The common sense rule for best vitamin benefits

I don’t get on Facebook often, but I did last weekend in time to see the funniest meme a friend shared. You may have seen it too since it’s really blowing up. It went like this…

If you think you’re smarter than the previous generation… 50 years ago the owner’s manual of a car showed you how to adjust the valves. Today, it warns you not to drink the contents of the battery.

Is that a hoot or what — and so true, right?

You can’t pick up any product these days without finding not only instructions on how to use it, but warnings on how not to — all because one person did something most people with common sense wouldn’t dream of …

Like that British guy who took amounts of vitamin D so insanely high, he ended up in the hospital. How does that even happen?

Too much of a good thing and not enough common sense

After listening to a private nutritionist on a talk show, this gentleman reached out. He wanted vitamins and wanted to get healthy. Vitamin D deficiency is estimated to be around 40 percent. It may be even higher in the U.K. where they have fewer sunny days. So, he started out to do something that made sense…

But ended up doing something that didn’t: Taking 50,000 IU of vitamin D three times a day, for a commonsense-defying total of 150,000 IU daily!

After about two months of this, he wound up hospitalized with hypervitaminosis D — or overdose of vitamin D. According to the Mayo Clinic taking 60,000 IU daily of vitamin D for several months can cause toxicity. This guy really cut to the chase!

He had lost 28 pounds and his kidneys were in big trouble. After eight days of treatment, including for hypercalcemia (too much calcium), he was released and his doctors planned to continue monitoring him.

Understanding vitamin D recommendations

Now I’ve tried to do some digging because I’m not sure if this guy’s nutritionist really made this insanely high recommendation to him — or if he thought, “the more, the better.” We may never know the full story.

Maybe he got confused. In the US, doctors prescribe 50,000 IU weekly (NOT daily, NOT X3) for 8 weeks to treat deficiency, then drop down to about 1,000 IU per day.

But while it’s not at all surprising to see more experts recommending amounts higher than the existing RDA of 600 to 800 IU — like the ones who pleaded for higher levels during the pandemic — they certainly aren’t anywhere near what the British man was taking. Not even in the same ballpark.

Take the Guidelines from the Endocrine Society, which refer to the current RDA as the minimum — and note it’s not even known if those minimal amounts confer the full bone and musculoskeletal benefits associated with vitamin D.

Instead, they suggest at least 1500 to 2000 IU daily and at least 4000 IU in the winter months. For those who are overweight or obese, they suggest two to three times more (we know vitamin D benefits and metabolism differ based on body weight — so it’s not a one-size-fits-all situation).

A decade-long hospital study supplemented 4700 patients starting at 5000 IU and none of them experienced hypercalcemia or any other adverse reaction. Again, a common sense amount nowhere near what landed that British chap in the hospital.

About now you may be wondering… If these amounts I’ve just outlined are above the RDA yet considered safe, how did we get stuck with such a low RDA to begin with?  

Even scientists can be bad at math

In 2015 researchers at UC San Diego and Creighton University challenged the intake of vitamin D recommended by the National Academy of Sciences (NAS) Institute of Medicine (IOM), stating that their RDA for vitamin D underestimates the need — by a factor of TEN!

When they discovered the calculation error, they brought it to the attention of the IOM in two separate studies — but were ignored.

Still, the UC San Diego researchers called “for the National Academy of Sciences (NAS) and Institute of Medicine (IOM) and all other public health authorities concerned with transmitting accurate nutritional information to the public to designate, as the RDA, a value of approximately 7,000 IU of Vitamin D a day from all sources.” To clarify, that recommendation was for adults, only — and “all sources” include supplements, sun and diet.

And that is how 5000 IU of vitamin D3 became the suggested daily “therapeutic” dose for adults.

But there’s one common-sense piece of advice I need to add, so no one follows in that British chap’s footsteps…

When supplementing, choose from a trusted manufacturer and follow the guidance on the serving size, printed clearly on the label.

Sources:

How an increasingly popular supplement landed a man in the hospital — CNN

Recognition and Management of Vitamin D Deficiency — AAFP.org

Recommendation for vitamin D intake was miscalculated, is far too low, experts say  —Science Daily

Endocrinologists release vitamin D Guidelines — ASHP Foundation

Daily oral dosing of vitamin D3 in long-term hospitalized patients: Insights from a seven year experience — J Steroid Biochem Mol Biol