Rahel
While I'm still a skeptic about nutrition therapy, the Vitamin D catch was perceptive of her.  I too have very low cholesterol so both my cardiologist and my endocrinologist urged me strongly to take 4000 IU of Vitamin D every day.   Neither were impressed by the recent negative study on Vitamin D but felt the ones you referenced were more valid.  The results of my blood tests showed a big jump from 25 ng/ml to 44 (optimal levels on lab tests are over 30 up to 100).  With just two pills a day, you can have your cake (High Vitamin D) and eat it too (keep that low cholesterol)
Thought you would want some positive reinforcement 
Keep the faith
Charm