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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

#251

Post by ttoinou »

JoeAltmaier wrote: post #136

People are bad at reporting ANYTHING. Exercise, food, sex, grooming. Just ask a lawyer or anybody trying to get a story out of somebody. This should be a fundamental understanding of anybody asking people anything. That scientists imagine there's some accurately-reporting population of subjects for their experiment is an example of the breathtaking naivete of scientists.

Yeah the problem seem to be the researchers in the first place here, they're probably in a hurry to produce papers with supposedly real data.

Or maybe the researchers know all this from years working in this field, the problem might be from those simplifying the research for the public

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

#252

Post by mattlondon »

mrgaro wrote: post #176
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 downloaded SnapCalorie to try it out on Android. I went all the way through the sign-up phase, only to discovery that I would need to activate subscription in order to have the 7-day trial. Ended up uninstalling the app :(

Thanks - just read this comment while it was downloading and installing, so uninstalled straight away.

Back to fitness pal and scanning barcodes (which is not really much of a hardship tbh)

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

#253

Post by ttoinou »

shadowtree wrote: post #141

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 pac…

Another more sensible explanation is that the calorie theory is fully wrong and unscientific, despite using numbers and measurements (it sounds very mathy though)

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

#254

Post by mattlondon »

marinmania wrote: post #175
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 highly recommend people get a food scale/measuring cups and weighing everything single thing they eat (even small things like nuts and cooking oil) for at least two weeks. After that I think you have a much better appreciation for how many calories your regular meals and snacks have.

+1

The killer for me was breakfast cereals. The box shows a full bowl of whatever, full to the brim etc. in reality the pictures are probably 5 or 6 or more servings - a single serving would barely even cover the base of the bowl and even then be 200ish calories before milk.

If you just pour yourself "a bowl" of cereal without thinking or weighing then you're probably having 1200+ calories (or about 50% of your entire daily quota) even before you add milk or anything else, just for breakfast.

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

#255

Post by ttoinou »

_dark_matter_ wrote: post #79
FredPret wrote: post #75

We're far too generous with what we allow to be called "science". There is no dietary research, because you can't pull off an unbiased dietary study over a meaningful period of time. Practical and ethical problems abound. Maybe one day we can simulate n=10mm people from the neck down for a period of 30 years, and feed half of them bacon and half of them beans, but even that will have the major problems of being a sim…

There are ALL kinds of things we can't run experiments on. Climate, society, evolution, tech development, surgery, and more. We don't throw our hands in the air and say "science here is impossible!". Instead we roll up our sleeves and develop more and better causal inference models that improve over time.

Maybe we should indeed develop different words and taxonomy to differentiate the methods in different fields. Calling anything a "Science" brings an aura of seriousness, which doesn't necessarily exists, it's a way to manipulate our minds to make us believe it is as rigorous as physics and maths

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

#256

Post by idiot900 »

wnorris510 wrote: post #224
ploynog wrote: post #188

Earlier quoted context omitted.

I think the complaint is that you only get told that you require a paid plan AFTER signing up. At least on a brief look on the Play Store page and your website, it does not immediately mention it prominently. That seems like a very dark pattern and is, honestly, pretty scummy.

This is not a dark pattern, it's just a constraint that the app stores place on the pricing disclosure that is very non-intuitive. You have to mark your app as "free" to download if you charge a recurring subscription fee. You can only mark it as paid if there is a one time fee to download the app. Our FAQ and pricing pages all list that it is a paid only app. All of our ads explain that it's subscription based. Anyo…

https://www.snapcalorie.com/

I cannot find a FAQ or pricing page on your website.

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

#257

Post by ttoinou »

jfbaro wrote: post #78

I was wondering if there’s a way to automatically measure calorie intake—like some kind of biosensor that could be worn on the body. Companies are investigating this I bet!

you don't put energy into your body

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

#258

Post by nemomarx »

bluGill wrote: post #185
everdrive wrote: post #156

Earlier quoted context omitted.

The body can compensate at the margins. Eat 5 fewer calories per day and you will see zero change. Eat 500 fewer calories per day, consistently every day, and you will absolutely see changes. (I'm not actually suggesting that it would be _healthy_ or advisable to drop your diet by 500 calories -- just pointing out that the body cannot compensate indefinitely.)

The compensation is often lower energy levels. Your body compensates by keeping you from doing as much.

yeah, you want to force yourself to do some activities that keep your metabolism up along with the restrictions

you can't exercise out of a bad diet but exercise is a helpful supplement to a good diet too. it's just that making yourself do it when you're tired and hungry is draining.

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

#259

Post by SoftTalker »

Any research or studies based on self-reporting or interviews should be very suspect. Most people will answer or report what they think the researcher wants to hear, or what they think will make them "look good" even if the responses are anonymous.

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

#260

Post by everdrive »

Spivak wrote: post #189
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…

Oh hey, I'm the wife in this story. Having a fixed $/month budget for "things you buy at a grocery store" was doomed from the beginning. All the stuff in your house/pantry are on all kinds of weird replacement cycles that vary with usage and changes in habits. A monthly cadence also makes you sub-optimally plan around price movements. An attainable goal is to reduce the average amount of monthly grocery spend and you…

To your credit, our approach never worked :)

I totally agree that you'd need to find a reasonable average weekly cost because costs and timing would vary. In my mind, this means you could find a reasonable average weekly cost that you often go under, and seldom go over. But, it just never happened for us. In principle we could have just kept raising the price ceiling, but eventually that becomes meaningless in the context of a budget. To me, at least, it felt just like calories; what could have been a pretty easy math problem was defeated by human psychology.

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