Experience has taught me to accept the 80-20 Rule.
The 80-20 Rule states that as long as you’re eating whole foods 80% of the time—and otherwise living a healthy lifestyle—you can get away with eating anything you want the other 20% of the time.
I have found this to be true.
In practice, the 80-20 Rule means the average person can probably stay lean despite eating just about anything one day a week.
Call it a “cheat day.”
It’s worked for me. For the past ten years, my regular diet has been strictly whole foods. But once or twice a week, I’d eat anything I wanted. And what I wanted was the Fat Four.
Despite these fairly regular junk-food excursions, I maintained significant weight loss the entire decade.
Many trainers and dietitians have similar experiences, both with themselves and their clients. Human metabolism seems to be regulated by the foods we regularly eat. It’s what you do most of the time—your eating habits—that seems to have the biggest impact on your weight. If you’re only eating whole foods most days, you can probably get away with a weekly cheat day.
But your mileage may vary. The 80-20 Rule assumes you’re exercising regularly, sleeping well, and mostly eating great. It’s not a free pass to indulge. And some people can get away with more than others.
Still, studies have found that, compared to people with rigid diet rules, so-called “flexible dieters” tend to lose more weight, have better weight-loss maintenance,1010,1011 less depression and anxiety,1012 and less frequent and severe binge-eating episodes.1013
In other words, understanding that you’ll mess up sometimes and not being too hard on yourself—the essence of the 80-20 Rule—is associated with more weight loss.
You don’t have to say goodbye to the Fat Four forever, or even for weeks at a time. You just have to say goodbye to the Fat Four most days of the week.
The way to think about junk food is “later,” not “never.”
This is a more sustainable, practical, and effective attitude.
Some gurus recommend designating a particular cheat day each week. Say, every Saturday. This can be effective for some people.
But for me, “life happens” at unpredictable times. I just try to avoid the Fat Four every day, with the understanding that I’ll mess up sometimes.
Do whatever works for you.
You don’t have to be perfect. You won’t be perfect.
If you eat whole foods about 80% of the time, you can probably eat whatever you want the other 20% of the time. This works out to one or two “cheat days” per week, on average.
It’s fine to enjoy yourself sometimes.
1010. Westenhoefer et al., “Cognitive and Weight-Related Correlates of Flexible and Rigid Restrained Eating Behavior,” Eating Behaviors 14, no. 1 (2013): 69-72.
1011. Smith et al., “Flexible vs. Rigid Dieting Strategies: Relationship with Adverse Behavioral Outcomes,” Appetite 32, no. 3 (1999): 295-305.
1013. Westenhoefer et al., “Validation of the Flexible and Rigid Control Dimensions of Dietary Restraint,” International Journal of Eating Disorders 26, no. 1 (1999): 53-64.