'Gut Rest': How It Works
Compared with other kinds of diets, night fasting is simple.
The first meal of the day is most beneficial only if it comes after 12 to 14 hours of not eating or drinking.
The new research suggests that breakfast really is the most important meal of the day—but we need to embrace its original meaning: breaking a fast.
In addition to fasting at night, it’s beneficial to eat your main meal earlier in the day.
In a 2013 study, Harvard’s Frank Scheer and Marta Garaulet of the University of Murcia in Spain analyzed 420 dieters at weight-loss clinics. Participants ate the same number of calories and were equally active, but those who had their main meal before 3 p.m. lost significantly more weight than those who ate later. “To find such big differences in weight loss with just a slight difference in meal timing is quite remarkable,” says Scheer.
Tricks to Use the Food Clock to Lose Weight
1. Fast for at least half of each day. Try not to eat for at least a 12-hour span daily. Ideally your fast would begin after the evening meal (from 6 to 8 p.m.) and extend until breakfast (8 a.m.).
2. Eat breakfast like a king and dinner like a pauper. A 2013 Israeli study put overweight and obese women into two groups. Both had the same number of calories, but one ate a large breakfast, a medium lunch, and a small dinner; the other had a small breakfast, a medium lunch, and a large dinner. The large-breakfast group lost more weight and showed a stronger improvement in metabolic health metrics.
3. Forgo late-night noshing. A 2015 study found that an evening meal raises people’s blood sugar levels 17 percent more than does an identical meal eaten in the morning. Related research found that the number of calories people burn digesting food in the first two hours after a meal drops by half if they eat the meal in the evening versus the morning
4. Consume only water during your fast. Anything else will start your body clock. Put off that morning coffee until after your 12-hour window.
5. Adjust to your natural rhythms. Early birds might want to eat supper at 6 p.m. and fast until 6 a.m. or later. For night owls, it might be easier to have dinner at 9 p.m. and fast until at least 9 a.m.