A friend told me this story.
Her friend, Linda, had added vitamin D to her daily supplements. Because she'd had a vitamin D blood level of 22 ng/ml, she was taking 6000 units per day.
However, Linda also had a high cholesterol value with a total cholesterol of 231 mg/dl. After several months on the vitamin D, she had another cholesterol panel. Total cholesterol: 256 mg/dl.
"It must have been the vitamin D! So I stopped it right away."
Is this true? Does vitamin D raise the level of blood cholesterol? Yes, it does. But it's a good thing. Let me explain.
Followers of The Heart Scan Blog know that total cholesterol is really a mix of 3 other factors:
Total cholesterol = LDL cholesterol + HDL cholesterol + triglycerides/5
This is the Friedewald equation, still used today in over 95% of cholesterol panels. So, by the Friedewald equation, anything that increases LDL, HDL, or triglycerides will increase total cholesterol.
One of the spectacular changes that develops over a year of taking vitamin D is that HDL cholesterol skyrockets. While sensitivity to this effect varies (probably on a genetic basis), HDL increases of 10, 20, even 30 mg/dl are common. A starting HDL, for instance, of 45 mg/dl can jump up to 65 or 70 mg/dl, though the effect requires up to a year, sometimes longer.
Vitamin D can also reduce triglycerides, though the effect is relatively small, usually no more than 20 mg/dl or so. Likewise, the effect on LDL is minor, with a modest reduction in the small type of LDL.
So the dominant effect of vitamin D from a cholesterol standpoint is a substantial increase in HDL. Looking at the equation, you can see that an increase in HDL is accompanied by a commensurate increase in total cholesterol. If HDL goes up 25 mg/dl, total cholesterol goes up 25 mg/dl.
So Linda is absolutely correct: Vitamin D increases cholesterol--but it's a good thing that reduces risk for heart disease and is an important part of a coronary plaque-reversal program.
This is yet another reason why I advocate elimination of total cholesterol on lipid panels. There is no useful information in the total cholersterol value, only the potential for mis information.