Vitamin D may just well be the most important nutrient ever known to humankind.
I know that’s a bold statement, but vitamin D has been a keen interest of mine for decades and a topic for books and papers I have published.
The last few years have revealed dramatic benefits attributed to vitamin D. Researchers have discovered how valuable it is for many aspects of health – and how common widespread vitamin D deficiencies truly are.
It’s never been a higher priority than it is today to have sufficient vitamin D stores to support your immune function, respiratory, bone and cellular health, and so much more.
A fat-soluble steroid hormone, vitamin D penetrates nearly every cell in your body and passes into the cell’s nucleus to control the expression of as many as 3,000 genes.
This means vitamin D actually modifies how the cells in your body behave and function.
Vitamin D receptors are found in many different tissues and cells in your body, including your immune cells – proof of how important vitamin D is to your immune function.*
By influencing your two arms of immune function – your innate, or frontline protection, and adaptive immune responses – vitamin D is key to optimal immune health.*
Are You Vitamin D Deficient?
As more people test their serum levels, it’s becoming apparent that most people aren’t getting enough vitamin D.
Worse, many individuals have dangerously low levels – far lower than what’s needed to support physical and mental health.
Are you deficient? You may be low in vitamin D if you...
Spend minimal time outdoors and wear sunscreen.
Direct sunlight exposure is, by far, the best way to get your vitamin D, as your skin produces vitamin D when exposed to the sun’s ultraviolet rays.
However, few people get enough of the right kind of exposure to receive adequate supplies of the vitamin. And if you wear sunscreen, it filters out the UVB rays that produce vitamin D in your skin. Plus, showering right after sun exposure can reduce your body’s production of the vitamin.
Are over the age of 50.
As you age, your skin loses the ability to generate vitamin D and your kidneys become less efficient at converting vitamin D to its active form.
Plus, older individuals tend to spend more time indoors so they get less sun exposure.
Have darker skin.
People with darker skin tones have higher melatonin levels, which block UVB radiation and limits the body’s ability to produce vitamin D.
Individuals who are overweight often have considerably higher needs for vitamin D because the nutrient can accumulate and become “trapped” in body fat, or adipose tissue, preventing it from getting to the blood.
Increasing your activity level may help release bound vitamin D from adipose tissue.
Have a gastrointestinal issue that affects fat absorption.
Vitamin D is a fat-soluble vitamin and is absorbed with dietary fat. If you severely restrict fat in your diet or have an issue with absorbing fat, you are more likely to have low vitamin D levels.
Why Your Location Influences Your Risk for Deficiency
While the best way to maintain healthy levels of vitamin D is through sun exposure, where you call ‘home’ may make this a challenge.
During the winter months, in non-tropical or subtropical locations, the sun’s rays have to penetrate extra layers of the atmosphere that essentially filter out most, if not all, of the ultraviolet (UVB) rays.
Yet, winter isn’t the only time of year people may not be able to produce enough vitamin D naturally and become at risk for deficiency...
A minimum of 10 to 15 minutes of regular, direct sun exposure on sufficient exposed areas of your body at the right time of day is needed for absorbing enough UVB rays to produce vitamin D.
Therefore, the risk is high throughout the year, with research suggesting that up to 85% of people may be vitamin D deficient.
The chart below shows how much UVB rays from direct sun exposure you can expect to receive throughout the year in the U.S. As you can see, in the months of January and February, the sun is simply not close enough anywhere in the U.S. for vitamin D synthesis to occur.
In some areas, there are many other months, too, where UVB rays will be hard to obtain, leaving you at risk for vitamin D deficiency. It can even be challenging during summer months in some regions to get enough natural vitamin D from the sun.
Note: If you live outside of the U.S., consult the Sun or Moon Altitude table to determine how far the sun is from your location at any given time.
11 Clues You May Be Deficient in Vitamin D
In recent years, researchers have discovered that there are physical and mental signs of deficiency or sub-par levels of vitamin D. How many of these ring true for you?
Studies suggest that nerves have vitamin D receptors. Low levels of vitamin D may contribute to deep muscle hypersensitivity.*
Because vitamin D regulates your body’s levels of calcium for bone health, low levels of vitamin D could have adverse effects on bone health.*
In one study of 174 patients with fatigue (but stable health), 77% were found to be deficient in vitamin D. Once serum vitamin D levels returned to normal, feelings of fatigue improved significantly.*
Reduced muscle performance
Higher serum levels of vitamin D are associated with reduced injury rates and improved sports performance. Vitamin D plays key roles in muscle development, strength and performance.*
Mood and cognitive function
Vitamin D helps buffer higher calcium levels in the brain, just like it does in your bones, making it essential for brain and neuron health, a healthy mood and proper cognitive function.*
Cardiovascular and blood pressure concerns
Found to have a significant effect on the endothelial cells that line your cardiovascular system, vitamin D3 supports healthy circulation and blood pressure levels already in the normal range.*
Research has linked low levels of vitamin D with poor quality sleep and a greater risk of sleep challenges.
Abnormal sweating (especially on your head) or a change in how you sweat may suggest low levels of vitamin D.
Vitamin D plays a key role in your hair cycle, and vitamin D receptors appear to be important for hair growth.
Vitamin D plays a key role in your hair cycle, and vitamin D receptors appear to be important for hair growth.
Studies show an association between excess amounts of body fat (especially in the abdomen) and low blood levels of vitamin D. How the two factors are related isn’t yet clear, but researchers believe much higher levels of vitamin D are needed to achieve the same serum concentration compare to lean subjects.*
As you can see, vitamin D (specifically the vitamin D3 form) has a far-reaching and significant impact throughout your body, affecting just about every function in your body.
Let’s make sure you are getting the right amount...
Determining Your Exact Dose of Vitamin D3
The only way to know for sure if you are low in vitamin D is to check your blood serum levels regularly.
We offer convenient test kits in the Mercola Market to help you check your levels of vitamin D, along with other important vitamins and minerals, such as magnesium, in the privacy of your home.
If your levels are low, I recommend either dramatically increasing your sun exposure time (if feasible) or taking a vitamin D3 supplement.
How much supplemental vitamin D should you take?
GrassrootsHealth now recommends a blood serum level of 50 ng/mL or higher for optimal immune and cellular health. While they used to recommend 40-60 ng/mL as the ideal level, the most recent data supports a minimum of 50 ng/mL for immune health.
My vitamin D3 recommendations are even higher. Based on the latest studies, I believe your blood level should be closer to 60 ng/mL to 80 ng/mL.
Most people have significantly lower blood levels than this, so what should you do if your levels are below this range?
Table 1 below by GrassrootsHealth provides a guide for correcting low levels of vitamin D using an upfront loading dose for fast results.
Using your results from a current vitamin D test, find your 25(OH)D serum levels in the left-hand column. Follow it across the chart for the recommended dosing and number of weeks to raise your levels to above 50 ng/ml.
Table 1. Guidance on upfront loading dose regimens to replenish Vitamin D stores in the body
|8 - 10
|1.5 - 1.8
|11 - 15
|8 - 10
|1.0 - 1.2
|16 - 20
|6 - 8
|0.8 - 1.0
|21 - 30
|4 - 6
|0.5 - 0.7
|31 - 40
|2 - 4
|0.3 - 0.5
|41 - 50
|2 - 4
|0.2 - 0.3
If you don’t yet have your vitamin D test results or know your baseline serum level of vitamin D, there’s an alternative – yet less precise – way to know how much supplemental vitamin D to take.
Table 2 uses a method based on your body mass index (BMI), which is a measure of the amount of body fat in your body based on height and weight.
As you can see below, overweight individuals require substantially greater amounts of supplemental vitamin D than normal-weight individuals to reach and maintain a serum level of 50 ng/mL.
Table 2. Vitamin D dosing in the absence of a baseline Vitamin D level
|BMI ≤ 19 (under-weight)
|40 - 70
|≃ 2,000 - 4,000
|BMI 20 - 29 (non-obese person)
|70 - 100
|≃ 5,000 - 7,000
|BMI 30 - 39 (obese person)
|100 - 150
|≃ 9,000 - 15,000
|BMI ≥ 40 (morbidly obese person)
|150 - 200
|≃ 16,000 - 30,000
When correcting low levels, I recommend testing again in three to six months to make sure you are getting the right amount of vitamin D.
How to Get the Preferred Form of Vitamin D You Need
Before you start loading up on milk, cheese, salmon and other food sources, know this about the vitamin D in food:
The majority of foods, including milk, don’t contain enough vitamin D3 to result in optimum levels in your blood.
Some foods, such as milk, are “fortified with vitamin D3,” but are not natural sources. The levels of vitamin D added to milk are far too low to meet your daily needs.
Because vitamin D is so lacking in food, for most people, the best way to get enough vitamin D in the absence of sun exposure is to take a supplement.
However, here’s what you need to know about vitamin D supplements...
There are two different types of vitamin D used in supplements – vitamin D2 (“ergocalciferol” or pre-vitamin D) and vitamin D3 (“cholecalciferol”).
Both naturally occurring forms are produced in the presence of the sun’s UVB rays, but D2 is produced in plants and fungi, and D3 is produced in animals, including humans.
While both forms are somewhat similar in structure and share some beneficial effects, studies show they differ considerably. One study found that D3 has a positive effect on mood, whereas D2 does not.
Another recently published study with 335 women ages 20 to 64 looked at how the two forms act in your bloodstream and affect immune health. Comparing the two forms, the study found that vitamin D3:
- More effectively increased vitamin D levels in the bloodstream.*
- Supported a stronger immune response to threats.*
What’s more, this study found that vitamin D2 may actually have a detrimental effect.
Supplemental vitamin D2 may make you more vitamin D3 deficient. The group taking a D2 supplement had less D3 in their blood than the placebo (non-supplementing) group.
This finding supports earlier research showing how a vitamin D2 supplement can displace the normal, native D3 in your body, affecting some vitally important pathways.
The ‘5-Second Solution’ for Safeguarding Your Health
We’ve come up with a way for you to get the exact amount of vitamin D3 you need in a pleasant-tasting, no-capsule form.
Our Vitamin D3 Sunshine Mist® spray provides what we consider to be the most biologically active vitamin D3 supplement.
Supplying 5,000 IU of Vitamin D3 in each convenient, metered dose, our Vitamin D3 Sunshine Mist spray:
- Comes in a delicious natural orange flavor without any artificial flavors or colors.
- Does not contain any sugar, wheat, yeast, soy, gluten, eggs, salt or dairy.
- Uses a non-aerosol, non-drip dispensing container to deliver its nutrients in a form your body can put to use immediately.*
With no pills or capsules to swallow, when you spray Vitamin D3 Sunshine Mist into your mouth, the fine mist promotes rapid absorption of the nutrients into your bloodstream, tissues and cells.*
Because of the absorption challenges some people experience with vitamin D, a spray may be the preferred way to take it in its oil form.
Convenient to carry and use, our pre-metered spray container easily fits in your purse, pocket or backpack.