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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

#41

Post by lm28469 »

tomrod wrote: post #23
lm28469 wrote: post #18

> 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…

You reduce the uncertainty of the remaining 20 by substantially increasing sample size across a randomly selected sample. Unfortunately for these studies you have multiple selection criteria that are nonrandom: (1) interest in the study (2) adherence to protocol of the study (3) reporting back in If nutrition science wants to be serious, their N should not be in the 10s but rather the 10,000s. That has an expense, bu…

Until they track absolutely everything including each trial subject microbiome, hormone profile, &co over time, I still feel it just won't cut it.

Plus it doesn't even matter what is true for the statistical average, given the infinite amount of variables and outcomes one glass of wine might be statistically beneficial but absolutely terrible for your own health because you have one specific gene combination or one specific microbiome mix. Which means you'd have to go through the same regimen of analysing and tracking all the parameters for yourself for it to be applicable

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

#42

Post by chikere232 »

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…

Macros are pretty stable though. A week old veggie has less vitamins than a fresh one, but the carbs are pretty unchanged. Trying to measure and weigh for micro nutrients seems doomed though.

As a way of life, weighing and counting macros also seems pretty doomed to because it's just so much work, but it's very doable for a few days to realign your view of what an appropriate amount of food is, if you're diligent and mindful enough to not have a soda or a snack without thinking

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

#43

Post by djtango »

oersted wrote: post #28
thefz wrote: post #12

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.

I find the way we measure calories very interesting: place the food in a metal box filled with oxygen, immerse the box in water, make the food explode so that it combusts completely, and finally measure how much the water heats up. Rather crude and fun, but that's it, see Bomb Calorimeter. I guess it makes sense in retrospect, how else would you do it? They usually just measure standard basic ingredients, then you ro…

I'm not convinced calorimetry is particularly useful for any nuanced diet planning.

We can't eat wood (or coal) but they're very calorific when measured via bomb calorimetry.

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

#44

Post by drchiu »

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.

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

#45

Post by gadders »

valval wrote: post #37
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…

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?

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

#46

Post by Refusing23 »

thats a problem for research that relies on food questionaires and thats been known for a while, and probably why there's even a thing called 'the french paradox' and so on.

but i get it

it's expensive to do properly, and so its not really done that often, and when it happens there's usually only a few participants.

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

#47

Post by dkdbejwi383 »

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…

adjusting seasoning/tasting as you go seems like it would complicate matters too, especially if you're in the heat of it and don't have time to stop and weigh that extra pinch of salt etc

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

#48

Post by Pooge »

thefz wrote: post #12

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.

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

This is true, because of "caloric availability".[1] If you took that into account, you would have a better idea of how many calories your body is absorbing.

[1]: https://x.com/gilesyeo/status/1084463469997555717

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

#49

Post by liveoneggs »

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…

All of those headlines are based on meta-studies putting together 100 junk studies, based on bad data, which then informs actual medicine and health trends and American X Association and...

For your specific example - "morning coffee" could be anything from plain espresso shot to full 600+ calorie starbucks "coffee" but the meta-study-machine will lump them together.

It's kind of like feeding all of reddit's comments into chatgpt, asking it about stuff, and trusting its answers at a society-level with your health on the line.

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

#50

Post by chikere232 »

jjj123 wrote: post #33
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…

For me I mostly just try to log the high macro and/or calorie items. Like if I make a Caesar dressing I’m mostly counting the oil and if I’m being really meticulous I’ll measure the Parmesan and anchovy content. But I’ll ignore the 2tbsp lemon juice, garlic, mustard, etc. since it’s counting so little towards the totals I care about. If you’re trying to measure your vitamin intake this may not work for you, though.

For vitamins are probably easier to start in the other end and have a blood test to check how you're doing. I have no idea if that would involve selling your first born in the US though
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