First off, if you're so skeptical, then at least get a 25(OH)D level blood test. If you're under 32 ng/ml (80 nmol/l) that's bad. You don't even get the absolut

First off, if you're so skeptical, then at least get a 25(OH)D level blood test. If you're under 32 ng/ml (80 nmol/l) that's bad. You don't even get the absolute minimum necessary not to get sick very often. The benefits start showing up from 40 and above. Strongest benefits seem to be around 55 ng/ml, and toxicity starts around 66 ng/ml. To get to 40 ng/ml you need around 9000 IU (240 mcg) per day. So get your test, see that you're deficient (very likely), and then I would suggest starting on 5,000 IU per day. Then 6 months later, take another test. See if you've at least passed 40 ng/ml. If you haven't, I'd suggest going to 10,000. Then 6 months later do the test again. See if you're anywhere near the toxicity level. If you aren't, keep taking 10,000, and do the test in another year. See if anything has changed. This could save your life or at least make you feel way better every day (kind of like how we feel when we're bathing in the sun). See my other comment here for more details on this Vitamin D issue.