Protein doesn't cause cancer, any that's not used is excreted in urine lol and yep I agree with the carb cycling. Only high carbs when trying to gain mass and carb cycling for a cut, high carb on training days and low carb on rest days works best. I would say though that for guys we need to be 12% body fat at the most for abs with 8-10% for a ripped look and 6% for the competition look.