Vitamin D and COVID-19 infection - Evidence Review

Vitamin D and COVID-19 - Can It Lower Your
Risk?
Dr Vivek Baliga B

Vitamin D and COVID-19 - Can It Lower Your Risk?
The COVID-19 crisis is giving many sleepless nights. Many are looking for
ways to build up their immunity in order to lower their chances of getting
infected. Reports suggest a relationship between vitamin D and COVID
infection – one where vitamin D protects you against it.
I thought I would explore the existing literature today.
The COVID-19 Crisis
You will be aware that the COVID-19 infection, also called SARS CoV-2, is a
viral infection that is sweeping our planet and affecting many. It acts
through numerous mechanisms, leading to fever, cough, loss of taste and
smell, body pain, and in some cases diarrhoea and vomiting.

The only way to prevent this infection effectively is to practice social
distancing, wash your hands regularly with soap and water at home, use a
sanitizer with at least 70% alcohol when you are out of the house, and of
course, to wear a tight- tting mask.
Staying healthy is also essential to build up immunity against the
coronavirus infection. Regular exercise, a healthy balanced diet with plenty
of fruits and veggies, and a good night’s sleep is of paramount importance.
A good intake of vitamins and minerals is needed to keep our immune
system at full guard. Vitamin D has a role to play in this.
The Role Of Vitamin D In Immunity
Vitamin D has been primarily recognised as a vitamin essential for bone
health. Vitamin D and calcium work as a pair in strengthening our bones,
keeping them healthy and preventing fractures.
Interestingly, vitamin D also helps boost your immunity. This is in fact old
news, with vitamin D supplements (in cod liver oil) being
.
previously used to
treat lung tuberculosis
Our immune system consists of various types of cells. These include
monocytes, dendritic cells, B cells, T cells, and macrophages. Each of these
have a role to play when ghting viral infections, including COVID-19.
Even those taking precautions are getting affected, mostly because some
people around them are not.

This burst of cytokine release is called . Vitamin D can lower
this signi cantly.
cytokine storm
There are many other mechanisms through which vitamin D can boost
immunity. I will not be discussing them here as it is out of the scope of this
article.
Vitamin D versus Common Cold
The common cold is probably the most ‘common’ infection us humans
suffer from. Visits to the doctors are mostly due to runny nose and chest
congestion, especially in the rainy and cold winter months.
On the surface of these cells are tiny receptors called Vitamin D receptors, or
VDR. When the immune cells move to sites within the body where there is
in ammation, the vitamin D binds to the VDR, forming a complex.
This complex moves into the nucleus of the immune cell, where it modi es
the genes and produces antimicrobial compounds like defensin and
cathelicidin.
This phenomenon leads to lower production of harmful products called
cytokines. Cytokines are generally released in large quantities in COVID-19
infection, overwhelming the body and leading to rapid deterioration of
patients.

The bene ts have been seen in .both adults and children
In children, a combination of regular vaccinations and vitamin D
supplementation has been found to boost immunity against respiratory
tract infections. It also reduces the chances of needing antibiotics.
However, the bene t may not be seen in all.
For example, in a who
were taking steroid inhalers, addition of vitamin D supplements did not help
reduce cold or severity of it.
study looking at adults with mild to moderate asthma
The maximum bene t of vitamin D supplementation to boost immunity
against chest infections was seen in .those who were de cient
In general, combining vitamin D with vitamin C supplements can lower the
duration and severity of the common cold.
Vitamin D has also been shown to have a protective effect against viruses
such as the and as well.rotavirus HIV
Studies have found that a dose of 400 IU per day of vitamin D can build up
immunity against chest infections. Doses up to 2000 IU per day have also
been advised.

There is a that describes vitamin D supplementation as
an effective way to prevent chest infections.
plethora of evidence
So is there a connection between vitamin D levels and COVID-19 infection?
The levels of vitamin D that we have in our body reduces as we get older.
Unfortunately, our chances of catching the COVID-19 infection increases as
we get older too.

In a very recent study, low vitamin D levels were found to worsen conditions
(high blood pressure, heart disease etc) that would
and an ability to ght COVID infection.
indirectly lead to lowered
immunity
In other words, if you have low vitamin D levels,
could not only lower your chances of contracting COVID-19; it
could lower the severity of the infection if you did. There appears to be a
bene t of as well.
topping it up with
supplements
vitamin D supplements for children
As is the case always, there are proponents of the opposite. The National
Institute of Clinical Excellence (NICE) in the UK has
, and categorically states that there is no strong evidence
supporting a role of vitamin D supplementation in COVID-19.
extensively reviewed the
available evidence
What Dose Of Vitamin D Is Needed To Boost
Immunity?
In a rather , it was found that people who lived in countries
below 35 degrees northern latitude had a lesser chance of dying from
COVID-19. This was because those that are above the 35 degree latitude had
lesser exposure to sunlight, and hence more likely to be vitamin D de cient.
interesting study
In another study looking at COVID-19 patients admitted to an ICU,
researchers found that lower vitamin D levels ampli ed the symptoms of
COVID-19.

I generally recommend 2000 IU daily to keep levels at an appropriate value.
Higher doses can cause abdominal pain, constipation, increased thirst,
vomiting and high calcium levels.
The recommended daily dose for vitamin D is around 600 IU to 800 IU a day.
However, those that are de cient will require between 2000 IU to 4000 IU
daily.
If you have ever checked your vitamin D level in a clinical laboratory, you will
nd that levels below 30 ng/ml are described as de cient.
Studies suggest that keeping your vitamin D level around 50 ng/ml is ideal
to protect you against viral infections.

Bottom Line and Closing Remarks
Are Vitamin D Supplements Safe?
There appears to be a connection between vitamin D and COVID infection.
There also appears to be a role in vitamin D supplements lowering your
chance of developing COVID infection as well.
Generally yes. But you must bear in mind that vitamin D is a ‘fat soluble’
vitamin. This means that any excess ingested can accumulate in the body.
However, there is still data needed.
This can be harmful.
As such, 2000 IU a day is a safe dose to take. If you are de cient, you may
need a higher dose. Talk to your doctor about what is right for you.
Should I Take Vitamin D Supplements To
Prevent COVID Infection?
As vitamin D is only obtained through sunlight exposure, it is likely that you
will .need a supplement right now
We are all locked up in our houses, and even sitting out on your terrace
every morning may not give you the dose you need.
There are plenty of available in
the market. If you are confused about what to take, speak to your doctor.
over-the-counter supplements of vitamin D

I personally feel that more randomized trials that look particularly at the
relationship between vitamin D levels and COVID infection are needed. This
will obviously take time.
When you get a chance, check your vitamin D levels in a lab and ask your
doctor if you need supplements. In addition to possibly offering protection
against the COVID-19 infection, it will most certainly keep your bones and
muscles healthy.

Vitamin D and COVID-19 infection - Evidence Review

Recommended

Recommended

More Related Content

More from Dr Vivek Baliga

More from Dr Vivek Baliga (20)

Recently uploaded

Recently uploaded (20)

Vitamin D and COVID-19 infection - Evidence Review