The safe assumption: No. Can lights are like little volcanoes. They give off a tremendous amount of heat which can start fires if they come into contact with the paper backing of fiberglass insulation. Not only that, but loose-fill insulation is made from paper products. Definitely combustible.
"Insulation-Contact" Can Lights - a Solution?
There is a type of can light that is rated "IC" for "insulation contact," and what it means is that the manufacturer has designed the lights so that a piece of metal flashing or mesh keeps insulation and other combustible materials away from the bulb. I must admit that even that makes me nervous, given the proximity of paper to those high temperature lights.
Best advice is simply to limit your usage of can lights, because they are notorious energy-wasters.