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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

#461

Post by rolisz »

Sohcahtoa82 wrote: post #448
rolisz wrote: post #427

Earlier quoted context omitted.

How much protein were you getting on the high protein diet? For a long time I heard about "get lots of protein, it helps with satiety" and I thought I had enough protein. When I went to a nutritionist and she made me do a food journal, her first feedback was that I needed to up the proteins even more. And then indeed, I stopped feeling as hungry.

Typically 100-150g per day.

Try 1g/pound of bodyweight (some say ideal bodyweight). For me it's 180-190 g per day. It's hard to eat that much protein. But when I do, the hunger goes away (unusual feeling for me too)

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

#462

Post by agos »

nemomarx wrote: post #145
agos wrote: post #118

Earlier quoted context omitted.

> 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 re…

I get what you're saying, but I'm referring strictly to the task of nutrient tracking. I'm doing it right now while _not_ trying to lose weight (or gain it, or necessarily stay the same weight) and it's a big game of eyeballing stuff where it's incredibly hard to get it right

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

#463

Post by xandrius »

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…

Fats are definitely the easiest way to mess up counting, especially when a lot of people can't compute not cooking without oil/butter.

If the goal is losing weight, I found that maximising volume (e.g. Minimising calory density) works wonders for me. I am used to being full before feeling satiated (mostly upbringing I guess), so this is my trick.

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

#464

Post by wrfrmers »

3vidence wrote: post #421
Pigalowda wrote: post #375

Earlier quoted context omitted.

What happens if I ingest 0 calories for 3 months?

To parents point your metabolism will drastically change over those 3 months and the rate at which you lose weight will change. Additionally the distribution of your muscles and fat will also change.

I don't know the mechanics, but my understanding is that such a water fast also permanently alters your digestion and metabolism.

A (logical extreme) example I was thinking of counterig with: if you eat 500,000 calories in 24 hours on the first of the year, and nothing else for the rest of it, you'll achieve a 1,350 calorie/day average, certainly enough to lose a significant amount of weight. And you will! Because your stomach will have ruptured and you'll be dead by the 2nd. Rotting is one way to burn calories. (I mention this to illustrate how focusing solely on the numbers, to the detriment of the actual lived quality of life during the weight management process, misses the forest for the trees.)

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

#465

Post by tomrod »

3vidence wrote: post #423
tomrod wrote: post #133

Earlier quoted context omitted.

Actually, this is why stats exists in the first place. Larger samples (including metastudies) are so powerful -- you can measure and predict causal impact of test factors even if you can't control for unobservables. The goal is to minimize type 1 and type 2 error. So long as those unobservables are not driving a selection bias, you get wonderful things like the central limit theorem coming to the rescue. No one can m…

This somewhat feels like 2 layer neural networks are a universal predictor. It is true in the limit but not useful in practice. When it comes to studying food / diet studies really do need to be a lot more careful about trying to control their variables. Nutrition science as a field seems to have few absolute truths and many many overturned papers / results.

Central limit theorem is, without qualification, useful in practice.

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

#466

Post by ryan-richt »

Full_Clark wrote: post #413
ryan-richt wrote: post #268

Earlier quoted context omitted.

There is actually an elegant _mathematical_ solution to this problem using sensor fusion and a differential equation model of the science: if you weigh your food almost all of the time at home, and only make portion and ingredient guesses when infrequently eating out, we can actually estimate your personal rate of underestimation and correct for it. Our startup (BODYSIM.com) has also been doing research on this a lon…

How reliable do you find the calories-burned data from fitness trackers to be? Are there any brands that have higher accuracy than others? Are there any hardware features like pulse monitoring that improve the accuracy? I find that the raw step count varies up to 66% between my phone and my wrist-worn tracker and I can't close that gap just by making sure my phone is never left behind.

Not great! We have to "correct" them mathematically. Some can be crazy off until you calibrate them, for instance my husband's then-new Apple Watch was 2X off for months until he transitioned from winter indoor treadmill running to an outdoor run where it can calibrate. But even Garmin/Whoop/Oura can be substantially off, 50% easy. A "fun" simple way you can test yourself: do the exact same weight lifting workout but at + or - 10ºF between the two replicates. Guarantee you'll get dramatically different "calories burned" when in reality they are more similar. Your heart beating faster to cool you off in the hotter environment even though you're doing the same amount of (physics definition) "work" is NOT burning 50% more calories. Heart Rate is just a proxy for "work" and is confounded with other causes of heart rate change, such as ambient temperature/cooling.

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

#467

Post by ryan-richt »

nathancahill wrote: post #287
ryan-richt wrote: post #268

Earlier quoted context omitted.

There is actually an elegant _mathematical_ solution to this problem using sensor fusion and a differential equation model of the science: if you weigh your food almost all of the time at home, and only make portion and ingredient guesses when infrequently eating out, we can actually estimate your personal rate of underestimation and correct for it. Our startup (BODYSIM.com) has also been doing research on this a lon…

This is really interesting, and I'll probably sign up for your app (I'm training for rock climbing). I've used a kitchen scale for a few weeks at home and got pretty good at estimating portion size during that time. Biggest takeaway was that even if you aren't "over-indulging" when you eat out, the portion sizes (especially in the US, less so in Europe) are just insane. 2-3x portions. Ordering half-orders or starters…

we'd love to have you! LMK any questions over email or whatnot.

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

#470

Post by username135 »

bluGill wrote: post #442
username135 wrote: post #419

Earlier quoted context omitted.

Alt tip: dont use any fat on the pan when cooking pancakes. Gives the surface that restaurant quaility, smooth evenness.

Depends on the pan and pancake. Restaurants use a fair amount of fat in their dough so fat on the griddle isn't needed, if you make your own batter (as opposed to store bought) you can control this and reduce the fat such that you need to add some to the pan. The pancakes will of course taste different. In my case I'm making sourdough on cast iron - I've never figured out the trick to make the first couple not stick…

True!
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