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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

#361

Post by pc2g4d »

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 live by myself and "charge" calories to an account whenever I buy raw foods at the store or eat out. Then, whatever is in my house, I have already "accounted" for in my caloric budget. The strategy comes in figuring out what foods / combinations of foods leave me feeling satisfied. Beans (another great living-alone food, haha) are an allstar. I weigh ingredients for a lot of cooking only so I pace the consumption of rice, beans, etc.

The error in estimation of foods eaten out I treat as a constant factor baked into the daily caloric budget. If I'm gaining weight, the budget just needs to be tightened, i.e. rescaled to account for an error factor that was larger than anticipated. The problem basically becomes estimating one's own estimation error, then adjusting.

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

#362

Post by tart-lemonade »

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…

The margins the FDA allows for class 2 and third group nutrients are also quite generous. I'm sure they made sense back when they were first introduced, but as food science has improved, the standards have not.

> The Food and Drug Administration (FDA) allows calorie content to exceed label calories by up to 20%

https://pmc.ncbi.nlm.nih.gov/articles/PMC3605747/

> Class I nutrients are those added in fortified or fabricated foods. These nutrients are vitamins, minerals, protein, dietary fiber, or potassium. Class I nutrients must be present at 100% or more of the value declared on the label

> Class II nutrients are vitamins, minerals, protein, total carbohydrate, dietary fiber, other carbohydrate, polyunsaturated and monounsaturated fat, or potassium that occur naturally in a food product. Class II nutrients must be present at 80% or more of the value declared on the label.

> The Third Group nutrients include calories, sugars, total fat, saturated fat, cholesterol, and sodium. [...] For foods with label declarations of Third Group nutrients, the ratio between the amount obtained by laboratory analysis and the amount declared on the product label in the Nutrition Facts panel must be 120% or less, i.e., the label is considered to be out of compliance if the nutrient content of a composite of the product is greater than 20% above the value declared on the label.

https://www.fda.gov/regulatory-information/search-fda-guidan...

Edit: Expanded the quotes to include definitions.

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

#363

Post by pixl97 »

saulpw wrote: post #233
wnorris510 wrote: post #225

Earlier quoted context omitted.

You really don't want to pay a one-time fee, it incentives the developers to stop maintaining the app.

This would often be a feature.

Except most app stores require future maintenance and compliance to keep publishing the app. Someone has to keep the lights on.

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

#364

Post by bluGill »

BobaFloutist wrote: post #332
foxyv wrote: post #240

Earlier quoted context omitted.

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…

My favorite example is that cooking spray advertises 0g of fat, giving a serving size of 0.33 seconds of spray

That might even be realistic if you are spraying a baking sheet - since you cover the whole thing. But if you are cooking pancakes and spray the pan after each one you get a lot of carbs.

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

#365

Post by krferriter »

BobaFloutist wrote: post #332
foxyv wrote: post #240

Earlier quoted context omitted.

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…

My favorite example is that cooking spray advertises 0g of fat, giving a serving size of 0.33 seconds of spray

I think this is one of the crazier ones. It's just canola oil! It's the same as spreading that much canola oil on the surface, the spray is mainly convenient because it spreads it out evenly for you without you needing to contact the surface. But Pam gets to put "0g fat" and "For Fat Free Cooking" on the side of all their cans.

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

#366

Post by porphyra »

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…

As someone who takes a photo of every single meal I eat, I was very excited to try out Snapcalorie but it was completely wrong for all the pictures I tried giving it. I uploaded a picture of a recent meal of tomato egg, baked octopus tentacles, and shrimp, and it identified it as pasta, mushrooms, and chicken. Also, it doesn't work for typical home meals that are eaten family-style.

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

#367

Post by TypingOutBugs »

porphyra wrote: post #360
TypingOutBugs wrote: post #6

I try calorie count with My Fitness Pal and holy shit it’s a lot of effort. Eat out and you’re screwed (estimated at best). When you include sauces and oils etc it’s really hard to be accurate in the best of times, and it’s just a pain to keep on top of. Best option is to avoid any so you don’t have to count. I imagine almost everyone will add bad data in a study at some point with the best of intentions.

These apps also lack stuff besides common American/European dishes. Most of my food is healthy homemade food and entering them is an absolute pain. Eating homemade stir fried celtuce [1]? Homemade steamed marble goby [2]? Nope, out of luck. They only have nutrition info for packaged mac and cheese. [1] https://en.wikipedia.org/wiki/Celtuce [2] https://en.wikipedia.org/wiki/Oxyeleotris_marmorata

Interesting and valid issue! I assume it's crowdsourced data from a community and just isn't that popular where you are, but good points.

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

#368

Post by throwway120385 »

steveBK123 wrote: post #349
UomoNeroNero wrote: post #337

Earlier quoted context omitted.

Things are changing nonetheless. My wife is celiac (we’re quite a problematic family: I’m diabetic, she’s celiac), but by law, she is guaranteed that a suitable menu must be available wherever she goes, or at least that waitstaff and business owners know how to handle the situation when she informs them. (I know for a fact that managing celiac disease and the most severe and dangerous intolerances is a mandatory requ…

I think in the US, it's basically an intractable problem the way restaurants operate and are staffed. Low margin, high failure rate businesses with many fly by night small operators. Front of house staff is high turnover, while back of house staff is largely non-English speaking of sometimes questionable immigration/work permit status. And then there is the supply chain since most restaurants are not cooking every si…

Why would you run a bakery and not make donuts yourself? They're dead simple if you have a fryer.

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

#369

Post by Jarmsy »

not2b wrote: post #344
Jarmsy wrote: post #339

Earlier quoted context omitted.

Also when figuring out how much insulin is needed for a given amount of carbs you need to factor in the type of carbs, your individual response to that type of carbs, what fats/protein/fiber you eat with it (fats and fiber tend to slow down the BG rise from carbs, protein can cause a rise when eaten on its own but can also slow down the rise from carbs), what time of day it is (I need around double the amount of insu…

For my wife (type 1 diabetic), physical activity is the big one that throws off her calculations as a walk in a hilly area makes her blood sugar drop like a rock. Of course she always has something with sugar with her but then she has to figure out how much to consume.

Hill walks are particularly challenging for me too. I can do rowing or weightlifting with my sugars staying fairly stable or rising if it's really intense, but something about walking steadily up a gentle slope makes it drop massively. There was some interesting research a couple of years back on how exercising the calf muscle is particularly effective at lowering BG, perhaps that has something to do with it https://pmc.ncbi.nlm.nih.gov/articles/PMC9404652/

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

#370

Post by porphyra »

TypingOutBugs wrote: post #367
porphyra wrote: post #360

Earlier quoted context omitted.

These apps also lack stuff besides common American/European dishes. Most of my food is healthy homemade food and entering them is an absolute pain. Eating homemade stir fried celtuce [1]? Homemade steamed marble goby [2]? Nope, out of luck. They only have nutrition info for packaged mac and cheese. [1] https://en.wikipedia.org/wiki/Celtuce [2] https://en.wikipedia.org/wiki/Oxyeleotris_marmorata

Interesting and valid issue! I assume it's crowdsourced data from a community and just isn't that popular where you are, but good points.

I'm living in San Jose, California, where MyFitnessPal is quite popular --- but being an Asian person I eat a lot of Asian food.
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