Overnight Fasting Brings Big Gains for Fat Loss

A study in the journal Cell Metabolism found enforcing a late-night food curfew could help you burn fat without dieting.

Researchers here discovered that mice confined to an eight-hour feeding period became leaner and healthier than mice that casually ate throughout the day.

Here’s the story. They divided the mice – all of which shared the same genes, gender, and age – into one of two groups. Both groups ate the same mice equivalent of pizza, Ben & Jerrys, and beer.

But their meal timing was different. One group ate whenever they wanted. Because mice are nocturnal, these guys put away half their food at night and otherwise casually noshed throughout the day.

The second group, however, could only eat within an eight-hour window every night. In other words, for 16 hours every day, these mice fasted.

Bad news for the mice that chowed down 24/7: after 100 days, they became fat with high blood sugar, cholesterol, liver damage, and with deteriorating health.

The fasting mice, on the other hand, weighed 28% less and – you guessed it – were in glowing health.

Oh, and guess which group won the exercise contest? Yep, the fasting mice.

I’ll repeat that again: both groups ate the same crappy diet, just at different times.

“It’s a dogma that a high-fat diet leads to obesity and that we should eat frequently when we are awake,” said senior author Satchidananda Panda. “Our findings, however, suggest that regular eating times and fasting for a significant number of hours a day might be beneficial to our health.”

These researchers suggested people could get the same metabolic benefits as the eight-hour mice by putting the brakes on eating after dinner until the next morning’s breakfast.

You’ve probably heard about intermittent fasting (IF), where you voluntarily forego food for a certain period of time. Besides numerous health benefits, proponents claim IF is a great way to burn fat.

The concept is nothing new. Even in the early 60s researchers noted that people could become and stay lean by doing one water-only fast every week, which allowed “them to be more liberal with their diet on the other days.”

Hunger is a powerful force. And despite these benefits, walking around famished and cranky all day is absolutely no fun. That’s a big reason you might be reluctant to try IF.

Which makes this study so relevant and interesting: by doing most of your IF while you’re asleep, you can get its benefits without suffering hunger or deprivation. At worst, you might have to surrender your midnight snack.

So you could have a big dinner at 6 p.m. and then resume eating the following morning at, say, 9 a.m. In other words, you’ll be “fasting” for about 14 hours, which gives your body enough time to shift into serious fat-burning mode.

Now, I’m certainly not suggesting you have an all-you-can-eat deep dish and cheesecake dinner and then expect your fat to melt away.

But if you’re stalling with your current eating plan (maybe your low-carb diet has hit a plateau) or want to burn a few pounds before your two-week trip to Kauai, you might want to give this overnight fast a try.