• 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
effective

Anemia Diet Plan: What to Eat to Improve Hemoglobin Levels Naturally

Anemia is one of the most widespread nutritional disorders in India, affecting people across age groups. According to NFHS-5 and ICMR data, more than half of Indian women and a significant proportion of men suffer from anemia. While supplements are sometimes required, a structured anemia diet plan plays a central role in preventing and managing the condition.

Anemia occurs when the body lacks sufficient healthy red blood cells or hemoglobin to carry oxygen efficiently. Nutrition is the foundation of hemoglobin production, making dietary correction essential.

 

Understanding the Nutritional Causes of Anemia

Anemia commonly results from deficiencies of:

  • iron

  • vitamin B12

  • folate

Each nutrient plays a specific role in red blood cell formation.

 

Iron: The Core Nutrient in Anemia

Iron is a key component of hemoglobin.

Iron deficiency leads to:

  • fatigue

  • weakness

  • pale skin

  • shortness of breath

ICMR identifies iron deficiency as the leading cause of anemia in India.

 

Types of Dietary Iron

Heme Iron

Found in animal foods and absorbed efficiently.

Sources include:

  • eggs

  • fish

  • chicken

  • liver

 

Non-Heme Iron

Found in plant-based foods and absorbed less efficiently.

Sources include:

  • spinach

  • lentils

  • chickpeas

  • jaggery

  • dates

Vitamin C improves non-heme iron absorption.

 

Role of Vitamin B12 in Anemia

Vitamin B12 is essential for red blood cell maturation.

Deficiency causes:

  • megaloblastic anemia

  • nerve symptoms

  • memory issues

Vegetarians are at higher risk due to limited dietary sources.

 

Role of Folate

Folate supports:

  • DNA synthesis

  • red blood cell formation

Low folate intake worsens anemia, especially during pregnancy.

 

Foods to Include in an Anemia Diet Plan

Iron-Rich Foods

  • green leafy vegetables (spinach, amaranth)

  • legumes and pulses

  • dates, raisins and figs

  • jaggery

  • red meat and eggs

 

Vitamin C-Rich Foods

  • citrus fruits

  • guava

  • tomatoes

  • bell peppers

These enhance iron absorption.

 

Vitamin B12 Sources

  • milk and dairy products

  • eggs

  • fish

  • fortified cereals

 

Folate-Rich Foods

  • green leafy vegetables

  • beans and peas

  • peanuts

  • whole grains

 

Sample Daily Anemia Diet Plan

Breakfast

  • vegetable omelette or sprouted moong

  • citrus fruit or guava

 

Mid-Morning

  • soaked raisins or dates

  • lemon water

 

Lunch

  • brown rice or roti

  • dal or chickpeas

  • green leafy vegetable sabzi

  • salad with lemon dressing

 

Evening Snack

  • roasted peanuts or chana

  • fruit rich in vitamin C

 

Dinner

  • vegetable curry with paneer or fish

  • whole wheat roti

  • lightly cooked greens

 

Bedtime

  • warm milk if tolerated

 

Foods That Reduce Iron Absorption

Certain foods interfere with iron absorption:

  • tea and coffee

  • excess calcium

  • highly processed foods

These should be avoided close to iron-rich meals.

 

Special Considerations for Women

Women require more iron due to:

  • menstruation

  • pregnancy

  • lactation

NFHS-5 highlights anemia as a major women’s health concern in India.

 

Anemia in Men and Older Adults

In men and elderly individuals, anemia may signal:

  • nutritional deficiency

  • chronic disease

  • gastrointestinal issues

Dietary correction should be combined with medical evaluation.

 

When Diet Alone Is Not Enough

Diet may not be sufficient if:

  • anemia is severe

  • absorption is impaired

  • chronic illness is present

In such cases, supplements or treatment of underlying causes is required.

 

Importance of Regular Blood Tests

Monitoring hemoglobin helps:

  • assess improvement

  • guide dietary adjustments

  • prevent recurrence

Preventive checkups are essential for high-risk groups.

 

Lifestyle Factors That Support Recovery

Along with diet:

  • adequate sleep

  • stress management

  • regular physical activity

support blood health and recovery.

 

Preventing Anemia Long-Term

Long-term prevention includes:

  • balanced meals

  • iron-rich cooking methods

  • avoiding excessive junk food

  • periodic screening

WHO and NITI Aayog emphasize nutrition education as a preventive strategy.

 

Conclusion

A well-structured anemia diet plan is the cornerstone of improving hemoglobin levels and restoring energy. By including iron-rich foods, supporting nutrients like vitamin B12 and folate, and improving absorption through smart food combinations, anemia can be effectively managed and prevented. Early dietary intervention, supported by regular health monitoring, helps avoid long-term complications and improves overall quality of life.

 

References

  • Indian Council of Medical Research (ICMR) – Anemia and Micronutrient Deficiency Reports

  • National Family Health Survey (NFHS-5) – Anemia Prevalence Data

  • World Health Organization (WHO) – Nutrition and Anemia Guidelines

  • Lancet – Micronutrient Deficiency and Public Health Research

  • NITI Aayog – Poshan Abhiyaan and Nutrition Policy Reports

  • Statista – Nutrition and Health Trends in 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