At first, I thought it was attributable to other factors. In real life, most people don't modify one factor at a time.
They reduce
processed carbohydrates/eliminate wheat and cornstarch
lose weight
add or increase omega-3 fatty acids from fish oil
begin niacin
increase exercise and physical activity
All these efforts also impact on HDL.
Among the many things I do, I consult on complex lipid (cholesterol) disorders (complex hyperlipidemias) in my office. A substantial number of these people carry a diagnosis of
hypoalphalipoproteinemia, a mouthful that simply means these people are unable to manufacture much apoprotein A1, the principal protein of HDL cholesterol particles. As a result, people with hypoalphalipoproteinemia have HDL cholesterol levels in the neighborhood of 20-30 mg/dl--very low. They are also at high risk for heart disease and stroke.
Encourage these people to
exercise, attain ideal weight, eliminate wheat and cornstarch: HDL increases 5 mg/dl or so.
Add niacin, HDL increases another 5-10 mg/dl.
Perhaps we're now sitting somewhere around an HDL of 35-40 mg/dl--better, but hardly great.
Add
vitamin D to achieve our target serum level . . . HDL jumps to 50, 60, 70, even 90 mg/dl.
The first few times this occurred, I thought it was an error or fluke. But now that I've witnessed this effect many dozens of time, I am convinced that it is real. Just today, I saw a 40-year old man whose starting HDL was 25 mg/dl increase to 87 mg/dl.
Responses like this are supposed to be impossible. Before vitamin D, I had
never witnessed increases of this magnitude.