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.
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.
We explored how 25-hydroxyvitamin D3 (25OHD), a form of vitamin D, influences upper respiratory tract infections (URTIs), commonly known as colds. In a carefully designed clinical study, we followed 428 participants aged 45 to 74 over a 16-week period. They were randomly assigned to receive either 10 μg of 25OHD daily or a placebo, all while maintaining a double-blind setup to ensure accurate results.
Our findings revealed that those who took 25OHD had reduced duration and severity of their cold symptoms. Participants reported improvements in their overall quality of life during the bouts of URTI. By tracking the health of the participants through surveys designed to measure cold symptoms, we gathered valuable data that indicates vitamin D3 could play a helpful role in managing colds.
This suggests that incorporating vitamin D3 into our diets may be beneficial when we catch a cold, potentially leading to a quicker recovery. It’s a promising avenue for anyone looking to ease the discomfort and duration of these frustrating infections.
Read More
7
Vitamin D's limited cold impact
High-dose oral vitamin D supplementation for prevention of infections in children aged 0 to 59 months: a systematic review and meta-analysis.
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.
Read More
Most Useful Reviews
9
Impressive results
5 people found this helpful
Very effective D3! After long-term use from September to May, my husband and I took 1 capsule in the morning and evening with meals. The result: convenient 1000 dosage maintained prevention; I didn't get sick, just a runny nose occasionally. My lower back pain vanished! Thus, we will stock up for the cold period, ensuring we have Solgar D3. I’m very pleased with the quality, convenient dosages, and pricing! Thanks.
Read More
8
Energy boost
1 people found this helpful
My favourite in autumn and winter. After a doctor's advice, I started taking vitamin D3, 1 capsule in the morning and evening with meals. After three weeks, waking up became much easier, my mood improved, I felt more energetic, and drowsiness after lunch disappeared. I had always struggled during autumn and winter with lethargy, chronic fatigue, and frequent colds. Now I understand why and won't allow it to happen again. This "sunny" vitamin will accompany me from November to February. During the pandemic, my family takes vitamin Ester-C Plus with vitamin D3, as advised by the doctor. Remember to take dietary supplements under a doctor's supervision because excessive intake can be harmful. Look after your immunity—more positive emotions and health to everyone!
Read More
10
Winter without colds
We gave it to the kids during the winter season, and thankfully, this season passed without any colds. Heartfelt thanks to your wonderful company!
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.
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.
We explored how 25-hydroxyvitamin D3 (25OHD), a form of vitamin D, influences upper respiratory tract infections (URTIs), commonly known as colds. In a carefully designed clinical study, we followed 428 participants aged 45 to 74 over a 16-week period. They were randomly assigned to receive either 10 μg of 25OHD daily or a placebo, all while maintaining a double-blind setup to ensure accurate results.
Our findings revealed that those who took 25OHD had reduced duration and severity of their cold symptoms. Participants reported improvements in their overall quality of life during the bouts of URTI. By tracking the health of the participants through surveys designed to measure cold symptoms, we gathered valuable data that indicates vitamin D3 could play a helpful role in managing colds.
This suggests that incorporating vitamin D3 into our diets may be beneficial when we catch a cold, potentially leading to a quicker recovery. It’s a promising avenue for anyone looking to ease the discomfort and duration of these frustrating infections.
Read More
7
Vitamin D's limited cold impact
High-dose oral vitamin D supplementation for prevention of infections in children aged 0 to 59 months: a systematic review and meta-analysis.
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.
Read More
7
Vitamin D's role in Raynaud management
Serum vitamin B12 and D levels in children with Primary Raynaud Phenomenon: a retrospective cohort study.
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.
Read More
7
Vitamin D reduces cold symptoms
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.
We explored the effects of 25-hydroxyvitamin D (25OHD) on individuals experiencing upper respiratory tract infections (URTIs), commonly known as colds. In a well-structured study, participants with low vitamin D levels received either a daily dose of 10 micrograms of 25OHD or a placebo for a span of 16 weeks. The participants' symptoms were assessed using the Wisconsin Upper Respiratory Symptom Survey-21, focusing on how the vitamin impacted their cold symptoms.
Our findings showed that those taking 25OHD reported significant reductions in physical symptoms such as runny noses, sneezing, and head congestion compared to those on the placebo. Additionally, the quality of life scores improved for most symptoms, except for ease of breathing. However, it’s important to note that there was no significant difference in the total number of cold events or how often participants used medications like antibiotics or pain relievers.
Collectively, these results suggest that adequate intake of vitamin D can help ease cold symptoms, particularly those affecting the nose, and might enhance overall well-being when a cold strikes. This indicates that vitamin D may play a positive role in managing the discomfort associated with upper respiratory infections.
Very effective D3! After long-term use from September to May, my husband and I took 1 capsule in the morning and evening with meals. The result: convenient 1000 dosage maintained prevention; I didn't get sick, just a runny nose occasionally. My lower back pain vanished! Thus, we will stock up for the cold period, ensuring we have Solgar D3. I’m very pleased with the quality, convenient dosages, and pricing! Thanks.
Read More
8
Energy boost
1 people found this helpful
My favourite in autumn and winter. After a doctor's advice, I started taking vitamin D3, 1 capsule in the morning and evening with meals. After three weeks, waking up became much easier, my mood improved, I felt more energetic, and drowsiness after lunch disappeared. I had always struggled during autumn and winter with lethargy, chronic fatigue, and frequent colds. Now I understand why and won't allow it to happen again. This "sunny" vitamin will accompany me from November to February. During the pandemic, my family takes vitamin Ester-C Plus with vitamin D3, as advised by the doctor. Remember to take dietary supplements under a doctor's supervision because excessive intake can be harmful. Look after your immunity—more positive emotions and health to everyone!
Read More
10
Winter without colds
We gave it to the kids during the winter season, and thankfully, this season passed without any colds. Heartfelt thanks to your wonderful company!
Read More
9
Prevents illness
Excellent! I've been taking it daily for years, one capsule each morning. If I notice cold symptoms, I increase my dosage to five capsules daily. It helps a lot in preventing illness.
Read More
9
No illness
Excellent! I always take it at the start of autumn to maintain my immunity. I order for myself and my mother. The result: I haven’t been sick for two years, despite previously suffering from colds! I highly recommend it to everyone!
Cold is a term that refers to a state of low temperature, often associated with a perceptibly chilly environment or the sensation of being cool to the touch. Scientifically, cold is relative to the presence and movement of heat, which is a measure of energy within matter. In everyday terms, we experience cold through weather changes, such as during winter months, and it can also be described in the context of specific temperature ranges – for example, temperatures below 32 degrees Fahrenheit (0 degrees Celsius) generally signify freezing conditions, which can impact outdoor activities, personal comfort, and various ecological systems.
Moreover, the sensation of cold is not solely dependent on temperature; factors like humidity and wind chill can enhance the feeling of coldness. When discussing cold in terms of human health, prolonged exposure to cold conditions can lead to hypothermia or frostbite if body heat is not effectively maintained. Hence, it's crucial to dress appropriately and take necessary precautions during colder months to prevent adverse effects. Understanding the concept of cold can help individuals better prepare for seasonal changes and ensure their comfort and safety.
Vitamin D is a fat-soluble vitamin that's essential for maintaining healthy bones and teeth, supporting immune system function, and facilitating normal cell growth and development. It plays a crucial role in calcium absorption in the gut, which is vital for bone health. Unlike most vitamins, our bodies can produce Vitamin D when exposed to sunlight, specifically UVB rays, which is why it’s often referred to as the "sunshine vitamin." However, depending on your geographical location, lifestyle, and skin type, getting sufficient Vitamin D from the sun alone can be challenging, particularly during the winter months.
In addition to sunlight, Vitamin D can be obtained from certain foods such as fatty fish (like salmon and mackerel), fish liver oils, and fortified foods like milk and cereals. Some individuals may also consider supplements, especially if they're at risk for deficiency. Insufficient vitamin D levels are linked to various health issues, including rickets in children, osteomalacia in adults, and even an increased risk of chronic diseases. Regularly checking your vitamin D levels and consulting with a healthcare professional can help ensure you're meeting your needs for optimal health.
Vitamin D is often discussed in relation to immune health, and some studies suggest that it may play a role in reducing the risk of upper respiratory infections, including the common cold. Adequate levels of vitamin D might help enhance your immune response, potentially making your body more effective at fighting off infections. However, the evidence is not entirely conclusive, and while some individuals with low vitamin D levels may experience more frequent colds, it's important to consider that other factors also contribute to overall immunity, such as lifestyle and diet.
If you’re considering using vitamin D supplements to prevent or mitigate the effects of a cold, it’s always best to consult with a healthcare professional. They can provide tailored advice based on your specific health needs and possible deficiencies. While maintaining sufficient vitamin D levels can be beneficial for your immune system, it should not be seen as a guaranteed solution to avoid catching colds, especially during peak cold and flu seasons.
Based on user reviews, the timeframe for experiencing results from taking a vitamin D supplement for cold prevention can vary among individuals. Many users report noticeable improvements in their well-being and immunity within a few weeks. For instance, one reviewer noted a significant enhancement in mood and energy levels after just three weeks of consistent use, which helped alleviate symptoms of chronic fatigue and the tendency to catch colds during the colder months Read Review. Another user experienced substantial improvements after around 1.5 months, stating they had largely avoided colds in that time frame Read Review.
However, users emphasize that the results may not be immediate and suggest that it takes approximately one to two weeks before the effects become more apparent, such as enhanced immunity or prevention of cold symptoms Read Review. While individual experiences may vary, it is generally recommended to maintain a consistent supplementation routine to reap the full benefits and observe improvements in overall health during the cold season.
The role of vitamin D in managing common colds has garnered interest in scientific circles, with various studies exploring its potential benefits. A synthesis of several research pieces indicates that while vitamin D supplementation may not prevent colds outright, it appears to be associated with reduced severity and duration of cold symptoms. For instance, one randomized controlled trial revealed that participants receiving vitamin D experienced significant reductions in physical symptoms like runny noses and head congestion compared to those given a placebo, despite no considerable difference in the total number of cold occurrences [5].
Additionally, other research suggests that high-dose vitamin D might reduce the incidence of colds by up to 57%, with some limitations in certainty regarding cough and fever data [2]. Similarly, findings showed that adequate vitamin D levels led to a 40% lower likelihood of upper respiratory tract infections in physically active individuals such as military recruits [4]. Overall, while vitamin D supplementation seems promising in alleviating cold symptoms and possibly shortening the duration of illness, further studies are warranted to confirm these findings and establish optimal dosing.
Users have reported a variety of improvements in their symptoms after taking vitamin D3 supplements. Many individuals, like one user who took the supplement consistently from September to May, noted that they did not get sick during the cold season, experiencing only mild symptoms such as a runny nose Read Review. Others highlighted enhanced energy levels and mood improvements, with one reviewer feeling dramatically less fatigued and more alert after just three weeks of use. They expressed that this change helped alleviate chronic winter lethargy and reduced susceptibility to colds Read Review.
In addition to mood and energy enhancements, many users referred to a marked decrease in the frequency of colds. For example, a parent shared their satisfaction after giving vitamin D3 to their children, reporting that they passed the winter season without any colds Read Review. Another user highlighted a significant transformation, experiencing a considerable reduction in both severity and frequency of colds, improved bone health, and quicker recovery times Read Review. While many users have found success with these benefits, it is important to remember that individual results can vary significantly.
Users have expressed positive experiences when combining vitamin D3 supplements with other dietary aids, particularly vitamin C and zinc, for enhanced immunity during the cold season. One reviewer mentioned using vitamin D3 alongside vitamin C and zinc as advised by their doctor, noting an overall improvement in health and a successful avoidance of illness throughout winter Read Review. Another user confirmed this practice, stating their family took vitamin D3 together with zinc and vitamin C, contributing to a robust defense against colds and maintaining their well-being Read Review.
Additionally, those who intensified their vitamin D3 dosage at the onset of cold symptoms reported alleviated illness. For instance, a user increased their intake to five capsules per day when feeling unwell and found it significantly helpful in preventing more severe illness Read Review. Overall, the consensus among users is that combining vitamin D3 with other supplements can enhance immunity and overall health, making it a strategic move during colder months.
According to research, the optimal dose of Vitamin D for treating colds appears to lie around 800 IU to 1,000 IU daily. One study involving children indicated that those who consumed 800 IU daily for three months experienced fewer mild respiratory symptoms and quicker recovery from colds [1]. Additionally, another research noted that high-dose Vitamin D—specifically doses greater than 1,000 IU—reported significant reductions in cold occurrences and associated symptoms, showing a 57% decrease in colds and a 56% reduction in coughs [2].
However, caution is warranted as results can be variable and individual responses to supplementation may differ. While high doses seem to show promise in alleviating symptoms rather than preventing colds altogether, the evidence still calls for further exploration [2]. Overall, maintaining sufficient Vitamin D levels (generally above 50 nmol/L) may help ease cold symptoms, as suggested by findings showing those with adequate vitamin D were less likely to experience upper respiratory infections [4].
8
Energy boost
1 people found this helpful
My favourite in autumn and winter. After a doctor's advice, I started taking vitamin D3, 1 capsule in the morning and evening with meals. After three weeks, waking up became much easier, my mood improved, I felt more energetic, and drowsiness after lunch disappeared. I had always struggled during autumn and winter with lethargy, chronic fatigue, and frequent colds. Now I understand why and won't allow it to happen again. This "sunny" vitamin will accompany me from November to February. During the pandemic, my family takes vitamin Ester-C Plus with vitamin D3, as advised by the doctor. Remember to take dietary supplements under a doctor's supervision because excessive intake can be harmful. Look after your immunity—more positive emotions and health to everyone!
9
Drastically reduced colds
I take this vitamin for prophylaxis on my doctor's advice and have noticed substantial improvement over about 1.5 months. I used to catch colds frequently, but now that has changed. Even after encountering cold conditions, I’ve remained well. Importantly, I had a blood test for vitamin D levels after a break, and I'm pleased to find them within normal ranges. I maintain a schedule of two courses every two weeks but recommend monitoring the levels through testing.
6
Less illness
3 people found this helpful
To avoid getting sick, I struggled with immunity, often facing colds and sore throats. I discovered vitamin D3 after researching online and found I was deficient. I've been taking it for six months now, with some minor symptoms like temperature and cough, but I managed for just a couple of days without feeling bedridden. My mood has improved along with my nails, which no longer flake. Once I finish the jar (I take 2 capsules daily), I'll get tested and continue at a reduced dosage for prevention. The results aren't immediate but become noticeable after a week or two. Overall, I highly recommend this!
9
Impressive results
5 people found this helpful
Very effective D3! After long-term use from September to May, my husband and I took 1 capsule in the morning and evening with meals. The result: convenient 1000 dosage maintained prevention; I didn't get sick, just a runny nose occasionally. My lower back pain vanished! Thus, we will stock up for the cold period, ensuring we have Solgar D3. I’m very pleased with the quality, convenient dosages, and pricing! Thanks.
10
Winter without colds
We gave it to the kids during the winter season, and thankfully, this season passed without any colds. Heartfelt thanks to your wonderful company!
9
Reduced colds significantly
These vitamins have truly transformed my life. I never imagined that one small vitamin a day could enhance my quality of life so much. Previously, I endured frequent colds, around eight times a year, often with complications. During the cold seasons, my bones ached. However, since I've started taking these yellow capsules, I very rarely contract colds, and if I do, they are mild without complications. My bones no longer ache, I recover quicker, and my hair is now thicker and stronger. After nearly two years of taking these vitamins, I’m consistently amazed at their benefits.
9
Prevention and mood
A family favourite - we take this vitamin D3 to prevent colds and boost our mood from November until spring. It’s perfectly absorbed, and we consume it alongside zinc and vitamin C, one capsule daily with breakfast.
9
Prevents illness
Excellent! I've been taking it daily for years, one capsule each morning. If I notice cold symptoms, I increase my dosage to five capsules daily. It helps a lot in preventing illness.
7
Vitamin D reduces cold symptoms
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.
We explored the effects of 25-hydroxyvitamin D (25OHD) on individuals experiencing upper respiratory tract infections (URTIs), commonly known as colds. In a well-structured study, participants with low vitamin D levels received either a daily dose of 10 micrograms of 25OHD or a placebo for a span of 16 weeks. The participants' symptoms were assessed using the Wisconsin Upper Respiratory Symptom Survey-21, focusing on how the vitamin impacted their cold symptoms.
Our findings showed that those taking 25OHD reported significant reductions in physical symptoms such as runny noses, sneezing, and head congestion compared to those on the placebo. Additionally, the quality of life scores improved for most symptoms, except for ease of breathing. However, it’s important to note that there was no significant difference in the total number of cold events or how often participants used medications like antibiotics or pain relievers.
Collectively, these results suggest that adequate intake of vitamin D can help ease cold symptoms, particularly those affecting the nose, and might enhance overall well-being when a cold strikes. This indicates that vitamin D may play a positive role in managing the discomfort associated with upper respiratory infections.
7
Vitamin D's limited cold impact
High-dose oral vitamin D supplementation for prevention of infections in children aged 0 to 59 months: a systematic review and meta-analysis.
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.
8
Vitamin D reduces cold severity
Influence of Vitamin D Supplementation by Simulated Sunlight or Oral D3 on Respiratory Infection during Military Training.
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.
5
Vitamin D and cold symptoms
The Effects of Vitamin D Supplementation on Respiratory Infections in Children under 6 Years Old: A Systematic Review.
We explored the effects of vitamin D supplementation on respiratory infections, particularly colds, in children under six years old. By examining various studies published until February 2023, we observed diverse findings, with some studies reporting benefits while others found no significant advantage. Overall, eight studies were included, with a total of 2,189 children assessed.
While a few studies indicated that low vitamin D levels might be linked to an increased risk of respiratory infections, only one study specifically noted that children who took 800 IU of vitamin D daily for three months experienced fewer mild respiratory symptoms and recovered more quickly. However, a significant number of studies showed no notable differences in the rates or severity of colds when vitamin D supplementation was used.
In essence, the evidence regarding vitamin D's role in preventing or effectively treating colds in young children is still unclear. We did find some indications that certain doses, like 80 IU/kg/day, may help reduce acute respiratory infection risks, but most research highlighted only minor benefits, such as quicker recovery rather than preventing infections. Variability in study design and supplementation protocols contributed to these inconclusive results, highlighting the need for further research.
References
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. doi: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. doi: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. doi: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. doi: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. doi:10.3390/nu12123769
Shimizu Y, Ito Y, Yui K, Egawa K, Orimo H. Intake of 25-Hydroxyvitamin D3 Reduces Duration and Severity of Upper Respiratory Tract Infection: A Randomized, Double-Blind, Placebo-Controlled, Parallel Group Comparison Study. J Nutr Health Aging. 2018;22:491. doi:10.1007/s12603-017-0952-x