drop in non-COVID-19 flu-like illness rates among those taking the supplement. However, when it came to COVID-19 related flu-like illnesses, the difference was not statistically significant.
Overall, our exploration of vitamin D3's effects suggests that it may be a beneficial addition to the health routines of healthcare workers to stave off flu-like illnesses, although its influence on COVID-19 specifically requires further investigation.
3
We set out to explore whether a three-month regimen of vitamin D supplementation could lower the risk of influenza infection in elderly nursing home residents who had already received the seasonal flu vaccine. In our study, 97 participants were enrolled, with more than 73% being women. They were divided into two groups: one received vitamin D supplements, while the other did not.
Even though we found that fewer participants in the vitamin D group tested positive for the flu compared to the control group (five versus twelve), the difference was not statistically significant. Most importantly, despite taking the recommended 800 IU of vitamin D each day, residents did not reach sufficient vitamin D levels, and the supplementation did not appear to have any beneficial effect on preventing influenza infections among those already vaccinated.
This highlights a critical aspect: despite being one of the recommended strategies for health improvement, standard vitamin D supplementation may not be effective in significantly reducing the risk of flu in this vulnerable population.
Even though we found that fewer participants in the vitamin D group tested positive for the flu compared to the control group (five versus twelve), the difference was not statistically significant. Most importantly, despite taking the recommended 800 IU of vitamin D each day, residents did not reach sufficient vitamin D levels, and the supplementation did not appear to have any beneficial effect on preventing influenza infections among those already vaccinated.
This highlights a critical aspect: despite being one of the recommended strategies for health improvement, standard vitamin D supplementation may not be effective in significantly reducing the risk of flu in this vulnerable population.
5
We conducted a randomized, double-blind, controlled trial to explore whether vitamin D supplementation could lower the risk of flu among young children. The study involved 248 participants aged two to five years from daycare centers in Taiwan, who were divided into two groups: one received 2000 IU of vitamin D daily, while the other group received a placebo for one month.
The results were intriguing. We found an 84% relative risk reduction for flu infection in the vitamin D group compared to the placebo group. However, this finding did not achieve statistical significance, which means we can't be certain of its importance. The data suggested that the placebo group might have a higher chance of getting the flu, but again, the results were not definitive.
Additionally, no significant differences were observed in terms of enterovirus infections between the two groups, and the same trend was seen among household members of the children. Everyone who received the vitamin D treatment managed to raise their vitamin D levels above 30 ng/ml, indicating that the supplementation was effective in boosting their vitamin D status.
Overall, while vitamin D supplementation might offer some protective effect against flu in preschoolers, the evidence does not strongly support this. We recommend further research to fully understand the impact.
The results were intriguing. We found an 84% relative risk reduction for flu infection in the vitamin D group compared to the placebo group. However, this finding did not achieve statistical significance, which means we can't be certain of its importance. The data suggested that the placebo group might have a higher chance of getting the flu, but again, the results were not definitive.
Additionally, no significant differences were observed in terms of enterovirus infections between the two groups, and the same trend was seen among household members of the children. Everyone who received the vitamin D treatment managed to raise their vitamin D levels above 30 ng/ml, indicating that the supplementation was effective in boosting their vitamin D status.
Overall, while vitamin D supplementation might offer some protective effect against flu in preschoolers, the evidence does not strongly support this. We recommend further research to fully understand the impact.
8
We explored the potential benefits of vitamin D supplementation for reducing the risk of influenza infections. Through a comprehensive analysis of multiple Randomized Controlled Trials (RCTs), we aimed to clarify whether taking vitamin D can help prevent the flu.
Our investigation identified 10 relevant trials that included a total of 4,859 participants. These studies varied in their dosages and duration of vitamin D use, allowing us to assess overall effectiveness across different populations.
The findings were encouraging: our analysis demonstrated that vitamin D supplementation appears to significantly reduce the risk of getting influenza, suggesting that those who increase their vitamin D intake might be better protected during flu season.
Importantly, we did not find significant differences between the studies that could affect our result, and there was no hint of publication bias. Consequently, we can confidently suggest that including vitamin D in our health strategies could enhance our defenses against the flu.
Our investigation identified 10 relevant trials that included a total of 4,859 participants. These studies varied in their dosages and duration of vitamin D use, allowing us to assess overall effectiveness across different populations.
The findings were encouraging: our analysis demonstrated that vitamin D supplementation appears to significantly reduce the risk of getting influenza, suggesting that those who increase their vitamin D intake might be better protected during flu season.
Importantly, we did not find significant differences between the studies that could affect our result, and there was no hint of publication bias. Consequently, we can confidently suggest that including vitamin D in our health strategies could enhance our defenses against the flu.
References
- Willcox ML, Lavu D, Yousaf U, Dalton S, Roberts N, et al. The effectiveness of interventions to reduce the transmission of acute respiratory infections in care homes: a systematic review. J Public Health (Oxf). 2024;46:551. doi:10.1093/pubmed/fdae178
- Liao S, Huang Y, Zhang J, Xiong Q, Chi M, et al. Vitamin D promotes epithelial tissue repair and host defense responses against influenza H1N1 virus and Staphylococcus aureus infections. Respir Res. 2023;24:175. doi:10.1186/s12931-023-02477-4
- van Helmond N, Brobyn TL, LaRiccia PJ, Cafaro T, Hunter K, et al. Vitamin D3 Supplementation at 5000 IU Daily for the Prevention of Influenza-like Illness in Healthcare Workers: A Pragmatic Randomized Clinical Trial. Nutrients. 2022;15. doi:10.3390/nu15010180
- Arora J, Patel DR, Nicol MJ, Field CJ, Restori KH, et al. Vitamin D and the Ability to Produce 1,25(OH)D Are Critical for Protection from Viral Infection of the Lungs. Nutrients. 2022;14. doi:10.3390/nu14153061
- Huang YN, Chi H, Chiu NC, Huang CY, Li ST, et al. A randomized trial of vitamin D supplementation to prevent seasonal influenza and enterovirus infection in children. J Microbiol Immunol Infect. 2022;55:803. doi:10.1016/j.jmii.2022.01.003
- Zhu Z, Zhu X, Gu L, Zhan Y, Chen L, et al. Association Between Vitamin D and Influenza: Meta-Analysis and Systematic Review of Randomized Controlled Trials. Front Nutr. 2021;8:799709. doi:10.3389/fnut.2021.799709
- Godan Hauptman A, Lukić-Grlić A, Vraneš J, Milošević M, Gagro A. The effect of standard-dose wintertime vitamin D supplementation on influenza infection in immunized nursing home elderly residents. Croat Med J. 2021;62:495.
- Abioye AI, Bromage S, Fawzi W. Effect of micronutrient supplements on influenza and other respiratory tract infections among adults: a systematic review and meta-analysis. BMJ Glob Health. 2021;6. doi:10.1136/bmjgh-2020-003176
- Slusky DJG, Zeckhauser RJ. Sunlight and Protection Against Influenza. Econ Hum Biol. 2021;40:100942. doi:10.1016/j.ehb.2020.100942
- Godbole NM, Sinha RA, Tiwari S, Pawar SD, Dhole TN. Analysis of influenza virus-induced perturbation in autophagic flux and its modulation during Vitamin D3 mediated anti-apoptotic signaling. Virus Res. 2020;282:197936. doi:10.1016/j.virusres.2020.197936
- Sato R, Makino-Okamura C, Lin Q, Wang M, Shoemaker JE, et al. Repurposing the psoriasis drug Oxarol to an ointment adjuvant for the influenza vaccine. Int Immunol. 2020;32:499. doi:10.1093/intimm/dxaa012
- Urashima M, Mezawa H, Noya M, Camargo CA. Effects of vitamin D supplements on influenza A illness during the 2009 H1N1 pandemic: a randomized controlled trial. Food Funct. 2014;5:2365. doi:10.1039/c4fo00371c
- Khare D, Godbole NM, Pawar SD, Mohan V, Pandey G, et al. Calcitriol [1, 25[OH]2 D3] pre- and post-treatment suppresses inflammatory response to influenza A (H1N1) infection in human lung A549 epithelial cells. Eur J Nutr. 2013;52:1405. doi:10.1007/s00394-012-0449-7
- Urashima M, Segawa T, Okazaki M, Kurihara M, Wada Y, et al. Randomized trial of vitamin D supplementation to prevent seasonal influenza A in schoolchildren. Am J Clin Nutr. 2010;91:1255. doi:10.3945/ajcn.2009.29094
- Kriesel JD, Spruance J. Calcitriol (1,25-dihydroxy-vitamin D3) coadministered with influenza vaccine does not enhance humoral immunity in human volunteers. Vaccine. 1999;17:1883.
