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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

#141

Post by shadowtree »

As someone who just lost 35 pounds through clean dieting:

All calorie/portion numbers on packaged food are off by 10-20%. I set MyFitnessTracker to 1.5k calories (deficit for my build) and for weeks nothing would budge - even with strict portion control and weighing everything, plus 800 extra cals spent through exercise.

Once I went to "1250" calories, I started losing weight. Went from to 205 to 175 pounds.

With packaged food I mean anything like cream cheese, various sides, etc. - not pre-built meals (I assume those would be off by 50%).

What weighing your food really does, is reveal how shockingly little you actually should be eating. I switched to small plates for all meals, as using the normal large ones was pointless and slightly de-motivating.

But yeah, it's just calories. No matter what you eat.

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

#142

Post by f1shy »

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.

No if they correlate strongly: people eating more vegetables are more likely to do sport, and care about sleeping. Not to mention visiting a doctor much often. That is just one example.

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

#143

Post by mmooss »

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…

> For whatever your metabolism, and whatever your category of calories, fewer calories will still produce weight loss.

I thought that wasn't true, that the human body stores and burns calories at varying rates based on many signals, and that our bodies or some bodies effectively conserve weight or caloric stores at a certain level.

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

#144

Post by LPisGood »

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 don’t do this anymore, but when I was, the answers are as follows:

I didn’t make a ton of sauces myself, but if it was then I would round spices down to zero and weigh the main caloric components (think mayo, soy sauce, sugar, oil, tomato paste, etc)

I always weighed the uncooked food, so different cooking times was a non factor.

As for nutrients decreasing, I dealt with this by not believing in it. Seriously though, I was tracking fats, carbs, and proteins which to my knowledge do not meaningfully decay in non negligible amounts.

I lived alone so I didn’t often have to cook for multiple people. When I did I would just make 2 omelets or waffles or whatever and weigh mine.

As far as different species/cultivation methods, I realized there was an absolute edge to my ability to track. For example: bread is often listed at 70 calories per slice, but if you weigh each slice, you’ll find it deviates from what the package considers a “slice” of bread substantially. Further, you’ll often find packages that are inconsistent. For example, you might see a box that claims 14g of a food is 5 calories but the entire 28g container is also listed at 15 calories.

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

#145

Post by nemomarx »

agos wrote: post #118
crazygringo wrote: post #100

Earlier quoted context omitted.

> - sauces you make yourself?… but weighting and logging everything will take 3x the time to do the sauce itself Yup, it will. Nobody said tracking nutrients was quick. > - 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) Cooking time doesn't matter for macronutrients. > - Leftovers nutrients decrease with time The…

> Yup, it will. Nobody said tracking nutrients was quick. well, many say it's "easy" (it's not)

tbh it's "easy" if you're also doing a pretty specific focused diet. (maybe simple would be a better phrase - it can be reduced to very simple steps. mentally choosing to do this and enduring it is difficult, but the process itself is straightforward.)

like the worry about sauces is true but if you eat mostly chicken and rice and one slice of bread a day you can really get that variability down. when I was heavily restricting I would only cook very simple things like that and otherwise eat packaged food, and it certainly worked to lose weight. but you sacrifice variety and flavor and you'll feel kinda stressed and hungry for months at a time.

the last factor is living with people who are not dieting - I personally think this makes the required willpower basically impossible. if there is food in the house you will eventually succumb to the temptation of eating it in my experience. it's much easier if you live alone and only have the diet food in the house at all, buying nothing else, etc.

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

#146

Post by mmooss »

llm_nerd wrote: post #89
damnesian wrote: post #40

This is why sleep studies are conducted in clinics, not left to patients to self-report. they want accurate data? They will need to conduct a real study, portion the meals out themselves, give people a schedule.

Such studies do exist - randomized feeding trials. In these studies the participants are provided all meals and snacks, and sometimes are under constant surveillance for weeks and sometimes months on end. https://pubmed.ncbi.nlm.nih.gov/39134209/ Obviously such studies are far more invasive and expensive to run than the classic "fill out of a survey" observational study [1], so they tend to be the outliers. But they…

How about just pointing a camera at the bed and fast-forwarding to the few significant events each night?

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

#147

Post by acomms »

LPisGood wrote: post #132
wnorris510 wrote: post #130

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 w…

>and even trained professionals are still off by 40% I find this very hard to believe, unless the term “trained professional” is quite broad. When I was much more into fitness and weighed every meal to the gram, I could tell if a bowl of cereal was a serving to within a gram or two.

I think they're suggesting that the portions you are judging have not been practiced hundreds of times.

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

#148

Post by wnorris510 »

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…

Depends what your goal is. My suggestion is if your goal is weight loss, don't think about calorie tracking at all.

Count your servings of whole vegetables/fruit. Try to MAXIMIZE these. Yes, maximize in order to lose weight.

It's far easier to track just this small subset of food. If you are maximizing these items, you'll naturally start feeling full and eat less sweets. Try to do this slowly over time, changing your diet dramatically overnight will cause you to hate the process and give up.

Change your diet less than 10% per week, keep eating all of your favorite guilty pleasure foods, just incorporate more healthy foods you enjoy as well, ideally before you eat the less healthy items to give yourself time to start feeling full from them. Slowly find more dishes heavy in vegetables that you like. Try to eat them more often. If you're cooking for yourself or serving yourself, try to increase the ratio of vegetable to other items.

Getting pizza? Maybe do a side salad first or a get a veggie pizza. Don't try to cut the pizza entirely until you're further along in your journey.

Don't stress about it. If you're consistently finding ways to make small changes like this you'll start heading in the right direction over the long haul and your pallet will adapt to enjoy the foods you're not used to slowly.

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

#149

Post by f1shy »

bluGill wrote: post #103
chikere232 wrote: post #68

Earlier quoted context omitted.

So what you're saying there's a great business opportunity in people paying to get locked in a diet-cell?

Maybe, though I suspect there are probably a lot of laws around what you can and cannot do so better get several good lawyers to check what the laws really are around this. Drug treatment programs often work like this so that is the first place to look for laws to watch out for. I've heard of other attempts at things like this. Generally you are not locked into a cell, you are removed to a very remote location by bus…

But even if the people will be confined, you have to be careful to take a broad enough population. I can expect people willing to participate in such study maybe are already orthorexic diet freaks? Or very poor people (which have a diet deviated from “mean”)

Doing studies with humans ist just hard!

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

#150

Post by [deleted] »

BoxFour wrote: post #58
liveoneggs wrote: post #49

Earlier quoted context omitted.

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…

> "morning coffee" could be anything from plain espresso shot to full 600+ calorie starbucks "coffee" but the meta-study-machine will lump them together. You're inadvertently proving my point, though. If morning caffeine is correlated with longevity, regardless of the vehicle/extra sugar/etc and controlling for the easy usual circumstances like income, that's pretty useful information!

[deleted]
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