What affects how much you eat?

[Influential Panda]

I've got a 500g scientific balance accurate to .01 grams, a couple hundred dollars in funding, and about 60-100 students I can experiment on. So, if anyone has a hypothesis they want scientifically tested and analyzed, shoot.

Some existing research, for inspiration:

People snack more when the candy jar is clear rather than opaque.
People eat more when the container is bigger (popcorn box, plate, cup)
People eat more in larger groups of people (it's almost perfectly linear--about 92% more in groups of 7+)
People eat faster with fast music
People pour more drink in short and wide glasses than tall skinny ones

I'll figure out a way to construct a design out of your idea. I just wanna hear your opinions.

ETA: Mod, fix the title? This is driving me bonanza.

[JustThinkin']

How 'bout correlating what causes (genetics, nurture, emotional health) some folks to eat when stressed and some folks to lose their appetite?

[Santo Rugger]

I eat more when I'm hungry.









But seriously, what determines my hunger is how much I've exercised lately. I'm a growing boy, you know!


Sucks that all the growing has been horizontal lately, but them's the breaks.

[Leaffan]

I heard a radio show about this recently, and the size of container and group of people phenomena are completely accurate.

Thinking about this, I have a feeling that I would typically eat more when a meal is prepared for me, rather than having to prepare it myself. This isn't always the case, of course, but somehow it's better to hear "supper's ready" and sit down to a meal, than have to scrounge through cupboards and make myself something.

[aruvqan]

Originally Posted by Leaffan

I heard a radio show about this recently, and the size of container and group of people phenomena are completely accurate.

Thinking about this, I have a feeling that I would typically eat more when a meal is prepared for me, rather than having to prepare it myself. This isn't always the case, of course, but somehow it's better to hear "supper's ready" and sit down to a meal, than have to scrounge through cupboards and make myself something.

Really? before I was diabetic and controlled my diet I would eat more grazing around looking for a mean than if someone made it for me ... little of this, little of that, ooo a brownie .... where a meal someone else made was given to me as specific portions ...

[The Devil's Grandmother]

I heard a radio show interview with the guy who wrote Mindless Eating: Why We Eat More Than We Think which was quite interesting. I don't recall whether or not he looked at food consumption in large groups, but there's some interesting bits on other items in your list.

[ivylass]

I think eating family style (everyone serves themselves out of big dishes rather than getting served individual portions) makes a difference. I just can't remember which way.

I'm pretty sure people eat more at a buffet. How about do people eat more when there are more choices?

[Vox Imperatoris]

I eat more snacks when I'm doing something else that occupies my main focus, but that's not too intensive. Like posting on message boards. *eats Twizzler*

Valete,
Vox Imperatoris

[Rigamarole]

I'd submit the tastiness of the food as a factor. It's a lot easier to eat a bunch of triple-chocolate fudge cake than the calorically equivalent amount of gruel.

[devilsknew]

Seperate a bunch of M&M's by color. Put them in seperate jars, let the kids choose and eat them and find out what color of food is most appealing by extenuation. I'm guessing red will be the most popular, brown the least. - Eating with the eyes, berries and meat.

[devilsknew]

Then again that's a pretty simple one... pretty sure it has already been tested.

[devilsknew]

I'm pretty sure people eat less if there are animals present... Due to the fact that they might feed the animals some of their food. But what would be interesting to know is if they eat less or more around animals in general without feeding them.

Maybe animals stimulate appetite due to our carnivorous nature?

[Karyn]

I read something somewhere that of course I can't find the source for now, but it wasn't a scientific study by any means. They claimed that people ate far more when the remains of what they had already eaten (bones, fast food wrappers, empty dishes) were taken out of sight than if they were left on the table. I tried it out on my partner and it had no effect whatsoever except to get annoyed that I kept fussing around disappearing things. You could try to find out if there's any truth to it.

[Jodi]

I'd be interested to know if people eat more when watching TV or reading or engaging in another distracting amusement. (I'm guessing yes.) I'd also be interested in knowing if the type of distraction makes a different -- again, I'm guessing people eat more when watching TV than when reading.

[Influential Panda]

Keep 'em coming, y'all. Even if you list something that's been tested, I can be your "ask the dude who's read way too much about motivational psychology" on the topic.

Originally Posted by Karyn

I read something somewhere that of course I can't find the source for now, but it wasn't a scientific study by any means. They claimed that people ate far more when the remains of what they had already eaten (bones, fast food wrappers, empty dishes) were taken out of sight than if they were left on the table. I tried it out on my partner and it had no effect whatsoever except to get annoyed that I kept fussing around disappearing things. You could try to find out if there's any truth to it.

Brian Wansink tested it, and it was about as scientific as it gets. He got waiters to bus away chicken wings and empty glasses, and weighed the amount they ate with reminders and without. They ate a lot more without visual cues of how much they've eaten.

Originally Posted by ivylass

I think eating family style (everyone serves themselves out of big dishes rather than getting served individual portions) makes a difference. I just can't remember which way.

It's called "fat family" style, and it's bad because people tend to eat the majority of what they serve themselves. Also, if they're accustomed to going for seconds, the visual cue of "hey, empty plate, stop eating" means they're going to continue eating past the point of necessity.

Originally Posted by ivylass

How about do people eat more when there are more choices?

Yep. Wansink again, studying M&Ms. People at more when there were all the colors vs when there were just one or two colors.

Originally Posted by Rigamarole

I'd submit the tastiness of the food as a factor. It's a lot easier to eat a bunch of triple-chocolate fudge cake than the calorically equivalent amount of gruel.

Schachter in the 70's. He gave people milkshakes either laced with quanine (bitter) or not, and recorded how much they ate. Normal BMI people drank a little less with the quanine, and Obese BMI people ate almost none with the quanine, but almost all of the milkshake without. The conclusion is that the Obese tend to be affected by flavor more, giving weight to the addage "never trust a skinny chef."

Originally Posted by devilsknew

I'm pretty sure people eat less if there are animals present... Due to the fact that they might feed the animals some of their food. But what would be interesting to know is if they eat less or more around animals in general without feeding them.

That's actually a fascinating idea. This might be worth looking into. I'll have to root around in some journals to see if there's any corresponding research, but it's a simple design and applicable to a lot of people.

Originally Posted by Jodi

I'd be interested to know if people eat more when watching TV or reading or engaging in another distracting amusement. (I'm guessing yes.

It's been done, and the answer is "yup." When you're distracted, you pay less attention to internal cues that tell you to stop eating. There's also not a lot of visual cues to tell you stop consuming, i.e. an empty plate or beer bottle.

[Duke]

Originally Posted by Jodi

I'd also be interested in knowing if the type of distraction makes a different -- again, I'm guessing people eat more when watching TV than when reading.

I guess you can use two hands to eat while watching TV, but you only have one hand free while reading. That right there is going to cut down on consumption while reading, no? Hey...we could get grants for this kind of insight! Lovely.

[dactylic hexameter]

Could you look at the effect of room temp on food consumption? ie, you're in a cold room, you have increased thermogenesis, which some how stimulates caloric intake, and you therefore eat more. An adaptation of that - does being cold stimulate you to eat more carbohydrates (instant energy for heat production), or more fat (hm, winter's coming, lets store some calories away), or both?

[tdn]

One I've heard about but would be hard to test is if people eat more on vacation. In one respect, absolutely. Screw the diet, I'm all about the fun. But another aspect is that when you're away from home, you go into survival mode. Not only do you subconsciously eat more, you process calories differently.

[overlyverbose]

Originally Posted by aruvqan

Really? before I was diabetic and controlled my diet I would eat more grazing around looking for a mean than if someone made it for me ... little of this, little of that, ooo a brownie .... where a meal someone else made was given to me as specific portions ...

This is what I do, too. Also, at one point I ate most meals, which were low in calories and pre-portioned, in my car, so when I got home, it was a luxury to be able to sit down and eat something really fatty and junky. There are a bunch of other factors that fed into gaining the weight - most of it was that it was so insidious. Unfortunately, that habit continued for a few years after grad school ended. I was losing it, then I got pregnant.

Anyway, back to the above - like aruvqan, I've found that if someone pre-plates my meal, I'll eat that portion and nothing else. On the other hand, if someone serves food family style - with large serving bowls of food on the table - I'll eat more. Or if I haven't planned a meal and am looking around for something to make, I'll absently start munching and, by the time I have my meal made, I've already eaten enough calories for a full meal.

[Whiteknight]

This must have been tested already, but how about testing the effect of how much others around the subject eat? I'd imagine that there is a strong "acceptability" factor when it comes to deciding when to stop.

[Sigmagirl]

That is definitely it for me. I know that many people eat when they're lonely, but I never snack when my husband is not home. When he is home and gets out the cheese crackers, I always have some. I don't blame him for my gaining weight, but I can attribute it partially to his presence.

[puddleglum]

How about whether the price of food affects how much is eaten?
Do people eat more when food is accompanied by alcoholic beverages?
Do people eat more if they think the food is organic?
How does eating with strangers affect amount?
Are there smells that affect how much is eaten?
Will eating a salad with the meal affect how much dessert is eaten?

[devilsknew]

It would help to know what kind of academic setting this would pertain to. You say you have "students"? Elementary School, High School, College?