There's some research on Vit D and cholesterol, e.g.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4391213/

I'm not breaking any new ground; just adding a data point (n=1) that might be relevant to some people here on the forum ... and perhaps to future researchers.

My recent blood tests showed super-high LDL-C, a well-known phenomenon on this forum. It doesn't worry me in the least -- but I think it's an interesting puzzle so I continue to learn what I can. And, its worth noting that some of the most credible low-carb-friendly researchers think it (and/or the associated high ApoB and/or LDL-P, regardless of particle size) may still be an independent risk factor of some sort.

My same blood tests showed Vit D at 19 ng/mL, clearly meeting the 'deficiency' metric of < 20. I haven't looked in any detail at the physiology / chemistry, but apparently cholesterol is a precursor for the body to turn sunlight into Vit D.

So, a theory: my Vit D was low, so my body was making lots of cholesterol in the hopes that I'd get out from behind this computer screen into the great outdoors. (That's just idle speculation; the mechanism may be very different.)

In any case, getting both results at the same time suggested a great test. Instead of taking the prescribed 50,000 IU once per week, I took that 6x per week. (I did enough 'homework' to convince me that was safe, though I consider it excessive and wouldn't particularly recommend it to anyone else.) In any case, ~5 weeks later I got another set of blood tests.

Vitamin D: 144 ng/mL. Some references only get worried above 150; others above 100. I'm obviously going to back off on the supplements, which was my plan all along. But it quickly got high enough to test the effect.

And, though I gave it away in the title, the really interesting result: ApoB dropped 19%. (I didn't test LDL-C, LDL-P and the rest this time around since I think ApoB is a more interesting number.)

Except for some natural variation, there were *no* other changes in diet, exercise, sleep, stress, etc. during this time period.

So: if you're going to have blood tests done anyway, be sure to get Vit D tested. Or, if you arrive on this forum after you've already gotten 'scary' LDL-C numbers and your Dr wants you on statins, go back and get Vit D tested. Maybe a more modest 50,000 IU per week or 5,000 IU per day will get your Vit D up to levels that are good for other reasons, and bring down some of the lipid numbers that scare doctors. Or maybe not ... but it's an easy thing to try.

(FWIW, my ApoB number is still 'much too high' so my own search for info. continues.)

Very thought-provoking. Thanks for giving me something else worth investigating!

Very interesting research.

I'm currently taking 20,000iu of sublingual D (Sure Source NoShot) which is nicely keeping me in the optimal range until my next blood test.

I work in a dispensary and regularly advise customers to get both D3 and B12 levels checked out. It's remarkable how often this proves to be a background problem in niggling health issues.

Stella

Thanks, I had pretty scary LDL-C numbers at one point too, even though my Vitamin D was pretty optimal (about 60) at that point - but mine dropped like a rock when I finally was able to get switched from Synthroid to Armour natural thyroid. I only take 2000 IU of D3 daily to stay in a nice optimal level, but I do live in Florida after all.