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

Vitamin D In Reducing The Risk Of COVID 19

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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
Digestive

Digestive System Disorders: Common Causes, Symptoms, and Prevention Tips

The digestive system plays a vital role in overall health by breaking down food, absorbing nutrients and eliminating waste. When this system does not function properly, it can lead to discomfort, poor nutrition and chronic illness. Digestive system disorders are increasingly common due to modern lifestyles, dietary habits and stress. Understanding their causes, symptoms and prevention strategies is essential for maintaining long-term gut health.

Public health research shows that a large proportion of adults experience digestive symptoms at some point in their lives, yet many delay seeking care until problems become severe.

 

What Are Digestive System Disorders?

Digestive system disorders are conditions that affect:

  • the oesophagus
     

  • stomach
     

  • intestines
     

  • liver
     

  • pancreas
     

  • gallbladder
     

They may be temporary or chronic and range from mild functional issues to serious inflammatory or structural diseases.

 

Common Digestive System Disorders

Acid Reflux and GERD

Gastroesophageal reflux disease (GERD) occurs when stomach acid flows back into the oesophagus.

Symptoms include:

  • heartburn
     

  • chest discomfort
     

  • sour taste in mouth
     

  • difficulty swallowing
     

Long-term reflux can damage the oesophagus if untreated.

 

Irritable Bowel Syndrome (IBS)

IBS is a functional bowel disorder.

Symptoms include:

  • abdominal pain
     

  • bloating
     

  • diarrhoea or constipation
     

  • alternating bowel habits
     

Stress and diet often trigger symptoms.

 

Constipation

Constipation involves infrequent or difficult bowel movements.

Causes include:

  • low fibre intake
     

  • dehydration
     

  • sedentary lifestyle
     

Chronic constipation affects comfort and gut function.

 

Diarrhoea

Diarrhoea results from rapid bowel movements.

Common causes include:

  • infections
     

  • food intolerance
     

  • medication side effects
     

Persistent diarrhoea may lead to dehydration and nutrient loss.

 

Peptic Ulcer Disease

Ulcers are sores in the stomach or intestinal lining.

Symptoms include:

  • burning stomach pain
     

  • nausea
     

  • bloating
     

They are often linked to infections or long-term medication use.

 

Inflammatory Bowel Disease (IBD)

IBD includes conditions like Crohn’s disease and ulcerative colitis.

Symptoms include:

  • chronic diarrhoea
     

  • abdominal pain
     

  • weight loss
     

  • fatigue
     

IBD requires long-term medical management.

Common Symptoms of Digestive Disorders

Digestive system disorders often present with:

  • abdominal pain or cramps
     

  • bloating and gas
     

  • nausea or vomiting
     

  • constipation or diarrhoea
     

  • heartburn
     

  • unexplained weight changes
     

Symptoms may fluctuate and worsen with stress or poor diet.

 

Causes of Digestive System Disorders

Poor Dietary Habits

Diets high in:

  • processed foods
     

  • refined sugars
     

  • unhealthy fats
     

strain the digestive system and alter gut microbiota.

 

Stress and Mental Health

Chronic stress affects gut-brain communication, worsening digestive symptoms.

 

Infections

Bacterial, viral or parasitic infections disrupt gut function.

 

Food Intolerances

Lactose, gluten or other intolerances cause digestive distress.

 

Sedentary Lifestyle

Lack of physical activity slows digestion and bowel movement.

 

Medication Use

Certain medications irritate the stomach lining or alter gut flora.

 

Who Is at Higher Risk?

People at increased risk include:

  • individuals with poor diet
     

  • those under chronic stress
     

  • older adults
     

  • people with family history of gut disease
     

  • individuals with sedentary lifestyles
     

Early lifestyle correction reduces risk significantly.

 

Diagnosis of Digestive Disorders

Evaluation may include:

  • medical history
     

  • physical examination
     

  • blood tests
     

  • stool tests
     

  • imaging or endoscopy
     

Diagnosis depends on symptom severity and duration.

 

Treatment Approaches

Medical Management

Treatment varies by condition and may include:

  • acid suppressants
     

  • anti-inflammatory medications
     

  • probiotics
     

  • antibiotics when needed
     

 

Dietary Modifications

  • increase fibre intake
     

  • limit trigger foods
     

  • eat regular meals
     

  • avoid excessive alcohol
     

Diet plays a central role in gut health.

 

Lifestyle Changes

  • manage stress
     

  • exercise regularly
     

  • stay hydrated
     

  • maintain sleep routine
     

Healthy habits support digestive function.

 

Prevention Tips for Digestive Health

Eat a Balanced Diet

Include fruits, vegetables, whole grains and lean proteins.

 

Stay Hydrated

Water supports digestion and prevents constipation.

 

Manage Stress

Mindfulness and relaxation techniques improve gut-brain balance.

 

Be Physically Active

Movement stimulates bowel activity and gut motility.

 

Avoid Smoking and Excess Alcohol

These irritate the digestive tract and worsen symptoms.

 

Seek Early Medical Advice

Early care prevents complications and chronic disease.

 

Long-Term Impact of Ignoring Digestive Problems

Untreated digestive disorders may lead to:

  • nutrient deficiencies
     

  • chronic inflammation
     

  • poor quality of life
     

  • increased disease complications
     

Early intervention is more effective and less invasive.

 

When to Consult a Doctor

Medical advice is recommended if:

  • symptoms persist beyond weeks
     

  • pain is severe
     

  • blood appears in stool
     

  • unexplained weight loss occurs
     

Prompt evaluation ensures safe management.

 

Conclusion

Digestive system disorders are common but often underestimated health issues. Symptoms such as bloating, pain, constipation and heartburn may seem minor initially but can signal deeper problems if ignored. Understanding causes, recognising early symptoms and adopting preventive habits help protect digestive health. With timely care, balanced nutrition and healthy lifestyle choices, most digestive disorders can be effectively managed, allowing the digestive system to function smoothly and support overall wellbeing.

 

References

  • Indian Council of Medical Research (ICMR) – Digestive Health and Nutrition Reports

  • World Health Organization (WHO) – Digestive Disorders and Gut Health Guideline

  •  National Institute of Nutrition (NIN) – Dietary Fibre and Gut Health Researc

  •  Lancet – Gastrointestinal Disease and Prevention Studies

  •  Indian Journal of Gastroenterology – Digestive Disorder Research

  •  Statista – Digestive Health Trends and Lifestyle Factors

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