By the time you leave work, hit the gym, head home, and throw dinner together, it's practically already time to hit the sack. Sound familiar? While eating a late dinner is the reality for many of our go-go-go lifestyles (hey, at least we're eating one!), a new study published in Cell Metabolism shows it may also sabotage our waistlines, further suggesting that timing really is everything when it comes to healthy eating.
Researchers at the Salk Institute in San Diego subjected some 400 mice (at various weights) to different diets—one high in fat, one high in fat and sugar, and one high in sugar. Regardless of the diet plan, the mice that ate within a 9- to 12-hour timeframe developed less body fat than their counterparts that had the whole day to eat, even though they consumed the exact same number of calories.
"Your body clock ensures that metabolic enzymes are ready for the cycle of consuming food, storing energy, fasting, and burning energy," says Amandine Chaix, a postdoctoral researcher at Salk Institute, and author of the study. "If you eat at an improper time, you disturb the system, and your body may not metabolize the calories you consumed as efficiently."
The best part? The researchers even weekend-proofed their theory (when most diets get tossed to the curb), giving the time-restricted subjects two days of full access to high-fat meals. Still, these mice gained less weight than their always-free-wheeling counterparts. "The fact that it worked no matter the diet, and the fact that it worked even when taking a break on the weekend, was a very nice surprise," says Chaix. The researchers say this suggests that the time-restricted diet can withstand some temporary interruptions (read: when life gets in the way).
Ready to test the time-restriction idea on yourself? Schedule your mealtimes as best you can, making sure your first and last meals of the day are within 12 hours of each other.