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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

#271

Post by bitwize »

Havoc wrote: post #110

It’s also just really hard unless you live off packaged meals or only eat thing that are isolated. Something like a curry cooked in kitchen and shared among a family is a complete black box as to who got how many calories. Maybe one person got a different ratio of rice to curry. Or this family likes a sweeter type of curry etc

No, you get a food scale and weight every single ingredient before adding it to the meal. As for who got how many calories, weighing of the portions should provide that information given the ingredients and how much of each there is.

Your metabolism is a system. Like any system, data about its inputs and outputs can be gathered if you would but measure it. Make getting accurate portion sizes a part of your daily routine.

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

#272

Post by loeg »

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…

Getting the grams right goes a long way. At the end of the day, you're trying to approximately measure the caloric density per gram, and maybe macros (proportion protein / fat / carbs). You're thinking in way too fine detail for it to be sustainable. Even with a lax approach, it is pretty tedious.

I wouldn't really recommend tracking long-term, but doing it for a week or so just to get a sense of how much you're currently consuming is a good idea.

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

#273

Post by liveoneggs »

augustk wrote: post #107
llm_nerd wrote: post #89

Earlier quoted context omitted.

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…

Prisons seem like good places to make these kind of studies.

New study reveals fad diet increases risk of being stabbed by 73%!

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

#274

Post by yellow_lead »

foxyv wrote: post #240
UomoNeroNero wrote: post #200

Earlier quoted context omitted.

I have been diabetic for 20 years. I have tried every method, app, plan, and tool, including systems falsely marketed as "smart." No method works or delivers decent results except for using a scale and weighing ALL the ingredients. For a diabetic, eating "out" is always a roll of the dice. The "fun" feedback from post-meal blood sugar is always a reminder of how "eyeballing a plate" is utterly useless.

It doesn't help that food manufacturers intentionally make it hard to measure nutrition from most of their foods. They play around with serving sizes to hide carbohydrates making you have to do math just to keep up. Sometimes they will round down on grams of macros after setting the serving size so they can claim it has zero sugar when it does in fact have tons of sugar. Tic-tacs are the worst about this. They claim…

Plus the whole sugar vs. sugar alcohol nonsense, which I still don't completely understand.

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

#275

Post by skirge »

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.

Compare people with vegetarian diet from India (over 1 billion, a good sample!) with European meat eaters, what will be the conclusions? Do effects "average out"? Or people drinking alcohol with millions of muslims? There are some obvious criteria which should be used for example divide people in age, income and cultural groups (my grandfather used to eat and did different things I did, including avoiding doctors, despite living in same country and even same home).

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

#276

Post by magicalhippo »

vidarh wrote: post #249
dnpls wrote: post #131

Earlier quoted context omitted.

This is it. There will always going to be impossibly unpredictable errors even if you measure everything perfectly. The point of measuring is to be * as accurate as possible *, not 100% error-free. It helps to better estimate portion sizes, calorie / macro amounts. This is enough precision to control weight gain / loss correctly. A lot of people also get their maintenance calories estimation wrong, so it doesn't matt…

A lot of people mess up more by doing a maintenance calorie estimation wrong and relying on it rather than counting calories coupled with weighing themselves and adjusting calorie intake up/down depending on whether they lose/add weight... If you use a feedback loop, then indeed it doesn't matter if your calorie estimate is anywhere near correct anyway, as long as you're reasonably consistent and the errors aren't to…

I did this. I targeted 0.5kg loss per week, and since 1kg of fat is 7000 kcal that meant 500 kcal deficit per week was needed.

I measured my weight every morning (after peeing) and wrote it down, and used it to compute weekly average.

I did weigh ingredients for the first couple of weeks to get an idea, but after that just did rough estimates coupled with tuning based on feedback from the body weight every week.

Had a near perfect linear trend for the year I did this.

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

#277

Post by kjkjadksj »

jeltz wrote: post #248
ellisv wrote: post #242

Earlier quoted context omitted.

I'm a big fan of European serving sizes compared to U.S. for food – but when it comes to beverages, particularly water, I can't believe how much they charge you for how little they give. I understand everything comes in bottles with VAT but even asking for tap water I found they'd only bring a very small glass.

In some European countries water is free. I am from Sweden where all places have free tap water and fancy places often have free sparkling water.

Along the mediterranian seemed like the only place to get free water were the ancient fountains that spittle out a stream. But then you’d have to wait for the inevitable old man to finish washing his head and arm pits in that fountain. Beer was usually substantially cheaper than the water offerings.

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

#278

Post by colechristensen »

derbOac wrote: post #140
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…

It's really hard (emotionally or motivationally) to undereat, which is what you need to do consistently for a long time to lose weight. Aside from the hunger issue, food is enmeshed in all sorts of value having nothing to do with nutritional value per se and everything to do with sociopsychological value. I think I've massively underestimated that in my own life, or misunderstood what that meant or something. I think…

Also there are ways to convince your body that it needs less, and the journey from A to B is very uncomfortable. If you do it wrong you will just endlessly be suffering from your body thinking it's starving.

On top of that though is you have to get over your intellectual ideas of how much food you think you need to eat.

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

#279

Post by barbazoo »

UomoNeroNero wrote: post #200
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…

I have been diabetic for 20 years. I have tried every method, app, plan, and tool, including systems falsely marketed as "smart." No method works or delivers decent results except for using a scale and weighing ALL the ingredients. For a diabetic, eating "out" is always a roll of the dice. The "fun" feedback from post-meal blood sugar is always a reminder of how "eyeballing a plate" is utterly useless.

That sounds really hard. Is the purpose of determining the amount of food so you can adjust the amount of insulin? Sorry, I don't know about the day to day of living with diabetes.

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

#280

Post by kjkjadksj »

zahlman wrote: post #187
zeroonetwothree wrote: post #155

Earlier quoted context omitted.

I don’t see why it would be bad to get more water to drink

There's actually something of a stereotype that Japanese places will give you unreasonably small portions of water with meals. (Dogen plays off this in some of his videos.) But then, I think it's only been Americans I heard this from, so.

The free water cup in a lot of places in the US is like a 6oz slosh now.
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