By Dr. Mercola
Nine out of ten Americans may be deficient in Vitamin D and not even know it. Are you getting enough of this vital nutrient? If you are taking a supplement, is it a form your body can easily absorb for optimal benefits?
There are over 34,000 scientific investigations to date on how vitamin D works in your body, yet it continues to be ignored by large segments of the population and even many doctors.
Vitamin D deficiency is often one of the last things a doctor suspects when a patient complains of less-than-perfect health.
If you use optimal levels of vitamin D to gauge a deficiency, you find that approximately 90 percent of people need higher vitamin D levels.
Unfortunately, many people are deficient because they aren’t able to obtain enough vitamin D through direct sunlight and their diet alone, and they aren’t taking a high-quality supplement.
Of those that are supplementing with vitamin D, they are most likely using a form that is not absorbed well by their body, and they aren’t receiving optimal benefits.
Before we take a look at your personal risk level of becoming deficient in vitamin D and I tell you my recommendation to maintain optimal levels, let’s first review why vitamin D is so important to your overall health…
Why Vitamin D Is ESSENTIAL for Your Entire Body
Once thought of as playing a primary role in osteoporosis and osteomalacia, researchers now realize that vitamin D affects virtually every cell and tissue in your body. And it affects numerous vitamin D receptors located throughout your body and nearly 3,000 genes.
Vitamin D is produced when the sun strikes your skin under the right conditions
Your cells need the active form of vitamin D to unlock the genetic blueprints stored inside the cell. Without these crucial blueprints, these aspects of your health could potentially be at risk:
- Maintenance of overall health*
- Cellular growth and development*
- Bone strength and health*
- Blood sugar health*
- Digestion and absorption of nutrients*
- Blood pressure health*
- Heart health*
- Vascular system health*
- Immune function*
- Joint health*
- Mood and overall feelings of well-being*
- Neurological and cognitive health*
- Muscular function*
- Skin health*
- Pancreatic function and health*
- Healthy aging process*
- Sleep patterns*
- Hearing and vision*
- Reproductive health*
- Newborn health*
- Athletic performance*
- Respiratory function and health*
- Carbohydrate and fat metabolism*
- Metabolic rate*
- Weight management*
- Hair and hair follicles*
I realize this is a long list. Yet, as research continues on vitamin D, you can expect to see it grow even longer!
What’s YOUR Risk Level for This Hidden Deficiency?
The only way to know for sure if you are vitamin D deficient is to regularly test your blood levels.
Because of vitamin D’s wide-reaching effects in your body, always check to see if you are deficient in this crucial nutrient when addressing any health concern, especially those listed above.
Certain groups of people may be at an increased risk for vitamin D deficiency, as well as individuals with some specific conditions. If any of the following apply to you, please get your vitamin D levels checked sooner than later.
- It’s winter and you don’t live in the tropics or subtropics.
There simply isn’t enough, or even any UVB radiation that reaches the ground in the winter if you are not in the tropics or subtropics, and exposure to UVB radiation is how your body produces most of the vitamin D it requires naturally.
- You have darker skin.
Those with darker skin may need as much as 10 times more sun exposure to produce the same amount of vitamin D as a person with pale skin.
- You’re 50 or older.
As you get older, your skin produces less vitamin D when exposed to the sun.
- You spend a lot of time indoors.
If you avoid the sun or just aren’t able to get outdoors regularly, your levels of vitamin D are likely to be lower.
- You’re overweight or obese (or have a higher muscle mass).
Vitamin D is a fat-soluble, hormone-like vitamin, so body fat can act like a sponge. A heavier person with more body fat or even those with more muscle mass may require a higher dose than a slimmer person.
- You have gut issues.
If you have a gastrointestinal condition that affects your ability to absorb fat you may have lower absorption of vitamin D.
- You’re achy or tired, or both.
The classic signs of a certain type of vitamin D deficiency can mimic conditions characterized by fatigue and achy bones.
- You sometimes feel “blue.”
Serotonin, the brain hormone associated with mood elevation, rises with exposure to bright light and falls with decreased sun exposure.
- You’re pregnant.
Pregnant women require higher amounts of vitamin D for their own pregnancy and delivery as well as the optimal health of their babies.
- You notice unusual head sweating.
Surprisingly, one of the first signs of a vitamin D deficiency is a sweaty head.
Please note, I offer vitamin D testing kits in my online store as a convenience for those who don’t have easy access to testing.
A Daily Dose of Sunshine Fixes Everything, Right? Not So Fast…
Your skin naturally produces vitamin D when it’s directly exposed to bright midday sun.
Are you meeting the four conditions for getting enough vitamin D?
But the challenge here is that this is not true in the winter for nearly everyone reading this. Unless you live in the tropics or subtropics, there simply isn’t enough UVB available to you in the winter to make vitamin D.
Even in the summer though, I wish I could tell you that just getting out in the sun takes care of your needs.
It’s certainly my preferred method to produce optimal levels, and research shows it is the most beneficial way to get your vitamin D.
It is one of the primary reasons I moved to Florida. My regular exposure to the sun allows me to keep my vitamin D levels in the healthy range.
However, with the factors I just mentioned – darker skin, over 50, gut issues, and weight – most people simply can’t get enough vitamin D from the sun.
And that’s not all…
To get the vitamin D your body needs for all its cells and tissues, four conditions must be met:
- You expose large portions of your body, not just your hands and face.
- You’re outside when UVB rays are at their peak, the only type of rays that produce vitamin D.
- You avoid the use of sunscreen during UVB exposure as it can prevent your skin from producing vitamin D.
- You’re in a latitude that has adequate UVB rays.
Many people believe taking a walk during a midday break fulfills their vitamin D needs, but you now know that is usually not true. And of these four conditions, the last one may be the biggest deal breaker of all…
Why You Have a GREATER Chance of Being Deficient Than Not
As you can see from the chart below, in most parts of the US (and the Northern hemisphere, including Canada), you can’t get enough sunlight to produce adequate levels of vitamin D in your skin.
Dr. Michael Holick, a recognized vitamin D expert, has found that if you live north of Atlanta, Georgia in the US, you cannot make vitamin D in your skin from about November through February.
Even as far south as Miami, Florida, you only make about 10 to 20 percent of the vitamin D in winter that you make during the summer months.
One exception to this rule is elevation… At 15,000 feet you can make robust amounts of vitamin D at northern latitudes, mainly because of the sun’s angle and because the sun has less atmosphere to penetrate.
One of the Biggest Mistakes Many People (Including Doctors) Make
with Vitamin D
Here’s another important fact you need to know about vitamin D: Vitamin D3 is not the same as vitamin D2.
Vitamin D3 raises and maintains your blood levels 87 percent better than D2
And taking the wrong one might do you more harm than good.
Vitamin D2 is not the type produced by your body in response to sunlight. The sun stimulates the production of D3, or cholecalciferol.
Ergocalciferol, or vitamin D2, was created in the early 1920s through ultraviolet exposure of plant foods and licensed to pharmaceutical companies.
Today, if you get a prescription from your doctor for vitamin D, it is likely to be this synthetic vitamin D2. It’s easy, even for doctors, to confuse the two forms.
I strongly advise you to avoid vitamin D2. In studies, vitamin D2 actually increasedmortality risk by 2 percent! And it binds poorly with proteins, making it less effective than D3.
Compared to vitamin D2, vitamin D3:
- Raises and maintains vitamin D3 concentrations 87 percent better
- Produces 2- to 3-fold greater storage of vitamin D in the body
- Converts 500 percent faster to the more active form that your body uses
Vitamin D3 is clearly the gold standard. Let’s figure out exactly how much you might need…
The Dangerous Advice That Can Leave You Woefully Deficient
A few years back, the US and Canadian governments asked the Institute of Medicine (IOM) to recommend daily amounts (RDA) of vitamin D for the general population.
They determined that most individuals needed only 600 IUs (International Units) of vitamin D3 to maintain serum levels of 20 ng/ml. And they concluded that everyday foods could provide those levels.
Two Canadian university investigators challenged their findings in 2014 and discovered a drastic error in the IOM’s calculations. They found the RDA for optimal health needs to be at least 10 times greater!
Nearly all vitamin D researchers agree that the recommended range for healthy “average” vitamin D3 levels is 40-60 ng/ml,not 20 ng/ml.
In the chart below, you can see how much vitamin D is needed to achieve various serum levels (top line). For example, if your current level is 20 ng/ml (in the first column), you need a daily dose of 5,000 IUs to raise it to 40, and 10,000 IUs to bring your levels to 60 ng/ml.
Source: Grassroots Health
Depending on your current test values, you may need a substantial dose of vitamin D – 10,000 IUs or more per day – to bring your numbers up into the optimal range.
Additionally there are genetic defects called vitamin D polymorphisms that a number of people have that prevent them from achieving optimum vitamin D levels with the doses described above. They may need many times that dose and the only way to know if you have this problem is to measure your vitamin D level.
So I strongly encourage you let your test values and the chart above be your starting guide for finding your ideal dose of vitamin D3, and not some arbitrary (and grossly inaccurate) numbers published by the government!