This press release is copyrighted to the journal Obesity.

Weight gain may depend on when you eat

Weight gain may be influenced by meal timing, according to a recent study of obesity in mice. The findings, reported online this week in the journal Obesity, suggest that eating at irregular hours during the body’s natural circadian rhythm may contribute to increased weight gain.

The body’s natural circadian rhythm regulates, among other things, internal sleep and wake cycles with respect to external dark and light cycles. Though many dieters are warned against late-night eating, there has thus far been no link between the timing of food intake and increased weight gain. Recent studies have found the body’s internal clock also regulates energy use, suggesting the timing of meals may matter in the balance between caloric intake and expenditure.

Investigating this hypothesis, Fred Turek and colleagues found that mice that were fed during normal sleeping hours gained more weight than mice eating the same type and amount of food during naturally wakeful hours. The findings could contribute to a better understanding of how meal timing and the body’s circadian rhythm regulate energy and in turn weight gain in humans.

Source:
http://www.nature.com/press_re...ty_press_release.pdf

Also see:
http://www.time.com/time/print...8816,1920374,00.html

This message has been edited. Last edited by: Sheltieguy,

My brother-in-law has been a 3rd shift ICU nurse for about 20 years. I think he actually weighed more when he worked and lived the 9-5 lifestyle. He eats the same number of meals and the same amount and types of food as he would if he still did work a day job. He is also a runner, so that helps too. I would guess that in the transition from a day job to a night job and vice-versa may initially impact eating habits and weight, once your body is in a routine and your internal clock is re-set, you would be just fine.

Jill

I'm not sure about shift workers... My brother works from 6pm to 4am, and there is no way to tell with ONE human being, but MOST of his weight issues are WHAT he eats, not the tme of his meals. (And in this study... they intentionally overfed the rats high fat food to force them to gain weight...)

With the rest of us, who are usually up in the day and sleeping at night...

I've found that if I sleep 8 hours a night (10:30pm to 6:30am), I'm not eating at midnight or 1am simply because I'm asleep and for MOST healthy people, it is physically impossible to eat while asleep.

If I stay up until midnight or 1am... I often get hungry when I'm tired. But I think that a huge factor is that I'm hungry, simply because it has been 5-6 hours since dinner. I'm ALWAYS hungry 4 or 5 or 6 hours after a meal. The only exception is while I'm sleeping.

I've noticed this is often the case on various boards. People who eat at night, usually don't have a regular bedtime and don't value getting 7 or 8 or 9 hours of sleep. They stay up late, and are hungry at midnight. And as the Taco Bell ad goes, "It is time for the 4th meal". Eat an extra meal every day (or night) and a person is going to have weight issues.

If a person is saying that they have trouble with late night snacking... a good question is, "How many hours do you sleep a night? Why were you up? Why weren't you in bed, sleeping?"