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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

#121

Post by myheartisinohio »

aziaziazi wrote: post #29

For those that "track and weight everything" (how ?) do you manage ?: - sauces you make yourself? I often mix some different oils, mustard, seeds, miso, bit of leamon juice and spices… but weighting and logging everything will take 3x the time to do the sauce itself - different cooking time in one receive : oignons going first, tomato sauce in the middle and parsley at the end (but still cook a bit with residual heat…

I use myfitnesspal and try to get close. There is a lot of data in the database. It is a tool like anything else it just helps me eat more intentionally.

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

#122

Post by acuozzo »

aziaziazi wrote: post #29

For those that "track and weight everything" (how ?) do you manage ?: - sauces you make yourself? I often mix some different oils, mustard, seeds, miso, bit of leamon juice and spices… but weighting and logging everything will take 3x the time to do the sauce itself - different cooking time in one receive : oignons going first, tomato sauce in the middle and parsley at the end (but still cook a bit with residual heat…

This probably doesn't count, but I pretty much eat the same thing every day. I think being pretty far along the autistic spectrum makes this easier for me than most.

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

#123

Post by jcranmer »

Sebb767 wrote: post #9
f1shy wrote: post #2

Just a couple of days ago, I wrote I automatically flag any submission with any kind of "dietary" studies. I'm not saying there is no one study well done, but doing it well, is just (almost) impracticable. Not only the people have literally no idea what they eat, they forget and misreport, also a human living normal life in the society has just TOO MANY variables. There is no way to keep the other variables like, spo…

> There is no way to keep the other variables like, sport, social interaction, stress and such out of the study. Sure, but with sufficiently many people, these effects will usually average out. I'm not saying the situation is great, but it's still an important field of study and we need to make progress in some way.

> Sure, but with sufficiently many people, these effects will usually average out.

In the case of dietary studies, not really. There are a few factors which are known to have a big effect on your health--being wealthy, active, and moderate in particular--and a lot of the big studies are really just uncovering yet another proxy for those factors.

Of course, you can turn that around and make the realization that your diet doesn't really matter: there's no diet that will magically make up for being a couch potato. And outside the main well-known interventions (e.g., eating less calories), the solution is generally to just be more active and things like that rather than trying to tweak your diet.

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

#124

Post by FollowingTheDao »

The bigger problem with dietary research is that it does not take human diversity and genetics into account.

See : Genetics, Nutrition, and Health: A New Frontier in Disease Prevention

https://www.tandfonline.com/doi/abs/10.1080/27697061.2023.22...

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

#125

Post by StefanBatory »

skerit wrote: post #61
drchiu wrote: post #44

Another way to look at it is that tracking what you eat is very difficult. Currently trying to lose a few pounds and doing calorie tracking. Practically carry a scale and a calorie tracking app with me. About once a day there's still some "estimation" involved due to the fact that all the ingredients are mixed together.

Indeed. I also tracked everything I ate for a long time, many years ago. As soon as you eat something made by someone else you're basically guessing.

Then write it down as x2-x2.5 of what you'd expect. Better to eat less the following day than overeat.

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

#126

Post by robertlagrant »

beezlebroxxxxxx wrote: post #106
robertlagrant wrote: post #98

Earlier quoted context omitted.

> I don't recommend it to people with an ED history Your daily reminder that ED means more than one thing.

The little blue pill is probably in MyFitnessPal if one really wants to track all their macros.

I wonder if any fitness watches can tell when their wearer's had one.

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

#127

Post by MegaDeKay »

aziaziazi wrote: post #29

For those that "track and weight everything" (how ?) do you manage ?: - sauces you make yourself? I often mix some different oils, mustard, seeds, miso, bit of leamon juice and spices… but weighting and logging everything will take 3x the time to do the sauce itself - different cooking time in one receive : oignons going first, tomato sauce in the middle and parsley at the end (but still cook a bit with residual heat…

I use Cronometer (www.cronometer.com) and a scale. It lets you create recipes with the weight of each item and the weight of the final result. I then weigh the portion I have with a meal. Why do I do this in the first place? I'm one of those people that eats too little vs too much, especially in the summers when I'm outside all day burning tons of energy: tracking calories helps me keep weight on. I have to eat so much food to maintain my target weight that it gets pretty uncomfortable some days. Yay for muffins and cookies.

Don't worry about how leftover nutrients decrease over time: you'll get enough nutrients in a well balanced diet without having to worry about the minutia. If you're really worried about it, pop a multivitamin for cheap insurance.

Also don't worry about the variation in calories between one type of cucumber / apple / whatever vs. another. Those variations aren't significant and they probably average out anyway. Realize too that the sources aren't exact in the first place: once source is likely to give a different caloric value for something like dried beans vs another.

If you're going to track, don't get too caught up worrying about if the absolute value of the calories you're recording is 100% accurate because even if they were, you can't track your energy expenditure 100% accurately. If the bathroom scale goes in the wrong direction for you, adjust your caloric intake to compensate. Look at trends over the week and over the month vs day to day variations and it won't take long to zero in on the right number for you.

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

#128

Post by constantcrying »

BoxFour wrote: post #80
OkayPhysicist wrote: post #67

Earlier quoted context omitted.

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…

Sure, but in a representative sample size this is largely irrelevant. The fraternity brothers and the Mormons cancel each other out, and regardless both are dwarfed by the large middle of the population that likely systematically and reliably under-reports their drinking by a few units. The idea of outliers and systematic biases isn’t new to statistics, relative comparisons are still useful.

>Sure, but in a representative sample size this is largely irrelevant.

There is no way to know whether your sample size is representative. What amount of fraternity brothers and Mormons cancel each other out?

>and regardless both are dwarfed by the large middle of the population that likely systematically and reliably under-reports their drinking by a few units.

And? That does not prevent spurious correlations.

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

#129

Post by rat9988 »

aziaziazi wrote: post #29

For those that "track and weight everything" (how ?) do you manage ?: - sauces you make yourself? I often mix some different oils, mustard, seeds, miso, bit of leamon juice and spices… but weighting and logging everything will take 3x the time to do the sauce itself - different cooking time in one receive : oignons going first, tomato sauce in the middle and parsley at the end (but still cook a bit with residual heat…

Sauces are quite easy in practice. Usually you can measure in table spoons or whatever.

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

#130

Post by wnorris510 »

I've done research in this space for many years at Google AI and now at SnapCalorie. The thing I find interesting is how confident people are in their ability to estimate portion size visually, and in truth how wrong they all are.

We published in CVPR (top peer reviewed academic conference for computer vision) and people are on average off by 53% and even trained professionals are still off by 40%. Basically if you want to have a higher level of accuracy you need to use a food scale or something that measure the volume of food, people just can't estimate portion sizes visually.

Oils, cooking fats, hidden ingredients are what people are most concerned about but they actually add far less error to people's tracking than portion. Nutrition5k is the paper we published if you want to check out more details on the breakdown of error most people get when tracking.

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