"There's only one hard and fast rule in running: sometimes you have to run one hard and fast."

Wednesday, October 13, 2010

Maybe it's NOT just calories in, calories out

Today I heard of a study which, not only haven't I read, I can't even find. So, of course, I presume to discuss the contents, as blog standards are lower than closing-time standards. Supposedly, groups of mice were given the same amounts of food and exercise, but differing amounts of light; those mice receiving the most light ended up weighing most. It leads to an interesting idea.

There's a camp of fitness experts who say one should not eat after 8 PM (or 6, or some other arbitrary time), as calories then get turned into fat. Others say that that's completely idiotic, as weight loss is simply a matter of calories consumed minus calories burned. Now there's a third possibility; it doesn't matter so much when you eat, but if you're keeping lights on when it's dark, you're screwing with how your body metabolizes food. The standard idea was that, if you're sitting in front of a computer or television screen at night, you're not moving and you're probably eating and that's why you're gaining weight; the new idea is that your body is more efficient in the light, so you're getting more calories from the same amount of food.

It's a possibility. Light cues are important - there's circadian rhythms, there's vitamin D production, there's melatonin secretion... light does more than allow one to see. There's also some validity to the idea of differences in efficiency; there was a time when dieters were told that celery and lettuce were "free foods," as they provided fewer calories than it takes to eat them; also, there was once a fad of eating cold foods, as the body has to provide calories to heat them to body temperature (and conversely, there are those who advocate spicy foods, as breaking out in a sweat from hot foods burns a few calories). No one's ever connected the two things, however.

The thought continues: Americans have grown fatter as we've spent more time in artificial light in times that are normally dark. First it was television, then it was computers, but there's also ambient light in cities from street lights and security lights, to having digital alarm clocks facing beds to having devices that have small lights to show that they're plugged in even if not turned completely on. The rest of the world is going the same direction as technology (and comparable wealth) spreads.

It might be one more thing to add to the arsenal of weight loss: turn off the lights at night.


Andrew Opala said...

I read another study in the same way where mice were asked what University they chose to attend and many later died from cancer in another study!

I like the idea of turning the lights off - but people are fatter because food is plentiful.

The best way is to start converting all the food we have into fuel for cars - then people will be hungry, but they will still be able to sit in traffic with the A/C on for 2 hours!

Thanks for the Pre wisdom!

Ewa said...

I never believed calories in calories out equation. Then I hear Dr Oz talk about poop and the amount of... fat in it. That means that we do not metabolize all the fat, right?
The equation is much more complicated than.
Too much light in our lives apparently messes up with many parts of how our bodies work.

sea legs girl said...

Something sounds weird. How do you ensure that the rats get the same amount of exercise? How do they exercise in the dark? I can't help feeling the mice in the light weighed more because they had more muscle from running around freely in the light.

Another option is the mice in the light were retaining fluid from increased cortisol levels - due to lack of sleep and other hormonal imbalances. In which case the extra weight was water.

I still believe in calories in, calories out. But it sounds like an interesting study.

Glaven Q. Heisenberg said...

"Calories out"? Call it what is is, you Typical Elitist Mid-Western Arugula-Eating Egghead Perfesser!

It's POOP!

sea legs girl said...

Mr. Glaven,

It is NOT poop. It's fuel that we burn. That's why we don't eat our poop. At least that's the only reason I can think of.

RBR said...

I like the lights off, or REAL dim, but I am not sure that actually makes me thinner, more of an illusion.

Oh, wait, you weren't talking about sex?

Glaven Q. Heisenberg said...

@RBR - Oh, wait, you weren't talking about sex?

Well, I am ... now ...


O, sure! My word verification word is "rapan". I said "sex"! who said anything about "rape"?

But then again ... nothing wrong with a little role-playing ...


shannon said...

Individual metabolic disorders aside, body weight is the result of energy consumption vs energy expenditure. Modern day conveniences have allowed much of the population to become increasingly sedentary. We have created technology/devices to minimize physical effort (calorie expenditure) while maximizing activities that consume few calories.

P.S. Nice to "hear" you at the TC10/TCM! :)