Vitamin D is incredibly important for a strong immune system. First scientific evidence also shows that Vitamin D reduces Covid-19 infections, hospitalizations, and deaths (more on this later in this article).
Yet, vitamin D deficiency is one of the most common nutrient deficiencies in the world. It is, however, very easy to get your recommended daily dose. The best source of it is sunshine. Lots of foods (like fatty fish or egg yolks) are rich in Vitamin D.
In this article, I provide answers to how much vitamin D do you need, what’s the right amount of vitamin D, the best sources, the risk of deficiencies, how to supplement vitamin D, and its role in combating the coronavirus.
What Is Vitamin D and Why Do We Need It?
Vitamin D is a fat-soluble nutrient that is mainly responsible for the effective absorption of calcium, magnesium, and phosphate in our bodies.
The sun is our most effective source of vitamin D. Ultraviolet B (UVB) energy from the sun converts 7-Dehydrocholesterol (7-DHC, a type of cholesterol precursor that exists in our skin) to Vitamin D when exposed to sunlight. That’s why it is also often called “the sunshine vitamin.” The kidneys play an important role in this transformation to get to the final active vitamin D in our bloodstream. Low levels of vitamin D are often a consequence of chronic kidney disease.
The two main variants are vitamin D3 (also known as “cholecalciferol”) and vitamin D2 (“ergocalciferol”). D3 is about twice as effective as D2 in raising the levels of Vitamin D in our blood. D3 is the one produced by the sun and typically found more in animal-based food sources. D2 on the other hand tends to be available more from plant-based sources.
We need vitamin D because it’s important for strong bones, muscles, teeth, and general health such as proper immune system function.
Several studies also proved a positive effect on treating cancer. A 2020 meta-analysis study demonstrates “a clinically meaningful beneficial effect from vitamin D supplementation on survival outcomes” in patients with colorectal cancer. Recently, research shows the effectiveness of vitamin D to fight the coronavirus (more on this further down).
As a consequence, having sufficient vitamin D levels in our blood is vital for health, fitness, strength, endurance, and general happiness and performance in life. Vitamin D deficiency needs to be addressed for improved health. Especially in the case of obese and overweight people with deficiency, vitamin D supplementation aids weight loss and can even enhance the positive effects of calorie-restricted diets.
How Much Vitamin D Do You Need?
According to the Institute of Medicine (IOM), the recommended dietary allowance (RDA) of vitamin D for adults is 600 IU. IU stands for International Units and is used in pharmacology to compare volumes of different substances. In the case of vitamin D 600 IU corresponds to 15 micrograms. This should result in blood levels of 20 ng/ml, which should be the absolute minimum for strong bones. However, other authorities, like the U.S. National Academy of Medicine, argues that at least 30ng/ml are necessary for optimal bone health and to prevent diseases. In other words, the 600 IU are really on the very low end of recommended vitamin D intake.
To achieve the 30ng/ml levels of vitamin D, we should better aim for at least 1000 IU per day (25 micrograms). High doses of vitamin D of up to 4000 IU (100 micrograms) or even 5000 IU are absolutely safe. In fact, high blood levels of vitamin D seem to have no harmful effect. There is no upper limit. Only at some point, more vitamin D does not deliver any further benefits.
There are few reports that state that individuals with too much calcium in the blood, which could be a consequence of too high vitamin D intake, may suffer from constipation. This, however, is very rare as Dr. Mark Gordon confirms on the Joe Rogan Experience podcast #1589 (citing this study). Dr. Gordon takes 50000 IU of Vitamin D on Mondays and between 10000 and 20000 IU every other day.
What Are the Effects of Vitamin D Deficiencies?
Vitamin D deficiency is one of the most common nutrient deficiencies in the world. Estimates show that 50% of the world population is vitamin D insufficient. It especially occurs within infants, young women, older people, and people with darker skin. In the US, 82% of black people and 70% of Hispanics show some vitamin D deficiency. Diet plays a role too.
There was also a correlation found between being obese and vitamin D deficiency. And obviously not being exposed to direct sunshine (being indoors too much or using too much sunscreen) contributes to deficiency too. This is, however, a bit of a dilemma as we also do not want to risk skin cancer due to too much exposure to sun rays.
Typical symptoms are very weak and usually it takes a long time until they are noticed. These include:
- Getting sick a lot
- Slow healing of wounds
- Feeling tired or depressed a lot
- Feeling muscle, bone or lower back pain
- Losing hair
- Reduced bone mineral density
Above are some of the symptoms but what can these lead to?
Low levels of vitamin D can lead to various serious medical conditions including heart disease or celiac disease. Other clinical trials show that participants with vitamin D insufficiency have higher risk factors for hypertension (high blood pressure) and cardiovascular disease.
A lack of vitamin D can lead to weak bones or deformities such as rickets (a condition that affects bone development in children), and bone pain caused by a condition called osteomalacia in adults. In the worst case this can even lead to osteoporosis, which is the reduction of mass of the bones.
Other less “harmful” but at least very inconvenient consequences of vitamin D deficiency are related to the condition of our muscles and quality of sleep. Both are essential for athletes and athletic performance as they significantly influence our ability to balance daily strain and recovery.
Vitamin D deficiency is associated with sleep disturbances. The exact nature of sleep disturbance appears to depend on race and ethnicity. There are also anecdotal indications that if too much vitamin D is taken too late in the day it may interfere with melatonin production and hence sleep quality. This is very individual so I recommend to experiment with the right timing for yourself.
Similar to the effect of vitamin D on bone strength, lack of it also leads to muscle weakness and fatigue. Too low levels of active vitamin D (as described above) in our bloodstream leads to decreased muscle strength.
What Are the Best Vitamin D Sources?
In this section, I describe the main sources of vitamin D (sunshine, food, and supplements) and what you can do to raise your vitamin D levels.
Getting Vitamin D From the Sun
Exposure to sunlight is the best way to get vitamin D. That’s why it’s also called the “sunshine vitamin.” The amount of vitamin D you can get from the sun depends on various different factors, such as location, time of the year, age, gender, race, and ethnicity.
To get a better idea of what’s “enough” a study showed that 13 minutes of midday sun exposure three times per week while wearing T-shirt and shorts during summertime in the UK is sufficient to get the right levels of vitamin D among Caucasian adults.
People with darker skin have more melanin which acts as a natural sunscreen. Consequently, people with darker skin may have to spend more time in the sunshine. But then there is of course also always the risk of skin cancer. So you better balance this carefully.
The farther you live away from the equator the less intense the sun’s rays are. If you are really far away, like in the north of Europe (e.g. Scandinavia) you may not get any sun during the winter months. In that case, you need to find other sources of vitamin D like foods or supplements which I cover next.
Vitamin D Rich Foods
There is a lot of food that contains vitamin D like fatty fish (e.g., salmon, trout, mackerel, sardines, tuna), beef liver, some mushrooms, or egg yolks. Also, dairy products (like yogurt, or cheese), orange juice, and breakfast cereals are often fortified with vitamin D. The National Institutes of Health provide a good list of vitamin D rich foods including concentration.
But to put this into perspective, the concentration of vitamin D in most of these foods is very low. So you would need to eat a substantial amount of these every day to achieve the right level. One exception is fish liver oil where one tablespoon (15ml) contains 1360 IU (34 micrograms) of vitamin D. You can buy fish liver oil in its liquid form in bottles or as capsules.
If you cannot get enough sun and if you struggle to eat enough vitamin D through foods, the third option is to choose dietary supplements.
Vitamin D Supplements
The final low-risk way to achieve your daily vitamin D needs is to get corresponding medicines or nutritional supplements. There are lots of vitamin D supplements in the form of pills or capsules available on the market.
When you choose some, just make sure that it contains the right concentration for you, and most importantly that it is naturally sourced and does not include bovine gelatin, or any artificials or colorants. Also, ideally, the supplement combines vitamin D3 with monounsaturated fat (like coconut or olive oil) because with it your body can absorb it a lot more effectively.
I am personally a long time consumer of the vitamin D product by GoPrimal because it ticks all these boxes. Eventually, this led to our collaboration as part of which I am re-selling some of their products in my store.
How Can Vitamin D Supplementation Aid Fight the COVID-19 Pandemic?
We are in a pandemic. Covid hit us very surprisingly and really hard -- some countries and/or professions more than others. The whole world is confused, trying to understand and trying to find the best way out. We are all struggling. I am personally also very confused and, in fact, disappointed by the really bad quality of data, misleading reports and media communication and especially by a lot of the new rules and regulations to combat the pandemic. A lot of these are in my opinion counterproductive or often even plain stupid.
So, after my little rant, here is finally something that indeed can help us improve the situation and it’s easy and cheap:
Consume more vitamin D.
On December 7th, 2020, over 100 scientists, doctors, & leading authorities published an open letter to call for increased vitamin D consumption to combat COVID-19. In this letter they argue that “scientific evidence shows that higher vitamin D blood levels are associated with lower rates of SARS-CoV-2 infection.”
The evidence shown in this letter indicates that increased vitamin D intake would help reduce infections, hospitalizations, ICU admissions, and deaths. Furthermore, based on the evidence vitamin D’s influence on COVID-19 is not just correlation but very likely causal.
On another Joe Rogan Experience podcast (#1474) Dr. Rhonda Patrick who is an expert on vitamin D explains in detail that almost all corona deaths in the US were vitamin D deficient. She actually goes into an impressive level of depth about the role and importance of vitamin D in our body in general. Check out the recording to get all the details.
The body of research is growing and they are all conclusive: most severe Covid cases are substantially influenced by vitamin D deficiency.
A study from November 2020 showed that the fatality rate was 21% high in vitamin D deficient cases vs only 3.1% of death cases in vitamin D sufficient cases. The National Health Service (NHS) in the UK officially recommends to increase the vitamin D intake as it is “reducing the risk of coronavirus (COVID-19).”
Now with all the lock-downs, our governments want us to stay inside. As a consequence we get less exposure to sun and hence levels of vitamin D shrink further. To me this sounds counterproductive, or at least it means we really need to try and compensate vitamin D more via foods and dietary supplements. The recommendation in general (as I mentioned at the beginning of this article) and also specifically for the Covid situation is to consume between 4000 IU to 5000 IU daily.
The Benefits Are Overwhelming: Get Enough Vitamin D !
We need vitamin D because it’s important for strong bones, muscles, teeth, and general health such as proper immune system function. This is especially crucial during a time of pandemic.
According to the open letter of 100 scientists, doctors, & leading authorities (published on December 7th, 2020) scientific evidence indicates that increased vitamin D intake would help reduce Covid infections, hospitalizations, and deaths.
The main sources of vitamin D are natural sunlight, certain foods (especially fish liver oil but also fatty fish like salmon, trout, mackerel, sardines, tuna, beef liver, some mushrooms, or egg yolks, and dietary supplements.
The recommended daily dose is between 4000 IU 5000 IU of vitamin D. If you cannot get this amount via sun exposure or foods, consuming vitamin D supplements is a viable, convenient, cheap and safe option.
As part of my partnership with GoPrimal I am offering one of the highest quality vitamin D supplements on the market. GoPrimal’s vitamin D is sourced from sheep wool. It is blended with organic coconut oil to improve absorption. It is naturally sourced and absolutely clear of any artificials or colorants.
The fundamental idea of my 4 Legs Fitness concept is that you need to have a balanced approach to achieve superior health and fitness. Getting enough vitamin D is related to the right nutrition and is only one of the four areas that need to be considered. The others are strength, endurance and recovery.
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