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People are bad at reporting what they eat. That's a problem for dietary research

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Re: People are bad at reporting what they eat. That's a problem for dietary research

#301

Post by Sohcahtoa82 »

OkayPhysicist wrote: post #67
BoxFour wrote: post #34

Earlier quoted context omitted.

Why would that be a problem for reporting relative results if everyone is under-reporting things they're embarrassed about and over-reporting the opposite?

Different people are embarrassed by different things. A frat student's probably going to overstate their alcohol consumption, a Morman understate. People with bigger appetites underestimate their food consumption, people with smaller appetites overstate. Not to mention the degree of over/under statement will vary wildly. "A big meal" might be 300 calories for somebody with an eating disorder, or 3000+ for somebody on…

> "A big meal" might be 300 calories for somebody with an eating disorder

I knew a guy that complained that he "ate like a lion" and yet couldn't gain weight.

Turns out, his breakfast was typically a single egg and a slice of toast. Lunch would be half a sandwich and a bag of chips that he wouldn't finish. Dinner of course varied, but basically was like 4-6 oz of meat of some sort and a small side of veggies.

Overall, his daily calorie intake was probably only around 1,000 calories.

I don't know if this qualified as an eating disorder, or what, considering when we hear about someone undereating, it's because they're trying to lose weight. He was trying to GAIN weight and yet was still horrendously undereating.

Re: People are bad at reporting what they eat. That's a problem for dietary research

#302

Post by nemomarx »

xnorswap wrote: post #236
TypingOutBugs wrote: post #193

Earlier quoted context omitted.

Yeah I am doing 1g per lb of lean body weight and let's just say I have been eating a disturbing amount of egg white (I'm a big guy!) Getting protein in takes dedication & awareness

Isn't Whey powder a traditional "solution" for loading up on protein?

it's less than you'd hope. you need a fairly high volume of protein shake to get more than 40g of it in a sitting, and your target is probably like 100 or more grams of protein a day

I did a daily shake for a while as an after gym recovery food and I still had more calories from carbs than protein. it's just difficult.

Re: People are bad at reporting what they eat. That's a problem for dietary research

#303

Post by dacox »

It's an open secret that most nutrition research is of extremely low quality - almost all relying on decades old self reported nutritional questionnaires.

Sometimes dozens of these studies get wrapped up and analyzed together, and we headlines that THING IS BAD with a hazard ratio of like 1.05 (we figured out smoking was bad with a hazard ratio that was like 3! - you need a really good signal when you are analyzing such low quality data)

Re: People are bad at reporting what they eat. That's a problem for dietary research

#304

Post by wrfrmers »

everdrive wrote: post #81

A lot of people seem to have a purely emotional relationship with resources which logic doesn't seem to be able to penetrate. Food and finances seem similar here. For years I tried to get my wife to stick to a grocery budget. That is, we have $n per week for all groceries. She'd blow badly over the limit every time. "But we needed [food]" or "These were toiletries, so they don't _count_ as groceries." Ultimately we n…

Calories in -> calories out is flawed (or, rather, not useful) because metabolism is a feedback loop, not a one-way serial process. The types of foods you eat, how they're prepared, and when you eat them have complex influence for how hungry you feel and how much energy you have to exercise or resist impulses, as well as ramifications for the state of your physiology, per nutrient intake.

CICO helps explain weight management issues retrospectively, but it's inadequate with regard to planning, and for maintaining quality of life while working towards a weight management goal.

Re: People are bad at reporting what they eat. That's a problem for dietary research

#305

Post by tombert »

zahlman wrote: post #219
wnorris510 wrote: post #186

Earlier quoted context omitted.

Yeah, dividing out a known portion size is a good hack that will probably help with accuracy. In our research most people's calories and error came from eating out where they didn't have these hints, but this is a good trick if you mostly cook for yourself!

Historically I would rely on the restaurant's printed nutrition info. But I don't really eat out often enough for this to matter.

It can still be useful just to get rough estimates of what you're making at home, especially for portions and products that are roughly comparable.

If I make an egg, cheese, and sausage sandwich in the morning, and forget to weigh out or count how much of something I used, it can still be useful for back-of-napkin estimates if I Google the McDonalds Sausage McMuffin with Egg.

Obviously it's not going to be exactly equivalent, but I usually assume my homemade thing is 20% more than the restaurant to compensate.

It's of course better if you just weigh everything out first, you can get much more accurate measurements and calorie estimates then, but this can work in a pinch.

Re: People are bad at reporting what they eat. That's a problem for dietary research

#306

Post by OscarDC »

gadders wrote: post #45
valval wrote: post #37

Earlier quoted context omitted.

Tracking and weighing everything is a massive waste of time and energy. There are no obese animals (humans included) in the wild. Just stop eating the wrong things. I maintain a muscular 225 by eating dairy, eggs, and meat. If I want to drop down to 215, I drop dairy.

How old are you?

Not him but because your answer surprised me I chose to reply: at 34 it is also something I always wondered.

Becoming obese always seemed a little extreme to me and I fail to imagine how someone could reach that state without the accordingly extreme food-related habits - though maybe I'm just lucky to have the "right" metabolism and thus cannot relate.

Though even if obesity was always linked to eating disorders, I understand that "just stop" is not an appropriate response to that issue.

Re: People are bad at reporting what they eat. That's a problem for dietary research

#307

Post by nemomarx »

Sohcahtoa82 wrote: post #294
colechristensen wrote: post #278

Earlier quoted context omitted.

Also there are ways to convince your body that it needs less, and the journey from A to B is very uncomfortable. If you do it wrong you will just endlessly be suffering from your body thinking it's starving. On top of that though is you have to get over your intellectual ideas of how much food you think you need to eat.

This is so dismissive it's almost condescending. I know how much food I need to eat in order to survive and maintain a healthy weight. But if I eat that amount of food, I'm still hungry . Doesn't matter what I eat. I'll eat a diet high in protein and fiber, moderate in fat, and low in sugar and starches, which is supposed to be the recipe to feel full without eating empty calories, but it doesn't work. 16 oz steak pa…

I'm kinda convinced that something has changed (prescription meds ending up in the water supply? micro plastics?) that makes people hungrier than they were in the mid 20th century. the effort required to eat less seems higher than ever, and you can't totally explain the gap and rise in obesity with just lifestyle and food availability.

if some unknown element was making everyone's internal thermostat aim for more food it would explain a lot.

Re: People are bad at reporting what they eat. That's a problem for dietary research

#308

Post by nemomarx »

landtuna wrote: post #234
everdrive wrote: post #81

A lot of people seem to have a purely emotional relationship with resources which logic doesn't seem to be able to penetrate. Food and finances seem similar here. For years I tried to get my wife to stick to a grocery budget. That is, we have $n per week for all groceries. She'd blow badly over the limit every time. "But we needed [food]" or "These were toiletries, so they don't _count_ as groceries." Ultimately we n…

I never understood why calories in == calories out was relevant when we can't know how many unprocessed calories are remaining undigested. Here's what the bots had to say: https://www.perplexity.ai/search/weight-loss-gurus-often-say... (FYI - I stay thin by limiting calories, so I don't disagree that fewer calories causes weight loss)

cico is true, but you can't measure calories in accurately and you can't be sure of calories out accurately. isn't that fun?

(in practice as you know, you just kinda do it on feel and end up restricting calories enough to lose weight. but my own intuition is that I had to aim for 100 or 200 less than my estimated BMR so the math is very fuzzy isn't it?)

Re: People are bad at reporting what they eat. That's a problem for dietary research

#309

Post by nemomarx »

colechristensen wrote: post #288
nemomarx wrote: post #258

Earlier quoted context omitted.

yeah, you want to force yourself to do some activities that keep your metabolism up along with the restrictions you can't exercise out of a bad diet but exercise is a helpful supplement to a good diet too. it's just that making yourself do it when you're tired and hungry is draining.

>you can't exercise out of a bad diet You can, but it's not easy. People who exercise _a lot_ often have trouble eating enough calories. 5,000 to 10,000 calories a day is hard to eat and not out of reach. I knew a guy who was drinking a gallon of whole milk a day for a while to try to maintain weight.

I really can't imagine having the energy to burn 10k a day - what kinda workload were they doing?

Re: People are bad at reporting what they eat. That's a problem for dietary research

#310

Post by pkaye »

foxyv wrote: post #240
UomoNeroNero wrote: post #200

Earlier quoted context omitted.

I have been diabetic for 20 years. I have tried every method, app, plan, and tool, including systems falsely marketed as "smart." No method works or delivers decent results except for using a scale and weighing ALL the ingredients. For a diabetic, eating "out" is always a roll of the dice. The "fun" feedback from post-meal blood sugar is always a reminder of how "eyeballing a plate" is utterly useless.

It doesn't help that food manufacturers intentionally make it hard to measure nutrition from most of their foods. They play around with serving sizes to hide carbohydrates making you have to do math just to keep up. Sometimes they will round down on grams of macros after setting the serving size so they can claim it has zero sugar when it does in fact have tons of sugar. Tic-tacs are the worst about this. They claim…

The rounding rule is carbs https://foodlabelmaker.com/regulatory-hub/fda/rounding-rules...
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