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Vitamin D Is Critical To Your Immune Health & This Is Why

Written by: Nick Jack
Category: 2014
on 14 July 2020
Hits: 2523

One of the biggest threats to our health right now and something that is barely given a mention by the mainstream media is the damage to our immune system from a lack of vitamin D. If you are spending more time indoors than normal, and eating poor quality nutrition there is a very good chance you will have a vitamin D deficiency. For a long time experts believed vitamin D was primarily responsible for the regulation of calcium and bone health and the prevention of rickets. However, research over the past 20 years has shown that vitamin D influences much more than this and can have a huge impact on our immune cells to control and reduce inflammation. And if ever there was a time we needed our immune system to be running at its absolute best, it is right now!

How Common Is Vitamin D Deficiency?

According to results from the Australian Bureau of Statistics in 2011-2012 in winter, rates of Vitamin D deficiency were particularly high for those living in the south eastern states of Australia, like myself here in Melbourne Victoria, where 49% were found to be Vitamin D deficient in winter compared with only 16% and 13% respectively in summer.

When you consider these statistics were taken at a time when we were not in lock-down and people were not studying and working from home all the time, it is frightening to think what they might be like now!

The time we spent outdoors in the sunlight travelling to and from work or school would have given our bodies a much needed boost in vitamin D. It is fair to say these statistics are highly likely to be much worse now, in particular with older adults, which is a real concern considering how important it is to their immune system.

People working in office jobs, warehouses, and even hospitals are also at higher risk of being Vitamin D deficient.

Statistics form the Australian Bureau of Statistics conclude that vitamin D levels were also associated with the type of work people do, with those employed in occupations based mostly inside, such as sales workers (28%) and professionals (26%) being more likely to have a vitamin D deficiency than those working in jobs based mostly outside, such as tradespeople and drivers (18%).

While the media loves to scare the community with the amount of Coronavirus cases and that there is nothing you can do until a vaccine comes, we must put our efforts into doing all the little things we can do to ensure our bodies are as healthy as they can be. It is almost like they are saying “wait until you get sick and then we can use drugs to make you better”. Instead of giving you information and useful advice about the things you can do to prevent getting sick.

Eating quality nutrition and exercising are not a luxury, they are essential to your health. The older you are, or the more vulnerable you are, the more important this becomes. Make no mistake about it, ensuring you have adequate levels of Vitamin D possibly is arguably the greatest thing you can do to for providing your body with the tools it needs to fight off infections.

Why Is Vitamin D So Important?

I cannot say how many times I have discussed the value of vitamin D in articles I have published relating to illness and disease. In recent months due to the community concern relating to COVID-19 I have looked very closely at the immune system, lung capacity, diabetes, and heart health, and every time it has featured as an important factor in both prevention and treatment of these health problems.

For me personally, I am very aware of the damage lack of Vitamin D can cause, for I suffer from Psoriasis and my skin is noticeably worse in the winter months when there is a lack of sunlight. I have always made an effort to spend time outdoors in the sun every day and eat various foods that are loaded with the necessary vitamins and minerals I need to help keep my skin under control.

But there is so many more important roles it plays other than keeping my skin under control, and I really want to drive home how important this is considering how vulnerable so many people are right now with the world in the middle of a pandemic.

There are only 30,000 genes in your body and vitamin D has been shown to influence over 2,000 of them and is one of the primary reasons it influences so many diseases. Interestingly vitamin D really isn’t a vitamin at all, but a potent neuro-regulatory steroidal hormone.

Studies also reveal that low vitamin D levels in the body are associated with:

Despite the importance of vitamin D, it’s estimated that anywhere from 30% to 80% of the population is vitamin D deficient! This is quite alarming considering how important it is to our health of our immune system which is under threat right now. If you are thinking all you need to do is pop some supplements and you will be fine, think again. Unfortunately it is not quite as easy as that as we do not all absorb Vitamin D as efficiently.

Vitamin D levels can also be affected by age and body fat levels. As we age, our ability to make vitamin D is reduced by 75%. Furthermore, vitamin D can get trapped in body fat, leading to a 55% reduction in blood levels for those who are over-fat.

This information is extremely important to understand in our current times as it also suggests to you why these populations are more at risk of serious health problems. More on this later.

Sunlight Is the Best Form Of Vitamin D


Vitamin D isn’t really a “true” vitamin, as we don’t need food to attain it. Natural sunlight allows our body to create vitamin D and even destroys excessive amounts. The infograph from Precision Nutrition above gives a great visual of how we obtain vitamin D.

What about trying to get your vitamin D through office or car windows?

Unfortunately this does not work too well as glass blocks virtually all UVB, preventing vitamin D from being made.

And sunscreen has a similar result. While it may help prevent cancer melanomas, applying sunscreen with a block level of 15 will decrease the amount of vitamin D made in the body by about 99%. This is a bit like solving one problem just to create a new one.

How much sunlight do you need?

Sun exposure (without sunscreen) of about 10 to 15 minutes a day, with at least 40 percent of your skin exposed, is a general guide of how much you need, although people with dark skin will need to stay out significantly longer.

Spending 20 minutes riding your bike outside in the summer sun produces 100 times more vitamin D than the recommended daily amount. And once you reach the maximum level any excess is deactivated automatically by the body so you cannot overdose on it.

Vitamin D Deficiency & COVID-19

If you are like me you are probably sick and tired of reading all about COVID-19, but having said that I came across some very interesting reports recently that I thought you would be interested to read. I read lots of detailed reports and books and when you dig deep you find out some amazing stuff. One of the more interesting books I have read the past few weeks is called "The elegant defense and the extraordinary new science of the immune system" by Matt Richtel. It has some fascinating insights into how the immune system works and just how much we still do not understand of this remarkable part of the human body.

A recent analysis by the University of Chicago of over 4000 patients was designed to examine whether vitamin D deficiency and treatment are associated with testing positive for COVID-19. They found that vitamin D deficiency that was not sufficiently treated was associated with an increased risk for COVID-19 infection.

Another study involving 212 patients in Southeast Asia shows that of those with a COVID-19 case that was critical or severe, only 4% had normal levels, while 96% of those with mild COVID-19 had normal vitamin D levels. See the graph below.

The next graph jumped right off the page when I first saw it and this is a retrospective study from of 780 cases with laboratory-confirmed infection of SARS-CoV-2 in Indonesia. When controlling for age, sex, and comorbidity, they found that vitamin D status was strongly associated with COVID-19 mortality outcome of cases. A summary of their findings are in the impressive graph below that demonstrates a radical reduction in the death rate from COVID-19 as the vitamin D level increase to over 30 ng/ml.

You can access more of these graphs and the complete report with all the science and medical journals supporting the claims by clicking here.

What Foods Contain Vitamin D?

Vitamin D is extremely rare in foods. It’s found in fish, cod liver oil, mushrooms, liver and eggs – but usually not in substantial amounts (except in cod liver oil). I used cod liver oil for a long time when trying to get on top of my psoriasis and it does work wonders. One tablespoon contains about 1,300 IUs of vitamin D, which is more than twice the recommended dietary allowance of 600 IUs per day.

In the book Nutrition and Physical Degeneration by Weston A Price the use of Cod Liver Oil was a common practice in the 1930's and 40's to rid many people, in particular children of rickets and various bone related disease. I highly encourage you to take a look this book if you want to really understand nutrition.

Fatty fish can be a good source of vitamin D. Common options include salmon, trout, mackerel, tuna, and eel. A typical size salmon fillet contains about 450 international units (IUs) of vitamin D although farmed varieties of fish contain very little vitamin D compared to the wild varieties.

Eggs are another great source to get vitamin D. Since the vitamin D in an egg comes from its yolk, it's important to use the whole egg and not just the whites. One yolk will give you about 40 IUs, but don't try to get your daily vitamin D just from eggs as you run the risk of eating too many and developing an allergy.

You can read more about the benefits of eggs and get 5 great recipes by clicking here.

While there are some foods that help boost your levels, getting enough vitamin D from whole foods alone is virtually impossible; it truly is the sunlight vitamin.

What about Using Supplements?

Many studies show that vitamin D supplementation cannot reproduce sunlight’s health benefits. Moreover, excessive vitamin D supplementation can aggravate systemic sulfate deficiency, which will drive calcium build up in the arteries. Which is obviously not a good thing. If you take more than 10,000 IU per day of vitamin D orally for more than 6 months, you are definitely at risk of becoming vitamin D intoxicated.

It has been found that magnesium supplementation is recommended when taking vitamin D supplements. Magnesium helps activate vitamin D. All the enzymes that metabolize vitamin D seem to require magnesium, which acts as a cofactor in the enzymatic reactions in the liver and kidneys. The dose of magnesium should be in the range of 250–500 mg/d, along with twice that dose of calcium.

A recent review found in the detailed report I shared earlier that as many as 50% of Americans taking vitamin D supplements may not receive significant benefits. This happens when the vitamin D they take gets stored in its inactive form because they have insufficient magnesium levels. Magnesium supplementation was shown to markedly reduce the resistance to vitamin D treatment.

If you are thinking of taking supplements I would advise you to speak to your Doctor or a qualified nutritionist who can help guide you on the right amounts so you do not intoxicate your body with too much.

I always have found that the person who relies on supplements and tries to get their vitamins from a pill is trying to take shortcuts with their health. While sometimes it is unavoidable there are many people who see this as the easy way instead of cleaning up their nutrition and lifestyle habits.

If you eat right and exercise, and in this case spend time out in the sunlight you will not need a pill or tablet.

Just remember, we cannot become vitamin D intoxicated from excessive sunlight.

What Concerns Me Right Now

Now that you know all this important information about Vitamin D are you as gobsmacked as I am that nobody is talking about this more. Why is the media not telling us the things we need to do to strengthen our immune system as much as possible?

Being put into lock-down may be necessary to prevent the spread but when we also neglect the importance of good nutrition and in this case sunlight from Vitamin D we are now weakening the immune system. And remember the people with a strong immune system will fight off the infection more easily. It has nothing to do with good luck.

If more people on the borderline of being a vulnerable health were able to improve their immune system it would be fair to say there may be much lower death rates.


When people were panic buying at the supermarket they were not panic buying good nutritious foods, it was the processed stuff devoid of any nutritional value that had long use by dates they wanted. This tells me that people were eating worse foods, exercising less, and many not getting outside as much as they were before.

We know this is true for the statistics of people gaining weight during COVID-19 has been well documented. A poll in the US found almost one-quarter of the men said they'd gained weight “due to COVID restrictions.” A separate poll of 900 international readers found more than half of men and about a third of women reporting weight gain!

You can see the full details on this in the article we shared recently How to go from Zero to Hero with your fitness

Also when you observe who are the highest of risk with COVID-19 due to a compromised immune system we think of people in aged care and people in hospitals. What is one thing both of these places have in common?

Lack of sunlight!

The very thing that makes us more vulnerable to infections is exactly what we are doing when we lock ourselves up inside. Now I am not saying to disobey the government regulations and ignore the lock-downs, all I am trying to say is that we need to be aware of getting outside to exercise and eating well.

I would like to say that at least the nutrition may be of the highest standard in a hospital but often that is not the case. Nutritional requirements for seniors are much different and we need to appreciate the value of getting this right and not rely on a pill or tablet to do the work.

Last year my mum was in hospital for 3 weeks due to a hip fracture. She was then moved to a rehab facility for a further 6 weeks. During this 9 week time frame she never went out into the sunlight unless I came in and sneaked her outside. (I was told I was not allowed to leave the grounds but I did anyway.) Over the course of 9 weeks she would have been lucky to see a total of 3 hours of sunlight! Well below the daily minimum we need to sustain a healthy immune system.

She already has a weakened heart, has chronic asthma, and is on a massive list of medications with all types of side effects. The food she was given was okay but not of the best quality and definitely not loaded with the stuff she really needed. I am not trying to criticise the medical community as they are doing the best they can, but I do have issues with the way the medical community portray the benefit of nutrition and exercise for preventing diseases.

For more information of how to boost your immune system make sure you check out article - 8 Ways to Boost Your Immune System

Do You Need More Help?

Make sure you get a copy of our detailed report below that features everything you need to know about improving immune health, and more specifically heart and lung health. I created this report in September 2020 to include ALL of the specific exercises and foods to eat for treating and preventing various heart and lung conditions. Click here to download your instant PDF copy.


I hope this article has given you a greater understanding of the vital role that Vitamin D plays with relation to the health of our immune system.  The sicker you are and the older you are, the more important spending time outdoors and eating quality food is to your health. I find it astounding to see this message is not being spread by the media who just want to scare us and incite panic to sell more newspapers and increase their TV ratings. While there are many things we cannot control with regards to COVID-19, there are many simple things we do have control over and we must dedicate the time to getting it done.

If you enjoyed this article, live in Melbourne, and would like to organise a Free Consultation to discuss how we can help you improve your health and immune system click the image below to fill in a contact form and I will be in touch within 24 hours to schedule a time.

About The Author

Nick Jack is owner of No Regrets Personal Training and has over 15 years’ experience as a qualified Personal Trainer, Level 2 Rehabilitation trainer, CHEK practitioner, and Level 2 Sports conditioning Coach. Based in Melbourne Australia he specialises in providing solutions to injury and health problems for people of all ages using the latest methods of assessing movement and corrective exercise.


  • Precision Nutrition
  • Weston A Price Foundation
  • Mercola
  • The elegant defense and the extraordinary new science of the immune system - by Matt Richtel
  • Movement - By Gray Cook
  • Corrective Exercise Solutions - by Evan Osar
  • How To Eat, Move & Be Healthy - by Paul Chek