• 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

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Why do you wake up tired

Why Do You Wake Up Tired Even After 8 Hours Sleep?

Getting 8 hours of sleep is often seen as the gold standard for good health. But what if you’re still waking up feeling groggy, exhausted, and low on energy—despite clocking in those 8 hours? If that sounds like you, you’re not alone.

In this blog, we’ll explore why you wake up tired even after 8 hours sleep, the possible reasons behind it, and simple ways to fix the issue so you can start your day refreshed and energized.

 

Sleep Quantity vs. Sleep Quality

It’s important to understand that sleep is not just about how long you sleep, but how well you sleep.

There are different stages of sleep your body goes through:

  • Light Sleep (Stage 1 & 2)
     

  • Deep Sleep (Stage 3)
     

  • REM Sleep (Stage 4) – where dreams and memory processing happen
     

If your sleep is constantly interrupted, or if you don’t get enough deep or REM sleep, your body and brain won’t be fully rested—even after 8 hours in bed.

 

7 Common Reasons You Wake Up Tired After a Full Night’s Sleep

1. Poor Sleep Quality

You may be lying in bed for 8 hours, but if your sleep is light or frequently interrupted, it won’t be refreshing. Common reasons include:

  • Noisy environment
     

  • Uncomfortable mattress or pillow
     

  • Room too hot or too cold
     

  • Lights or electronics nearby
     

Fix: Try blackout curtains, keep the room cool and dark, and follow a fixed bedtime routine.

 

2. Undiagnosed Sleep Disorders

Conditions like sleep apnea, restless leg syndrome, or insomnia can reduce sleep quality without you even realizing it.

Sleep apnea, for example, causes you to stop breathing for short periods during sleep. You may not wake up fully, but your body doesn’t get enough oxygen—leading to morning tiredness and brain fog.

Fix: If your partner says you snore heavily or you often wake up gasping for air, consult a doctor for a sleep study.

 

3. Too Much Screen Time at Night

Smartphones, laptops, and TVs emit blue light, which blocks melatonin—a hormone that helps you fall asleep.

If you scroll Instagram or binge-watch shows late at night, your brain might stay active even after you fall asleep.

Fix: Stop using screens 1 hour before bedtime. Use night mode or blue light filters if necessary.

 

4. Eating or Drinking Close to Bedtime

Heavy meals or caffeine before bed can disturb your sleep by causing indigestion, bloating, or increased alertness.

Fix: Avoid caffeine after 5 PM, and try to have your dinner at least 2 hours before sleeping.

 

5. Mental Health Issues

Conditions like stress, anxiety, or depression can impact sleep quality. You may sleep for hours but still wake up tired due to mental fatigue.

Fix: Practice stress management through:

  • Journaling
     

  • Breathing exercises
     

  • Meditation
     

  • Seeking therapy if needed
     

 

6. Vitamin or Hormonal Imbalance

Low levels of Vitamin D, Vitamin B12, iron, or thyroid dysfunction can cause constant fatigue—even with good sleep.

Fix: A simple blood test can help detect deficiencies. You can book these tests via SecondMedic.com, powered by Thyrocare, with home sample collection.

Recommended tests:

  • Vitamin D Test
     

  • Vitamin B12
     

  • Thyroid Profile
     

  • CBC (Complete Blood Count)
     

 

7. Lack of Physical Activity

Not moving your body enough during the day can lead to low-quality sleep at night. Exercise helps burn excess energy and improves deep sleep.

Fix: Aim for at least 30 minutes of physical activity, like walking, yoga, or cycling daily.

 

Signs That You’re Not Getting Good Sleep

  • You hit the snooze button multiple times
     

  • You feel sleepy by mid-morning
     

  • You wake up with a heavy head or sore body
     

  • You need coffee immediately to function
     

  • You feel irritated, anxious, or unmotivated
     

These are signs your body is not truly rested.

 

Simple Tips for Better Sleep & Morning Energy

  1. Stick to a sleep schedule: Go to bed and wake up at the same time every day—even on weekends.
     

  2. Create a sleep-friendly space: Keep your bedroom cool, quiet, and dark.
     

  3. Limit naps: Daytime naps should be less than 30 minutes and before 3 PM.
     

  4. Stay hydrated—but not too close to bedtime: Drinking too much water late may wake you up to pee.
     

  5. Practice relaxation before bed: Try reading, light stretching, or herbal tea.
     

 

Conclusion

Feeling tired despite getting enough sleep can be frustrating. But remember, quality beats quantity when it comes to sleep. By making small changes in your routine, checking for hidden health issues, and improving your lifestyle, you can wake up feeling refreshed and ready to take on the day.

If you’ve been wondering why do you wake up tired even after 8 hours sleep, now you know where to start fixing it. Begin today with a better sleep routine—and better mornings will follow.

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