Car smokes until warmed up. Diagnosis?

I have a 1991 mazda 626. It smokes for a little while until it starts warming up. It seems to be worse the colder it gets outside. But after it warms up it doesn't smoke at all. When I start it up cold and it smokes, it bellows out pretty good.. The smoke appears to be whitish, maybe slightly blue? The car does consume some oil, and there are no leaks, it consumes much less oil after starting to use that "engine restore" silver can stuff, and it also doesn't seem to smoke for as long after starting it up. However I would like to know what the issue is and how much it may cost to have it fixed? The car is pretty old and beat up and has over 200k miles, yet is very reliable. Just trying to see if it might be worth even fixing. Maybe a valve job?