Is Timing Important for Weight Loss?
Recently, I mentioned that the time one turns in for bed may play a role in how easily one falls asleep. Research suggests that night-owls, who stay up into the wee hours, have more trouble falling asleep than early-to-bed folks. I also talked about some of the health risks associated with staying up too late. A tendency to gain more weight is one such side effect.
As it turns out, part of the problem has to do with late-night snacking. We used to think that when it comes to maintaining healthy body weight, the only thing that really matters is calories. All calories are the same, we thought. It doesn’t matter what form they take, or when they’re consumed. Calories in, versus calories out (burned for energy). That’s all that matters, we believed. Except it’s not that simple. The workings of the human body, with its complex metabolic processes, cannot be described by a single, simple thermodynamic equation.
We now know that some calories are unequal. Some of this has to do with the digestive system’s ability to extract calories from food. Wouldn’t you know, many high-fiber, whole plant foods contain more calories that are actually available to us. Much of this effect depends on the activity of gut bacteria. This is not true of refined sugar, of course. Those calories are all-too-readily absorbed into the bloodstream. They trigger wild oscillations in insulin and blood sugar levels, and set the stage for greater hunger and more cravings…and more overeating.
Now, say researchers at the Salk Institute for Biological Studies, it has become apparent that calories consumed late at night are handled by the body differently than calories consumed at other times of the day. Working with mice, scientists discovered that, even though subjects ate the same number of calories daily, overall, mice that consumed a portion of those calories late at night invariably got fatter than their lean counterparts, who only ate during waking hours. Investigators called the latter “time-restricted feeding”.
It’s a strategy that could be adopted by humans looking for an edge in the battle of the bulge. Incidentally, it didn’t seem to matter if the food consumed was high in fat and sugar, either, provided it wasn’t consumed late at night. Even when mice were given weekends off to eat whenever they pleased, the differences remained. "The fact that it worked no matter what the diet, and the fact that it worked over the weekend and weekdays, was a very nice surprise," says the study's first author Amandine Chaix.
Will you change your snacking habits at night to try to cash in on this latest news? I’d love to hear about your challenges or successes.
Amandine Chaix, Amir Zarrinpar, Phuong Miu, Satchidananda Panda. Time-Restricted Feeding Is a Preventative and Therapeutic Intervention against Diverse Nutritional Challenges. Cell Metabolism, 2014; 20 (6): 991 DOI: 10.1016/j.cmet.2014.11.001