Not at all. Loose skin is what happens when someone drops a dramatic amount of weight regardless of how much or how little time it takes to lose that weight. After a certain point in the weight loss, skin isn't elastic enough to "shrink to fit".

Not all the time - MzMegs is actually kind of right. The slower you lose the weight, the more chance you give your skin a chance to regain it's elasticity. People who lose more than 4-8 lbs a month put themselves at risk for it (realistically I think yu have to lose 4 or less a month). That's not to say stretch marks wont all disappear (they do lighten considerably). But think about it with pregnant women. Yes, some get that saggy post pregnancy skin, some seem to be able to get their pre-pregnancy body back to a degree. Oh, and I've lost 110 lbs and never had excess skin. I did it over a two year period (losing 4 lbs a month thereabouts). I went from 250 to 140. But it all depends on genetics, the person, height, etc.

165, It's almost completely down to the genes. Losing weight fast or slow doesn't play a part. 162 is right on the mark.

The OP didn't say how it was lost, so how do you know it wasn't natural? And losing 65 pounds is a lot. If you lose 65 pounds, no matter how it's done, there will be some extra skin to deal with.