Magnus Lygdback – who trains the likes of Alicia Vikander, Gal Gadot, and Katy Perry – swears by the 17/20 rule.
"17 out of 20 meals should be on point, and you should enjoy life three out of 20," he told PopSugar. "So it's up to you when you want to do those three meals out of 20, but that's my philosophy."
"How many women do you know who can have a slice of pizza and not have a guilty conscience? I don't know many," he said. "Food is a big part of life, and it should be enjoyed."
His ethos is similar to the popular 80/20 rule, which involves consuming a healthy, balanced diet 80 percent of the time and indulging 20 percent of the time. It’s proponents (and many experts) say that this style of eating is far easier to stick to long term.
But if you can keep track of the last 20 meals you ate, the 17/20 rule could work for you.