• Published on: Apr 17, 2020
  • 4 minute read
  • By: Dr Rajan Choudhary

Vitamin D In Reducing The Risk Of COVID 19

  • WhatsApp share link icon
  • copy & share link icon
  • twitter share link icon
  • facebook share link icon

Why Vitamin D is the only supplement we will recommend for you.

Most of our blogs have looked at theories posted on social media, and shown how they are usually not true, or have no factual basis behind them. But here we will show some evidence that supports something truly interesting, especially during the time of this pandemic.

For a number of years research has shown a possible link between vitamin D and illnesses, specifically respiratory infections. In our previous blogs we have shown that vitamin supplementation is unnecessary, except for vitamin D. Here we will show why supplementation may be in your best interest for reducing the risk of COVID.

Now I’ll be honest. Vitamin D and immunity was not something we were taught at medical school, or in medical practice. The fact that such a large amount of research exists on this topic is certainly interesting, and whilst researching this topic I have certainly learnt a lot myself, enough to change my own medical practice. And it is because of the high quality of evidence present that I feel confident in supporting the claims below.

SUMMARY

  • Many people are low in Vitamin D due to various risk factors (see our blog on vitamin D)
  • Vitamin D appears to have a role in modulating immune function
  • Low Vitamin D levels appear to increase the severity of autoimmune disorders
  • Low Vitamin D levels appear to increase the risk of getting respiratory infections
  • Vitamin D supplementation appears to reduce the risk of getting respiratory infections
  • Those who are at risk of having low vitamin D should take low dose supplementations.

If you want the good stuff, skip to the section on SUPPLEMENTATION

IMMUNE FUNCTIONS

As we’ve discussed, vitamin D is key in maintaining the right balance of calcium, ensuring the right amount is taken up from the food we eat, integrated into our bones, and removed in our urine if not required. We know that there are some people who are at risk of vitamin D deficiency, and this is more common in countries closer to the poles and with cloudy weather.

But there also appears to be a role for vitamin D in modulating the immune system. We have found many more cells in our body other than bone, intestine and kidney that possess the vitamin D receptor. These include immune cells, and one role may be to promote proliferation of these cells as well as promote their protective immunity.

AUTOIMMUNE

Due to its role in immune function, studies have been performed to see whether there is a link between autoimmune diseases and vitamin D. Common autoimmune disorders (and the organs the affect) include multiple sclerosis (nerves), rheumatoid arthritis (joints), diabetes mellitus (pancreas), inflammatory bowel disease (bowels) and systemic lupus erythematous (the entire body). All of these diseases lead to loss in function of an organ or system as the immune system recognises the organ as an “invader” and begins to destroy it.

One study looked at 161 patients with early forms of autoimmune diseases over 2 years. Out of them, 35 went on to develop full blown autoimmune disorders (like rheumatoid and lupus). Whilst the two groups of patients were mostly similar, vitamin D was noticeably lower in the group that progressed to disease. But this is one study, with a small number of patients.

Other studies have looked at vitamin D levels in patients across the globe, and the majority of them have shown there to be a correlation between low vitamin D or severe deficiency, and the severity of autoimmune disorder they have. We will not go into them in detail because this is beyond the scope of this blog, but it certainly is interesting and supports this new role for vitamin D.

RESPIRATORY INFECTIONS

We have unknowingly tried to use Vitamin D to treat infections prior to the advent of antibiotics. A common treatment for tuberculosis was to send patients to sanatoriums, where treatments included exposure to sunlight, and provision of cod liver oil, a rich source of vitamin D.

Large population studies done in the 1980s and 1990s involving 19,000 people showed that those with low vitamin D levels were more likely to self report recent upper respiratory tract infections than those with normal levels. This was true even if age, gender, season and race were accounted for. Similar studies have shown similar results when looking at rates of influenza, bacterial vaginosis and HIV.

Normally we are very skeptical with such studies, and look for weaknesses in their methodology and conclusions. After all, we could just cherry pick the studies that show a benefit. Furthermore, just because there is a trend with vitamin D levels and infection, this does not imply a direct link. More evidence is required. However, the fact 19,000 people were surveyed provides this study with good statistical power, and lends it validity. But lets look for more.

SUPPLEMENTATION

Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data – Martineau 2017, British Medical Journal

A systematic review and meta analysis is the highest level of evidence in the realm of medical research. It is the absolute pinnacle of thorough research, looking and comparing other studies with very close scrutiny to see whether we have conducted enough research worldwide to support a theory. In this case this systematic review was published in the British Medical Journal, a highly reputable source that again scrutinises any study submitted thoroughly before accepting it for publication. In my eyes, this is some of the best evidence we will have on this topic. And it is a far sight better than any WhatsApp forwards.

So what does this say?

Vitamin D supplementation was safe and it protected against acute respiratory tract infection overall. Patients who were very vitamin D deficient and those not receiving bolus doses experienced the most benefit.

I don’t think I could have summarised it better myself. If you wish to read the study yourself you can use this link: https://www.bmj.com/content/356/bmj.i6583 Vitamin D supplementation to prevent acute respiratory tract infections

WHAT DOES THIS MEAN FOR ME?

If you are someone who may be at risk of vitamin D deficiency, then low dose supplements (NOT treatment dose) may be beneficial in reducing the risk of getting a respiratory infection. Since COVID is caused by a respiratory virus, we can extrapolate that Vitamin D supplementations may reduce your risk of getting COVID. This is not a cure, and it is not a guaranteed protection. If you already have a balanced diet and are not low in Vit D, it may be less beneficial.

Dr Rajan Choudhary, UK, Chief Product Officer, Second Medic Inc

www.secondmedic.com

Read Blog
Monthly Health Survey via SecondMedic App: A Smarter Approach to Preventive Healthcare

Monthly Health Survey via SecondMedic App: A Smarter Approach to Preventive Healthcare

Healthcare is gradually shifting from reactive treatment to proactive prevention. Traditional health models rely heavily on annual checkups or medical visits only after symptoms become severe. However, many chronic and lifestyle-related conditions develop silently over time. The Monthly Health Survey via the SecondMedic App addresses this gap by enabling continuous health monitoring and early risk identification.

According to the Indian Council of Medical Research (ICMR) and NITI Aayog, early detection and preventive care are critical to reducing the growing burden of non-communicable diseases in India. Digital health tools play a key role in achieving this shift.

What Is the Monthly Health Survey?

The Monthly Health Survey is a structured digital questionnaire delivered through the SecondMedic App. It captures key health indicators such as:

  • recurring symptoms
     

  • lifestyle habits
     

  • stress and sleep patterns
     

  • nutrition and activity levels
     

  • chronic condition markers
     

By repeating the survey monthly, subtle health trends become visible.

 

Why Monthly Health Tracking Matters

Annual Checkups Miss Gradual Changes

Many health issues develop slowly. Annual tests may appear normal while symptoms quietly progress between visits.

Monthly surveys:

  • detect early warning signs
     

  • capture symptom patterns
     

  • identify lifestyle-related risks
     

 

Health Is Dynamic, Not Static

Stress, sleep, diet and activity fluctuate monthly. Regular tracking reflects real-life health variation more accurately than isolated tests.

 

How the Monthly Health Survey Works

Each month, users answer a guided set of questions related to:

  • physical symptoms
     

  • mental wellbeing
     

  • lifestyle behaviours
     

  • known medical conditions
     

The app analyses responses to highlight:

  • risk trends
     

  • symptom persistence
     

  • areas needing attention
     

This structured approach simplifies health awareness.

 

Key Health Areas Covered

Symptom Monitoring

Persistent fatigue, headaches, breathlessness or digestive issues are tracked across months to identify patterns.

 

Lifestyle Risk Factors

The survey captures:

  • sedentary behaviour
     

  • sleep quality
     

  • stress levels
     

  • dietary habits
     

These factors strongly influence long-term health outcomes.

 

Chronic Disease Indicators

For individuals with diabetes, hypertension or thyroid conditions, monthly monitoring supports better disease control and early escalation.

 

Role in Preventive Healthcare

Preventive healthcare focuses on stopping disease before complications arise.

Monthly health surveys support prevention by:

  • identifying risks early
     

  • prompting timely consultations
     

  • supporting lifestyle modification
     

  • reducing emergency care needs
     

WHO and NITI Aayog both highlight digital monitoring as a cornerstone of preventive health systems.

 

Benefits for Individuals

Early Awareness

Users become aware of health changes before symptoms become severe.

 

Empowered Decision-Making

Access to regular health insights encourages proactive lifestyle choices.

 

Reduced Anxiety

Structured tracking reduces uncertainty and fear about unexplained symptoms.

 

Better Doctor Consultations

Survey data provides doctors with a clearer health history, improving consultation quality.

 

Benefits for Chronic Care Management

For chronic conditions, consistency is key.

Monthly surveys help:

  • track symptom control
     

  • identify early deterioration
     

  • support medication adherence
     

  • reduce complications
     

This continuous loop improves long-term outcomes.

 

Data-Driven Personalised Care

The survey supports personalised care by:

  • tailoring recommendations
     

  • prioritising high-risk users
     

  • guiding preventive interventions
     

This approach moves healthcare from generic advice to individualised guidance.

 

Privacy and Responsible Use

Health data is sensitive.

The survey framework is designed to:

  • collect only relevant information
     

  • support medical decision-making
     

  • maintain confidentiality
     

Responsible data use builds trust and long-term engagement.

 

Why Digital Surveys Are Effective in India

India’s healthcare challenges include:

  • large population
     

  • limited access to preventive care
     

  • high lifestyle disease burden
     

Digital surveys overcome barriers by:

  • being accessible anywhere
     

  • requiring minimal time
     

  • enabling large-scale preventive monitoring
     

This scalability makes them highly impactful.

 

Integration with Broader Health Ecosystems

Monthly health surveys work best when integrated with:

  • medical consultations
     

  • diagnostic services
     

  • preventive checkups
     

  • digital health records
     

Integration ensures continuity of care.

 

Long-Term Impact on Healthcare Outcomes

Over time, regular health tracking leads to:

  • earlier diagnoses
     

  • reduced hospitalisations
     

  • better chronic disease control
     

  • lower healthcare costs
     

  • improved quality of life
     

Lancet studies show that continuous monitoring significantly improves preventive outcomes.

 

Who Should Use a Monthly Health Survey?

  • adults over 30
     

  • individuals with chronic conditions
     

  • people with high-stress lifestyles
     

  • those focusing on preventive health
     

  • corporate wellness participants
     

Proactive monitoring benefits all age groups.

 

Conclusion

The Monthly Health Survey via the SecondMedic App represents a modern, preventive approach to healthcare. By capturing health trends regularly rather than annually, it empowers individuals to act early, supports doctors with better insights and reduces the burden of advanced disease. In an era where prevention is the most effective medicine, monthly health surveys transform awareness into action and data into healthier lives.

 

References

  • Indian Council of Medical Research (ICMR) – Preventive Healthcare and Early Detection Report

  •  NITI Aayog – Digital Health and Preventive Care Strateg

  •  World Health Organization (WHO) – Digital Health Monitoring Guideline

  •  Lancet – Preventive Healthcare and Continuous Monitoring Studies

  • National Health Authority – Digital Health Mission Indi

  •  Statista – Digital Health App Adoption Trends India

See all

Live Doctor consultation
Live Doctor Chat

Download Our App & Get Consultation from anywhere.

App Download
call icon for mobile number calling and whatsapp at secondmedic