It's also important to allow for some treats. Fitness trainer Autumn Calabrese, creator of the 21 Day Fix and 80 Day Obsession, said, "You also need to be consistent with your healthy eating. That doesn't mean you have to be perfect all the time, but you do have to be on top of it. I like the 90/10 rule. I know a lot of people say 80/20, but if you're really trying to lose weight, then 90 percent of the time, you need to be eating healthy, clean food in the proper portions." That leaves 10 percent for the foods you crave that may not be so healthy.