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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

#201

Post by bluGill »

DannyBee wrote: post #83

"> Is coffee good for you? What about wine or chocolate? Scientists trying to answer these questions" These are dumb questions to ask in the first place, because the "you" and "good" here are too personal for any general answer to be useful to most people. Unfortunately, this is not just lazy writing that took complex questions and simplified them to the point of uselessness - we really are asking these kinds of ques…

It is an important question because people want to think whatever their vice is, it is good for them. Thus you can make lots of money if you can get a headline showing something is good, no matter how bad the study is.

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

#202

Post by cainxinth »

In my experience, people are especially bad at understanding how calorific alcohol is. Carbs and protein are generally 4 calories per gram. Alcohol is 7 calories per gram. Only fat is more energy dense at 9 calories per gram.

I can recall in the aughts when there was a major low carb food trend and Bacardi had a popular ad campaign around the fact that their rum had no carbs, basically marketing it as the smarter option for people watching their weight -- even though all unflavored hard liquor has no carbs and is still incredibly calorific.

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

#203

Post by m_ke »

felideon wrote: post #192
m_ke wrote: post #139

Earlier quoted context omitted.

At Bitesnap we were surprised at how much interest there was from researchers to use our app for diet tracking. It turns out giving people a piece of paper to write “grilled cheese sandwich for lunch” is not a scalable and reliable way to collect research quality data. We even worked with USDA on putting together a food logging dataset: https://agdatacommons.nal.usda.gov/articles/dataset/SNAPMe_A...

What happened to your app? I was on such a research team (Scripps) that used your app for the study (PROGRESS).

Unfortunately it was shut down after I sold the company to MyFitnessPal.

I was a shitty business person who thought it made sense to try and build a free consumer product on a bootstrapped budget. We had some traction on the B2B side that paid the bills but COVID took a dent in it and it would have taken a long time to build back the revenue stream selling to healthcare companies (tip for others, it can take 6-18months to close healthcare deals and another 6-18months to integrate)

We had a few offers to sell the company and took the one that seemed to make the most sense.

If there’s anything I can do to help out my email is michalwols at the Google email provider domain

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

#204

Post by disgruntledphd2 »

tejohnso wrote: post #177
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…

> you need to use a food scale or something that measure the volume of food Isn't that obvious? Basic high school science projects would have students using measuring devices. Are you saying that it's common for nutritional studies to tell people to eyeball their portions and that is then used as actual data? I see from the article "Nutritional epidemiology studies typically ask people to keep a food diary or complet…

Yup, I discovered this 14 years ago and wrote a proposal to do barcode scanning to help, but left academia soon after.

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

#205

Post by aqme28 »

cainxinth wrote: post #202

In my experience, people are especially bad at understanding how calorific alcohol is. Carbs and protein are generally 4 calories per gram. Alcohol is 7 calories per gram. Only fat is more energy dense at 9 calories per gram. I can recall in the aughts when there was a major low carb food trend and Bacardi had a popular ad campaign around the fact that their rum had no carbs, basically marketing it as the smarter opt…

It's why you don't really see any beer below like 90-100 Calories, despite all the "low calorie" beer marketing there is out there.

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

#206

Post by zahlman »

ebiester wrote: post #57
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 am very diligent, and the truth is that it is hard and it changes how you eat to be more countable. On a cut, it matters more. On maintenance, it matters less. But most of it is a guessing game and making an assumption that it will all even out later. Ignore spices - you can assume 25 calories a day and it’ll still be too much. Be diligent about oils. 9 calories a gram bites you quickly. But ultimately, if you miss…

>But ultimately, if you miss 100 calories a day, and are in a 500 calorie deficit recorded, you are still going to lose .8 pounds a week. And if that is consistent, adjust your portions and be fine with how you record.

And the thing is, you'll need to do this anyway - because you can't be sure in advance how many calories represents a "500 calorie deficit" for you, in your specific current conditions.

I was quite underweight in my youth, but I successfully reversed these kinds of feedback techniques to gain weight, and currently maintain what seems to be a healthy level. John Walker (co-founder of Autodesk, who passed away early last year) wrote The Hacker's Diet describing the basic technique. It's still live at https://www.fourmilab.ch/hackdiet/ .

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

#207

Post by leoc »

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…

I suspect (I'm not an expert) that for subjects like nutrition, experimental psychology and so on the next big step forward isn't scientific but political: figuring out how to somehow get funders, researchers and others lined up behind a Big Science model where a very few organisations run experiments with those truly large participation numbers. There are obvious risks in switching to such a model, but if small or middling experiments simply can't answer the open questions then there may be no better alternative.

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

#208

Post by dkarl »

aziaziazi wrote: post #171
iwanttocomment wrote: post #119

Earlier quoted context omitted.

As someone who has successfully tracked calories in the past with great effort, the trick is to be strict about measuring calorie-dense foods, but to be liberal with "lighter" foods where the calories are functionally de minimis. An ounce of olive oil has 250 kilocalories. An ounce of lean protein generally has 30-50 kilocalories. An ounce of green vegetables contains virtually no kilocalories. As such, things like o…

That may sense. Most of the folks here seems to track calories and other macro. In the meantime... > micronutrients like vitamins are not functionally possible to be measured ... my concern is micro : I'm engaging on a full vegetable diet (+shrooms +minerals!) and am concerned about thinks like iron, selenium, calcium... I (got-used-to) love vegetable and eat a lot of them so I'm probably fine with most micros, howev…

Both supplementation and dietary strictness are scary because of the consistency. A quantity that is safe every day for a week or a month is not necessary safe every day for a year, and a quantity that is safe for a year is not necessarily safe for ten years. I've known two long-term vegetarians who were diagnosed with iron deficiency anemia in their thirties. One of them passed out while cycling home from work, which I'm guessing meant that she was suffering in small ways for a long time before she realized it. But if she took a mineral supplement every day for twenty years, how might she find out if she was getting too much of something? They sell the same supplements to people who are 5' 100 lbs and 6'4" 250 lbs.

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

#209

Post by taeric »

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.

Ha! I hadn't heard of this before, so it caught me completely off guard.

The coffee was the one that really surprised me. Order a coffee and get a 6-8oz cup. With nothing on the menu to indicate you can get a 12-16oz. Was surprising. (Not bad, mind. Just surprising.)

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

#210

Post by screye »

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 track everything. (with caveats below)

It's less important to get the calorie numbers perfect, and more important to be consistent in your under/over reporting. To me, it's a tool to track the consistency of my diet. No amount of over/under reporting is hiding 2 slices of pizza on a graph.

In sweet dishes, 2 TBSP sugar is 120 calories. In savory dishes, 1 TBSP oil is 100 calories. None of the other minor ingredients have any appreciable calories. You should be able to predict quantities within a 1 TBSP tolerance range. The rest of your calories come from foods with visible volume, and chatgpt does a good job of predicting their calories from screenshots. With that, hopefully, you don't under-report any meal by more than 200 calories. If you're following a recipe, dump the whole thing into chatgpt, voila.

Over 2 meals, under-reporting by 200 calories feels like a lot. But wait to have 1 milkshake, beer or 1 tiny baklava and see the graph shoot beyond any of these pesky concerns. The goal is to track and be accountable for the latter: the ultra-palatable foods. The extra onions and parsley are not making you fat.

For outside food, you can find official numbers reported by fast food places. Add 20% to their estimate. Actually, add 10% to all estimates. Every your own food. If a full meal randomly lands under 500 calories. I look at it with scrutiny. It takes careful effort to stay under 500 and feel full. If it happens consistently and you don't lose weight, then you're tracking something wrong.

PSA: NUTS HAVE A SH*T TON OF CALORIES. ALWAYS REPORT THEM. YOU WILL BE SHOCKED. _____

The system has worked quite well for me.

In all cases, my weight gain has corresponded to long periods of door dashing, liquid calories & dessert binges. On these days, my daily calorie consumption jumps by ~800 calories. Getting your oil intake wrong by 1 TBSP makes no difference to that number. Focus on the main culprits.

____

P.S: ofc, if you care about micros, my comment is irrelevant.

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