Have you ever wondered why almost all nutrients are expressed by weight in milligrams or micrograms…but instead, vitamin D is expressed in “international units” or IU?
I know I certainly have. And I know I’m not alone…
Truthfully, I suspect it has something to do with the government-industrial-medical complex wanting everyday doses of vitamin D to sound absurdly high.
But before I get into my not-so-outlandish conspiracy theory, let me give you some context by running through some basic scientific method…
Metric system makes it easy
The scientific world uses the metric system to express mass (in grams), volume (in liters), and length (in meters).
Scientists adopted the metric system after the French Revolution in 1793. It’s based on ratios of 10s ¾ perhaps going back to the most ancient number system of utilizing all 10 fingers. This adoption also replaced archaic and inconsistent systems of measurement and currency, which were based on arbitrary sizes and couldn’t be easily converted.
Today, the decimal-based metric system is used in almost all scientific measurements. (Except in measuring vitamin D, as you’ll see…)
Here’s a quick recap of the metric system of weights:
Gram
One gram: Used as the base unit of measure for weight.
Kilogram
One thousand grams: Used to measure units of mass at the human scale, like the human body.
Milligram
One-one-thousandth of a gram: Used to measure units of mass at a small scale, like nutritional supplements.
Microgram
One-one-thousandth of a milligram (one-millionth of a gram): Used to measure units of mass at a microscopic scale.
Nanogram
One-one-thousandth of a microgram (one-billionth of a gram): Used to measure units of mass at a smaller microscopic scale.
Without wanting to sound like Carl Sagan, there are billions and billions of nanograms in a kilogram.
What does it all mean for you?
You typically take dietary supplements and drugs in milligram quantities (and, occasionally, micrograms). These supplements or drugs then dissolve within the human body, which is made up of kilograms (of mostly water). This process weakens the concentration and vastly dilutes the nutrient or drug.
For instance, when milligrams of a supplement are dissolved in kilograms of water, it makes for concentrations that approach extreme dilutions. Homeopathic preparations use these same extreme dilution quantities.
Spices and herbs used in cooking fall a little higher on the concentration spectrum. Generally, we consume them in gram quantities.
Interestingly, you can take the same herb as a supplement (taken in milligrams) or as a condiment (taken in grams). This relationship shows how relatively safe it is to consume herbs ¾ which are also foods ¾ as supplements.
By comparison, you could never take drugs in “food” quantities.
So, that whole explanation brings me back around to the question of why “international units,” or IU, are used to measure vitamin D?
Measurements for vitamin D destined to confuse
International Units, or IU, don’t refer to mass or volume that we can see or feel, as in the case with milligrams or micrograms. Instead the IU measures the potency, or biological activity, of a compound. They measure physiologic activity.
But why even bother with something arbitrary like IU…especially when every other supplement is measured according to mass?
And not to mention, the use of IU as it pertains to vitamin D makes the doses seem very high.
As you know, I recommend 10,000 IU of vitamin D daily. Initially, that number can cause some hesitation in taking such a “high” dose.
But what does 10,000 IU translate to in terms of mass?
10,000 IU of vitamin D is just 250 micrograms (in “actual weight” terms)!
That’s 25 millionths of a gram. And just one ten-thousandth of the typical minimum dose for a common vitamin or herbal supplement. That amount is much lower than a typical-sized dose of any other supplement ingredient.
It’s almost comical how the government will tell us not to worry about parts–per-million (ppm), or parts-per-billion (ppb), when it comes to toxic pesticides in foods and consumer products. Yet the government wants doctors and patients to think taking any amount over 4,000 IU of vitamin D (a measly 100 micrograms of an essential nutrient) is “high.”
Blood levels of vitamin D even smaller
We now use nanograms (one-billionth of a gram) to measure actual levels of vitamin D in the blood.
In fact, when I first started working in laboratory medicine as a pathologist, clinical chemist and toxicologist at the McDonnell Douglas lab (which was using top-of-the-line NASA technology), it was impossible to measure anything in the blood or tissues in such small “nano” levels.
Those limitations could’ve very well been a part of the ongoing problem when it came to measuring vitamin D in clinical labs.
And yet, the government worries about “high” doses and levels of a healthy nutrient like vitamin D — which ultimately translates to levels less than 100 nanograms in a milliliter of blood.
Each 100 IU of vitamin D you ingest raises blood levels by just one nanogram per milliliter (nmol/L). When you think about it, it’s amazing how much the body can do with such a small amount of vitamin D.
Be sure you know your blood levels. Ask your doctor at your annual check-up to test your vitamin D levels with a 25(OH)D test. Ideally, you want your levels to be between 50 nmol/L and 75 nmol/L.
The amazing vitamin D
As you know, the skin makes vitamin D when exposed to natural sunlight. What’s even more amazing is that natural sunlight actually destroys any excess vitamin D the body happens to make. That’s why you can never have too much vitamin D (especially since your liver and fat tissues store it).
So, let’s not be fooled by the international units that make vitamin D doses “seem” high, when they’re not high at all; especially when compared to other dietary supplements or to drugs.
These false appearances contrived by the mainstream can now put this medical myth to rest — it is extremely rare that you will ever “overdose” on vitamin D. In fact, clinical vitamin D intoxication is one of the rarest medical conditions in the world.
Vitamin D doses may “seem” high but they are not. Like Hamlet says to his homicidal mother, about how things appear, or how they seem, versus reality: “Seems, Madame?…I know not ‘seems.’” (Act I, Scene 2)