Ive not noticed anything major since going 'cold turkey' to be honest, too early to ascertain changes in body fat.
As a side point, I used to notice that when i whan away on holiday(and had no omega 3 oil) that ive have less acne, but assumed this was due to lower stress levels.
I also used to grind flax, but i became suspicious that it too might provoke acne(lectins perhaps? i dont think thats been studied), but dont hold me to this! I do take hemp protein powder now and it works well for me.
I'll probably add back the fish oil in 2 weeks time and see if anything erupts!