Vitamin D and its influence on your immune system
Vitamin D is hot. And that has actually been the case for years, but due to the recent pandemic, a lot of additional research is being done specifically into its effects on our immune system. And the effects of vitamin D on our resistance and immunity are not only interesting now, but actually every year in autumn and winter. What are the most recent insights? And do you have to take extra vitamin D or not? What is Wisdom?
First of all: what is Vitamin D?
Surprise! Vitamin D is not a vitamin! Vitamin D is actually a (pro)hormone that we produce ourselves under the influence of sunlight. This hormone is essential for the proper functioning of the immune system.
Vitamin D is a fat-soluble 'vitamin'. That means you have to take vitamin D with fat because otherwise your body can't absorb it. So if you take a supplement, take one that is in olive oil or take your capsule with some fat.
Incidentally, your body can only store fat-soluble vitamins to a limited extent. An excess amount taken leaves your body again (via urine or bile). You must therefore continue to take it regularly because you do not store it.
Vitamin D in mcg or IU units
Vitamin D is often listed in different units. It is expressed in mcg (microgram also written as µm) or in IU (International Units) or IU (International Units). The calculation to convert vitamin D from mcg to IU (or IU) is as follows: 2,5 mcg (or µm) = 100 IU. So 10 mcg is 400 IU.
The link between vitamin D and your immune system
This is where it gets really interesting. A group of researchers and doctors including Dr Gareth Davies (PhD Medical Physics, Imperial College, London) have formed an international alliance to encourage governments to increase the daily recommended intake of vitamin D to 4000 IU (100 mcg). For the Netherlands, this would mean a tenfold (or fivefold increase in the case of the elderly) of the current standard.
Their research shows that when vitamin D levels are high, the innate immune system is strong. This is our body's first line of defense. In many cases, our own innate immune system can already defeat an invader on its own.
From March to July, Dr Davies worked full-time as an independent coronavirus researcher and has continued his research part-time ever since. He states “for most people, the idea that a simple and widely available supplement can really help fight a pandemic is so ridiculous that they don't really take it seriously” and often dismisses it as a supplement industry sales pitch. (1)
But his research, which was pre-published in May (2) and combines methods from physics, data analysis and artificial intelligence, shows that a vitamin D deficiency leads to severe Covid illness due to the Sars-Cov-2 virus. A conclusion they draw from 1,6 million data points of deceased and recovered patients from 240 different global locations.
Mike Gleeson, professor of exercise biochemistry at Loughborough University, says a daily dose of 10 mcg (or 400 IU) would not be enough for someone who is deficient to get back to adequate levels. (3) He says: “It is cheap and safe and although it cannot prevent an infection, there is a good chance that it can reduce symptoms and speed up the recovery process. Nothing you consume can prevent contamination, but some things can influence the process.”
"If there's a danger of overdose, why don't we get it if we're in the sun too much?"
Worrying About a Vitamin D Overdose…
Why then is the current guideline not increased immediately? Governments are probably reluctant for fear that an overdose of vitamins would be harmful. Dr Davies is quite adamant about the dangers of vitamin D overdose. He really doesn't understand where the concern comes from, especially during a pandemic. He suspects it comes from ignorance. After all, it is a pro-hormone (and therefore not a vitamin) that we produce ourselves when we come into the sun. "If there's a danger of overdose, why don't we get it if we're in the sun too much?"
Who is now advised to take extra vitamin D?
- For anyone who doesn't go uncovered enough: if you spend less than 30 minutes a day between 11 and 15 p.m. outside in a strong (!) Sun. A powerful sun is one where you can see your own shadow. In autumn and winter, the sun is often not strong enough or simply absent in our regions. Please note that sunscreen also prevents absorption in the summer.
- For everyone (young and old) with tinted or dark skin: dark skin produces less vitamin D.
- Anyone over 50: This is especially true for women due to calcium absorption. Vitamin D is necessary to absorb calcium from food.
- Anyone over 70: As our skin ages, it is also less able to produce vitamin D.
How do you know if you have a vitamin D deficiency?
Do you want to test yourself whether you could benefit from a supplement? Then do here a self test. To be completely sure whether you currently have a deficiency or would benefit from a supplement, it is best to have a blood test done by your doctor. If you suspect that you have a (serious) deficiency, this is definitely recommended.
How Much Vitamin D Do You Need?
In recent years, the advice of the World Health Organization has already gone up. The maximum permitted level that can be safely sold in a supplement was also increased to 2016 mcg (75 IU) in 3000, and yet it appears that more than half of the women in our country over 50 years of age still have a deficiency. Almost 60% of GP visits are vitamin D deficient. (4)
The current guidelines are a supplement of 10 mcg (400 IU) except for the elderly over the age of 70, for which an advice of 20 mcg (800 IU) per day applies. (5)
And yet there are still so many people with a deficiency. Could this mean that the Dutch supplementation advice is still too low? Or that we simply don't get enough vitamin D because we don't take enough extra vitamin D?
How do you choose a good vitamin D supplement?
1. Desired Vitamin D dosage
Choose a supplement that contains at least 10 mcg (or 400 IU) of vitamin D. Also pay attention to the amount per capsule. Often there is a certain dosage on a package, but you only reach this if you take 2 or 3 capsules per day. This is not always convenient. The current advice may be insufficient to make up for a shortage. It is best to ask your doctor for personal advice on dosage.
2. Opt for a vitamin D in oil
Preferably choose vitamin D that is in a fat. This can be a liquid oil or a capsule made from olive oil. This is important because you need fat to absorb this vitamin in your body.
3. Vitamin D2 or Vitamin D3?
We can be brief about this: always choose vitamin D3, also known as cholecalciferol, because it is naturally produced in the body and is therefore much better absorbed.
Looking for a vitamin D capsule that combines all these properties? Then order the Live Puri vitamin D3 capsules here:
Are there any other supplements that help your immune system?
ISIN (international Society For Immunonutrition), a non-profit organization of scientists, clinicians and health professionals, issued a statement in March 2020 with some recommendations. About vitamin D, they say that anyone with a deficiency or recommendation should take 10 mcg (400 IU) to 100 mcg (4000 IU). In addition, they advise the elderly in particular to take vitamin E (134 mg to 800 mg), zinc (30 mg to 220 mg) and vitamin C (200 mg to 2 g) daily to promote their own immune system. (6)
Source reference:
- Nutritional ingredients Covid 19 scientists raise the vitamin D alarm
- Medrxiv Prepublication: https://www.medrxiv.org/content/10.1101/2020.05.01.20087965v3
- Nutritional ingredients UK gov urges vit D supplementation in fight against Covid 19
- IVG daily dose Maximum daily dose of vitamin D increased
- Nutrition center vitamin D
- ISIN statement Communicado Covid 19