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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

#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, sport, social interaction, stress and such out of the study.

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

#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 consumption correlates with longevity it doesn’t seem particularly relevant if you believe everyone is underreporting their food intake, as the article implies; it's a relative comparison.

Sure, those findings often get twisted into clickbait headlines like “X is the secret to a longer life!” but that’s more a popular science problem than an issue with dietary research itself.

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

#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.

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

#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.

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

#7
I thought this was generally known that people are bad at reporting most things about themselves. It's a good argument in favor of wearables or other smart monitors, if anyone expects to do actual rigorous research it needs to be objective.

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

#8
> many studies of nutritional epidemiology that try to link dietary exposures to disease outcomes are founded on really dodgy data

I wonder if the data are always skewed in a particular direction. For example, do people typically underreport junk food and overreport salads? Or do they omit entire meals? Or snacks?

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

#9
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.

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

#10
post #9
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.

It only averages out if the factors are unrelated though. If a lot of asians eat rice and don’t have a high alcohol tolerance, your study would still show a correlation between eating rice and alcohol tolerance when looking at every single person on earth.
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