If someone has begun ingesting thousands of units of cholecalciferol daily, and is still not getting normal blood levels of the 1,25-dihydroxy form (or even any increase at all, as the writer states), in the vast majority of cases this doesn't mean they need to up their intake of cholecalciferol. Much more likely, it means they have liver and/or kidney disease that is preventing them from converting as much of the inactive form to the active form as they need.
My first thought was the stuff was phony. I would have thought a doc testing for blood levels of 1,25-dihydroxy vitamin D would have blood chemistry tests indicating liver or kidney dysfunction/disease already.
One would hope that a doctor would also be testing for kidney and liver problems, but after reading that piece, I’m not at all sure THAT doctor would, as he seems to be obsessed with pumping people full of huge doses of Vitamin D3. And there are other, harder to spot problems that could interfere with conversion of the inactive form to the active form.
Your body has “set points” and complex signalling systems, and will convert the inactive Vitamin D3 to the active form only when the parathyroid gland sends out a signal to the liver and kidneys to do this. It will normally do this when it detects low levels of calcium in the blood — but its notion of what constitutes “low” could be out of whack, in which case you can swallow a million units a day of inactive Vitamin D3 and it won’t have one iota of effect on your blood levels of the active form. Or you could have elevated calcium levels for some unrelated reason, and your parathyroid gland would refrain from calling for more active Vitamin D3. Your body might have very good reasons for keeping levels of the active form below what this doctor insists is optimal. The calcium regulation system is complex, and more often than not, the body knows what it’s doing.
When a doctor sees something like what was described in this piece — initiating supplementation of inactive Vitamin D3 at levels of 2000 to 4000 units daily, and seeing NO increase in blood levels of the active form — the proper interpretation is that the patient’s body is firmly refusing to activate more Vitamin D. The next step is to try to figure out WHY the body is refusing to do this, not to increase the already large dose of the inactive form by 100% or more. The sequence he’s suggesting is comparable to taking an emaciated patient who has had very little to eat in the past year, starting them on monitored feedings of 3000 calories a day, noting after a few weeks that the patient has not gained an ounce, and deciding that this means they must need 6000 calories a day.
Vitamin D3 is cheap, and unlikely to be fake unless you’re buying it from a street vendor in a third world country.