My doctor and most references say to take it with the evening meal. I had been taking it 2000iu at lunch and 5000iu at dinner as sort of a compromise thinking I should spread it out. All my meals have fat.
I've also read about co-factors such as K2, magnesium, and calcium, also zinc. I think K2 and magnesium are the most important.
My mom just told me LEF says do NOT take D without K2, could actually increase cancer risk. for what it's worth