'
SCIENTIFIC SCORE
Possibly Effective
Based on 7 Researches
7.9
USERS' SCORE
Good
Based on 4 Reviews
8.7
Supplement Facts
Serving Size: 1 Soft Gel
Amount Per Serving
%DV
Vitamin D (as cholecalciferol)
100 mcg (4,000 IU)
500%

Top Medical Research Studies

8
Vitamin D reduces cold severity
Influence of Vitamin D Supplementation by Simulated Sunlight or Oral D3 on Respiratory Infection during Military Training.
Highly relevant vitamin D study
We explored the connection between vitamin D levels and the frequency of upper respiratory tract infections (URTI) in physically active individuals throughout different seasons. In our research, we observed over 1,600 military recruits during their basic training, noting that only 21% were vitamin D sufficient during winter. Alarmingly, those who had sufficient vitamin D levels were found to be 40% less likely to experience URTIs compared to their deficient counterparts, suggesting that maintaining adequate vitamin D may be crucial for better respiratory health during demanding training periods.

Building on these findings, we conducted a follow-up study with 250 recruits, where we implemented various vitamin D supplementation strategies. Participants received either a placebo, simulated sunlight exposure, or oral vitamin D3 supplementation. The results were promising: vitamin D helped alleviate the severity of URTI symptoms and significantly reduced the number of days experiencing a cold. Notably, both sunlight and dietary supplementation were equally effective in boosting vitamin D levels and improving outcomes.

Overall, achieving vitamin D sufficiency can markedly reduce the burden of URTIs, particularly in physically demanding scenarios such as military training.
Read More
8
Vitamin D3 aids cold recovery
Intake of 25-Hydroxyvitamin D3 Reduces Duration and Severity of Upper Respiratory Tract Infection: A Randomized, Double-Blind, Placebo-Controlled, Parallel Group Comparison Study.
Highly relevant to respiratory health
We explored whether taking 25-hydroxyvitamin D3, a form of vitamin D, could have a positive impact on upper respiratory tract infections (URTIs), commonly known as colds. To do this, we conducted a randomized, double-blind, placebo-controlled study at clinics in Japan, involving 428 participants aged between 45 and 74 years.

Participants were divided into two groups: one received a daily dose of 10 micrograms of vitamin D3, while the other group received a placebo for 16 weeks. We monitored the frequency of URTIs, their severity, the participants’ quality of life, and the duration of the infections.

Our findings revealed that those who took vitamin D3 experienced shorter durations of URTIs, less severe symptoms, and better quality of life during their illness compared to those on the placebo. This suggests that vitamin D3 may help mitigate the discomfort associated with colds and potentially make us feel better more quickly when we are sick.
Read More
8
Vitamin D’s role in cold prevention
Self-Care for Common Colds: The Pivotal Role of Vitamin D, Vitamin C, Zinc, and in Three Main Immune Interactive Clusters (Physical Barriers, Innate and Adaptive Immunity) Involved during an Episode of Common Colds-Practical Advice on Dosages and on the Time to Take These Nutrients/Botanicals in order to Prevent or Treat Common Colds.
Moderate relevance to vitamin D
We examined the role of vitamin D in managing common colds, delving into how it interacts with our immune system to potentially lessen the severity and duration of symptoms. The study highlighted that individuals with vitamin D deficiency, as well as those not receiving large doses, are more likely to benefit from vitamin D supplementation during cold episodes.

Findings suggest that vitamin D might act as a protective agent against common colds overall. Taking vitamin D regularly could help fortify our immune response, which plays a crucial part in fighting off the viruses responsible for colds. The research points towards the idea that maintaining adequate vitamin D levels may offer significant advantages for keeping our immune system vigilant.

However, it’s essential to approach this information with a measure of caution, as further research is necessary to draw definitive conclusions. Overall, encouraging patients to consider vitamin D as a part of their cold prevention strategy seems promising.
Read More

Most Useful Reviews

10
Significant immune boost
Since adding this supplement to my routine, I've noticed a significant improvement in my immune health. I've not experienced a cold since starting it, which feels like a major success for me.
Read More
9.5
Remarkable cold reduction
I started taking these vitamins to bolster my immune system and found I catch colds less often. The results have been truly amazing, and I'm exceptionally pleased I made this purchase.
Read More
8.8
Less prone to colds
I take Vitamin D3 daily, even in summer, due to a significant deficiency. Whenever I stop the supplements, my Vitamin D levels drop. I believe that taking 4000 to 5000 IU daily benefits me greatly. Since I began supplementing, I've been much less susceptible to colds and flu, and my nails and skin have improved. This is my first time purchasing Carlson's Vitamin D3, as I trust this brand based on my prior experience with their Omega-3 products.
Read More

Medical Researches

SCIENTIFIC SCORE
Possibly Effective
Based on 7 Researches
7.9
8
Vitamin D reduces cold severity
Influence of Vitamin D Supplementation by Simulated Sunlight or Oral D3 on Respiratory Infection during Military Training.
Highly relevant vitamin D study
We explored the connection between vitamin D levels and the frequency of upper respiratory tract infections (URTI) in physically active individuals throughout different seasons. In our research, we observed over 1,600 military recruits during their basic training, noting that only 21% were vitamin D sufficient during winter. Alarmingly, those who had sufficient vitamin D levels were found to be 40% less likely to experience URTIs compared to their deficient counterparts, suggesting that maintaining adequate vitamin D may be crucial for better respiratory health during demanding training periods.

Building on these findings, we conducted a follow-up study with 250 recruits, where we implemented various vitamin D supplementation strategies. Participants received either a placebo, simulated sunlight exposure, or oral vitamin D3 supplementation. The results were promising: vitamin D helped alleviate the severity of URTI symptoms and significantly reduced the number of days experiencing a cold. Notably, both sunlight and dietary supplementation were equally effective in boosting vitamin D levels and improving outcomes.

Overall, achieving vitamin D sufficiency can markedly reduce the burden of URTIs, particularly in physically demanding scenarios such as military training.
Read More
8
Vitamin D’s role in cold prevention
Self-Care for Common Colds: The Pivotal Role of Vitamin D, Vitamin C, Zinc, and in Three Main Immune Interactive Clusters (Physical Barriers, Innate and Adaptive Immunity) Involved during an Episode of Common Colds-Practical Advice on Dosages and on the Time to Take These Nutrients/Botanicals in order to Prevent or Treat Common Colds.
Moderate relevance to vitamin D
We examined the role of vitamin D in managing common colds, delving into how it interacts with our immune system to potentially lessen the severity and duration of symptoms. The study highlighted that individuals with vitamin D deficiency, as well as those not receiving large doses, are more likely to benefit from vitamin D supplementation during cold episodes.

Findings suggest that vitamin D might act as a protective agent against common colds overall. Taking vitamin D regularly could help fortify our immune response, which plays a crucial part in fighting off the viruses responsible for colds. The research points towards the idea that maintaining adequate vitamin D levels may offer significant advantages for keeping our immune system vigilant.

However, it’s essential to approach this information with a measure of caution, as further research is necessary to draw definitive conclusions. Overall, encouraging patients to consider vitamin D as a part of their cold prevention strategy seems promising.
Read More
8
Vitamin D3 aids cold recovery
Intake of 25-Hydroxyvitamin D3 Reduces Duration and Severity of Upper Respiratory Tract Infection: A Randomized, Double-Blind, Placebo-Controlled, Parallel Group Comparison Study.
Highly relevant to respiratory health
We explored whether taking 25-hydroxyvitamin D3, a form of vitamin D, could have a positive impact on upper respiratory tract infections (URTIs), commonly known as colds. To do this, we conducted a randomized, double-blind, placebo-controlled study at clinics in Japan, involving 428 participants aged between 45 and 74 years.

Participants were divided into two groups: one received a daily dose of 10 micrograms of vitamin D3, while the other group received a placebo for 16 weeks. We monitored the frequency of URTIs, their severity, the participants’ quality of life, and the duration of the infections.

Our findings revealed that those who took vitamin D3 experienced shorter durations of URTIs, less severe symptoms, and better quality of life during their illness compared to those on the placebo. This suggests that vitamin D3 may help mitigate the discomfort associated with colds and potentially make us feel better more quickly when we are sick.
Read More
8
Vitamin D aids immune response
Immunological aspects of sport nutrition.
Relevant to vitamin D effects
We observed the important role that vitamin D plays in maintaining a healthy immune system, particularly regarding the common cold. Research indicates that vitamin D may help limit the incidence and duration of infections, which can be especially beneficial for athletes.

Notably, many individuals, including athletes, often exhibit low vitamin D levels, especially during winter months. This deficiency may increase the risk of catching common illnesses like colds and flu.

While studies suggest that vitamin D can have a positive effect on immune function, the evidence around its effectiveness specifically for the common cold isn't overwhelming. We found that a well-balanced approach to nutrition, rather than relying solely on supplements, is essential for optimal immune health in athletes.
Read More
8
Efficacy of micronutrients on colds
[Dietary efficacy of a micronutrient combination in patients with recurrent upper respiratory tract infections. Results of a placebo-controlled double-blind study].
Vitamin D's role unclear
We explored how a combination of vitamins and minerals, including vitamin D, could potentially influence the frequency and severity of common colds among individuals who frequently suffer from upper respiratory infections. In a well-structured study involving 192 participants, we conducted a randomized, placebo-controlled, double-blind trial that lasted for 16 weeks.

Throughout the trial, we monitored a range of factors, including the number and intensity of cold symptoms. Notably, those who received the micronutrient combination, which encompassed vitamins like C and D as well as other essential nutrients, reported significant improvements compared to participants who received a placebo.

Our findings revealed that patients who were initially experiencing a severe common cold saw a notable decrease in their symptoms. Additionally, individuals under 45 years who took the micronutrient blend were less likely to miss work during cold episodes. Importantly, those with initially low levels of vitamin D and C reported fewer colds while taking the supplements.

While vitamin D played a role alongside other micronutrients in improving cold symptoms and reducing infection frequencies, we must recognize that it was part of a broader combination. Thus, while we observed promising results, the specific contribution of vitamin D alone remains challenging to delineate.
Read More

User Reviews

USERS' SCORE
Good
Based on 4 Reviews
8.7
10
Significant immune boost
Since adding this supplement to my routine, I've noticed a significant improvement in my immune health. I've not experienced a cold since starting it, which feels like a major success for me.
9.5
Remarkable cold reduction
I started taking these vitamins to bolster my immune system and found I catch colds less often. The results have been truly amazing, and I'm exceptionally pleased I made this purchase.
8.8
Helpful for immunity
I began taking this fat-soluble vitamin two years ago at a dosage of 2000 to 5000 IU daily. Research suggests it can enhance immune function and lower the risk of infections. Since starting, I haven't caught a cold, apart from the covid infection. I initially used the Now brand but switched to this one due to its variety of dosages and the moderate size of the soft capsules, which are easy to swallow. I find it very effective.
Read More
8.8
Less prone to colds
I take Vitamin D3 daily, even in summer, due to a significant deficiency. Whenever I stop the supplements, my Vitamin D levels drop. I believe that taking 4000 to 5000 IU daily benefits me greatly. Since I began supplementing, I've been much less susceptible to colds and flu, and my nails and skin have improved. This is my first time purchasing Carlson's Vitamin D3, as I trust this brand based on my prior experience with their Omega-3 products.
Read More
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