I have a cheat weekend every two weeks how much impact do you think that will have on my weight loss.. usually pizza, ice cream etc?

It depends...: This depends on how good your diet is the rest of the time & how much you cheat- a slice or 2 of pizza & a couple tablespoons of ice cream is a lot different than a whole pizza & a pint of ice cream. If you eat well most of the time a bit of cheating now & then should not be a big problem, but cheat in moderation! my favorite diet: http://www.Drfuhrman.Com/library/what-is-a-nutritarian-diet.Aspx.