ADF involves a 24-hour cycle of eating normal amounts of foods (2,000 calories), followed by 24 hours of serious calorie restriction, with no more than 500 calories on fasting days. The theory goes that all the misery of fasting becomes more bearable, knowing that after a day spent nibbling on a piece of lettuce, you get to eat whatever you want. (And a side of fries.) In other words, you’re only on a “diet” half of the time, while the other half doesn’t feel like a diet at all.
Proponents suggest ADF makes the ever-popular fasting/cleansing approach more sustainable for long-term benefits. It also gives you some power over your social calendar, since you’re only “dieting” every other day. And, according to University of Illinois at Chicago research, it's effective: Dieters on a modified ADF plan shed 10 to 30 pounds in eight weeks.
There are other possible pluses, according to Ariane Hundt, a nutritionist, personal trainer, and founder of the Brooklyn Bridge Boot Camp. On fasting days, she says, the digestive system gets a rest, blood sugar levels balance out, and energy levels can be regulated. “With fasting, you can teach your body to become more sensitive to calories from sugar and starches, so that when you do eat them, you'll have a more negative response,” says Hundt. “You learn to dislike those foods and create an aversion rather than seeing them as a treat.”
But, what are the long-term effects of this binge-and-deprive approach to food — and can someone even diet this way as a lifestyle? Studies are inconclusive at the moment, and experts who weigh in tend to agree that this type of eating only reinforces an extreme, all-or-nothing relationship with food. “If you were to eat a lot of sugary calories one day and then none the next, you would simply undo a bad day of eating without making any true progress," Hundt says.
What's more, without a focus on nutrition, ADF disregards any guidelines for replenishing those essential nutrients that aren't taken in on fasting days. “This approach simply doesn't teach you about the impact of foods on your body,” adds Hundt. “You don't learn anything about food and health, and you don't learn how to eat properly to create a healthy body and mind. It simply perpetuates the diet model, which isn't working in the long run.”
Our take? While ADF has its benefits, it can encourage an extreme relationship to food. A well-balanced, nutrition-focused way of eating is more our style.
Photo: Via Muji