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

science.org

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

#11

Post by elektrolite »

TypingOutBugs wrote: post #6

I try calorie count with My Fitness Pal and holy shit it’s a lot of effort. Eat out and you’re screwed (estimated at best). When you include sauces and oils etc it’s really hard to be accurate in the best of times, and it’s just a pain to keep on top of. Best option is to avoid any so you don’t have to count. I imagine almost everyone will add bad data in a study at some point with the best of intentions.

I think being consistently inaccurate helps. If you always get the same thing at a certain restaurant, you can start by giving your best estimate of the calories in that meal. Then if your average weight doesn't move in the direction you want you can adjust your target calories to compensate.

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

#12

Post by thefz »

Everything needs to be weighted on a precise scale, every ingredient and not just the macros. On top of that the reported nutrition values on labels can be wrong by a large margin so for not whole foods, we introduce an error.

This is why calorie counting is ballparking to get us a general idea, and not a precise science.

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

#13

Post by xnorswap »

TypingOutBugs wrote: post #6

I try calorie count with My Fitness Pal and holy shit it’s a lot of effort. Eat out and you’re screwed (estimated at best). When you include sauces and oils etc it’s really hard to be accurate in the best of times, and it’s just a pain to keep on top of. Best option is to avoid any so you don’t have to count. I imagine almost everyone will add bad data in a study at some point with the best of intentions.

> Best option is to avoid any so you don’t have to count

This is why one of the best ways to lose weight is to just keep a food diary / count calories. You don't need any special / fad diet, just the act of trying to keep a note of everything you eat will cause you to stop and think, "I don't need to eat this".

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

#14

Post by constantcrying »

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.

No they won't. If you have two correlated factors and only measure one of them you can easily get to totally wrong conclusions.

If you have a food that is more often eaten by people doing a lot of sports, you will measure that eating that food is correlated with being more healthy. But it would obviously be fallacious to conclude that this food is more beneficial to health than other foods.

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

#15

Post by switch007 »

TypingOutBugs wrote: post #6

I try calorie count with My Fitness Pal and holy shit it’s a lot of effort. Eat out and you’re screwed (estimated at best). When you include sauces and oils etc it’s really hard to be accurate in the best of times, and it’s just a pain to keep on top of. Best option is to avoid any so you don’t have to count. I imagine almost everyone will add bad data in a study at some point with the best of intentions.

Lean into that

And even if you don't record with 100pc accuracy, there's still a lot of value

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

#16

Post by XorNot »

guerrilla wrote: post #5

I just weight and scan erything. The only problem is eating out. Mobile apps make this very easy today. They should be using them and scales that automatically report, with photo documentation, etc. Skip self-reporting and go straight to self-measuring.

Do you have scales which self-report because this has been on my wish list for a while now? It seems like it should exist: scales with a BLE read out that dumps out the value after a number has been stable, and flags it if I hit a button on the scale.

There's a whole range of products here which seem like they should exist but just don't (but I hardly want to do a hardware startup).

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

#17

Post by bluGill »

BoxFour wrote: post #3

Does this actually pose an issue for most studies? This seems like it would be an issue for any studies relying on absolute food consumption being accurate. Most studies I come across frame their findings in relative terms (likely for this very reason): Individuals who engage in more of X compared to their peers show a correlation with outcome Y. For example, if you’re trying to determine whether morning coffee consu…

most people are embarrassed about the truth. So they will over report vegetables while not mentioning how much alcohol or tobacco they had (or illegal drugs which the study probably legally must report to the police). Or a self proclaimed vegetarian will not report meat they ate despite their claim. fat people will report they skipped desert.

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

#18

Post by lm28469 »

> Is coffee good for you? What about wine or chocolate? Scientists trying to answer these questions

There is a virtually infinite amount of cofounding variables, genetics, meal timing, fitness level, sedentarity, &c. . It's a 80/20 type of problem, do the 80, forget about the 20, you'll never be able to get your answers anyways.

If you look and feel like shit you're most likely eating like shit. If you look and feel good a glass of wine every now and then or a bite of chocolate after dinner won't do much.

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

#19

Post by lukan »

xnorswap wrote: post #13
TypingOutBugs wrote: post #6

I try calorie count with My Fitness Pal and holy shit it’s a lot of effort. Eat out and you’re screwed (estimated at best). When you include sauces and oils etc it’s really hard to be accurate in the best of times, and it’s just a pain to keep on top of. Best option is to avoid any so you don’t have to count. I imagine almost everyone will add bad data in a study at some point with the best of intentions.

> Best option is to avoid any so you don’t have to count This is why one of the best ways to lose weight is to just keep a food diary / count calories. You don't need any special / fad diet, just the act of trying to keep a note of everything you eat will cause you to stop and think, "I don't need to eat this".

Consciouss eating.

One can (and should) extend that concept to anything. Be conscious about what you do. Then you likely know, if you are not doing good - and can change it.

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

#20

Post by XorNot »

xnorswap wrote: post #13
TypingOutBugs wrote: post #6

I try calorie count with My Fitness Pal and holy shit it’s a lot of effort. Eat out and you’re screwed (estimated at best). When you include sauces and oils etc it’s really hard to be accurate in the best of times, and it’s just a pain to keep on top of. Best option is to avoid any so you don’t have to count. I imagine almost everyone will add bad data in a study at some point with the best of intentions.

> Best option is to avoid any so you don’t have to count This is why one of the best ways to lose weight is to just keep a food diary / count calories. You don't need any special / fad diet, just the act of trying to keep a note of everything you eat will cause you to stop and think, "I don't need to eat this".

This is what happened to me when I needed to lose weight. The act of counting calories more or less completely revamped my diet in a positive way.

Turned out I was also stupidly deficient on protein day to day.

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