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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

#61
post #44

Another way to look at it is that tracking what you eat is very difficult. Currently trying to lose a few pounds and doing calorie tracking. Practically carry a scale and a calorie tracking app with me. About once a day there's still some "estimation" involved due to the fact that all the ingredients are mixed together.

Indeed. I also tracked everything I ate for a long time, many years ago. As soon as you eat something made by someone else you're basically guessing.

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

#62

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 mean I eat very close to the same thing every day, so I am perhaps not the best example, but for example:

> - 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

You weigh all this out once, store it as a recipe and just weigh how much sauce you're putting on things. Oils are so high calorie they're basically all the same, and the only other contributor is really if the seed mass is substantial. Log your upper end, and just assume the sauce comes out as that value. Your sauce recipe is hardly going to vary by an enormous amount, just provided you bias it towards the upper end for the purposes of tracking.

EDIT: Also since people have been dropping app links - https://github.com/davidhealey/waistline this is what I use on Android. Libre with nice integrations, works great.

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

#63

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'm not tracking right now, but used to. So I can answer your question with the caveat that yes it is a pain and I stopped doing it. :)

> 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

Yes. The thing is that it also makes you aware of how much everything "costs" you in terms of calories. You become a lot more aware of how big a glug you give of that oil.

> 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 don't understand this part of your question.

> Leftovers nutrients decrease with time

My goal was not to be "accurate", but to lose weight. Overestimating slightly was in fact preferred. So this is not an effect I would have worried about.

> counting how much you take of a meal shared with others, especially when you serves yourself multiple time

You estimate. You know that the whole thing was X so if you eat a quarter of it that is 0.25*X.

> different species/cultivation methods like the rustic small and dense cucumber from your neighbor and the spongy one from the supermarket in January

Cucumber is flavoured water. Whatever is the variability in calories you can probably just ignore it.

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

#64

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…

It depends why you're tracking things, and what level of "everything" you care about.

Starting with pretty much everything can be a good idea for people to get a sense of what's in what foods. How much does an onion typically weigh? What's that actually adding? What's the difference between getting lean and fattier meat? How much oil are you really adding?

After that it's easier to start dropping things - if I'm trying to lose weight I simply do not care precisely how much celery I've added for the sofrito. I do care about the amount of butter, oil, rice, bread, pasta though.

I'm not concerned about getting fat adding paprika, so I'm not weighing spices. Even if I'm trying to track macros that's just not going to be a considerable contributor to anything.

> - 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)

Prep/measure things first.

Last three things that smooth things over for me

1. Meal prep on a different day. I'm not in as much of a rush at night, it's proportionally less time involved measuring something for a larger number of meals/sauces/components.

2. Having measuring spoons and fast scales nearby.

3. Measuring before & after amounts rather than exactly what to add. If I need to add butter to a sauce until it's the right consistency, or flour to a dough, or whatever then weighing as I go is a nightmare. Instead just weigh it before and after and you'll see what you used. This tip works pretty well for oil too.

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

#65

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…

On the first point, you only need to do it once and then you can reuse the information in future (assuming you stick to the same recipe).

For the other points, I think with any kind of data measurement there is a balance between precision and convenience. Trying to consistently track calories is hard enough, trying to track nutrients at the level of precision you are suggesting sounds technically challenging and frankly exhausting. I think a lot of people will take "average" values for a cucumber, an onion, etc. Like others have said, consistency in measurement is probably more important than finding the absolute truth.

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

#66

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 would imagine that having a camera videoing your preparation of ingredients and cooking would give enough data to classify the ingredients and the used volumes. From the video it should be easier to track the weight of everything... and perhaps depending on how the ingredients are used, determine/predict how the macronutrients are altered during the process.

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

#67
post #34

Earlier quoted context omitted.

You are assuming that the underreporting will be uniform. In reality people may be underrporting things they are embarrassed about and maybe even overreporting the opposite. This is a flaw in the data that is much harder to account for.

Why would that be a problem for reporting relative results if everyone is under-reporting things they're embarrassed about and over-reporting the opposite?

Different people are embarrassed by different things. A frat student's probably going to overstate their alcohol consumption, a Morman understate.

People with bigger appetites underestimate their food consumption, people with smaller appetites overstate.

Not to mention the degree of over/under statement will vary wildly. "A big meal" might be 300 calories for somebody with an eating disorder, or 3000+ for somebody on the opposite end of the spectrum.

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

#68
post #22
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…

I have long said there are two kinds of diet studies: those that don't apply to you because you are not confined to a hospital bed or prison cell; and those that conclude despite our best effort we couldn't get people to eat their assigned diet.

So what you're saying there's a great business opportunity in people paying to get locked in a diet-cell?

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

#69

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…

adjusting seasoning/tasting as you go seems like it would complicate matters too, especially if you're in the heat of it and don't have time to stop and weigh that extra pinch of salt etc

Salt has literally zero calories.

Spices and everything else in general have so little in them it doesn't matter. Something like seeds or pepper more so, but you're hardly going to add so many it changes anything.

Which is kind of the point: you look this stuff up once in order to get a sense of what you're actually doing, and quickly realize what is and isn't going to matter overall. If you're really concerned, you start from a fixed mass you'll season from, and then just use that up as you go.

i.e. if you know you'll be adjusting added sugar, then estimate the total amount of sugar you're comfortable putting in the meal up front, and work from that pool. If it's less, great.

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

#70

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…

Counting works for people because it quantifies their food intake. For many people, that's an effective way to overcome a learned idea that portions should be huge, or that feeling hungry has to be addressed immediately, or that feeling "full" has to be constant. It's not perfect, and I don't recommend it to people with an ED history; however, after about a month or 2 of doing it, it can really change how you look at your meals, and snacking in particular. I don't obsess over it.

> - sauces you make yourself?

I don't count them. I keep my sauces simple and use them sparingly. I'm not trying to get down to sub-10% bf.

> - 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 count them raw, or if my tracker has them, count them as cooked. I don't care about them being super accurate.

> - Leftovers nutrients decrease with time

I don't care. The calorie counts are basically just estimates anyway. It's less a science than a mental game to control your ballpark calories in.

> - counting how much you take of a meal shared with others, especially when you serves yourself multiple time

If I'm making the meal, I count for the whole meal, then estimate for the share. See above for rationale (I don't care that much.) If my friend has cooked for me, I don't care at all, and just try to eat a "reasonable" portion.

> - different species/cultivation methods like the rustic small and dense cucumber from your neighbor and the spongy one from the supermarket in January

The differences are probably not going to matter all that much. By weight, a cucumber is a cucumber is a cucumber; I'm not trying to be perfect, just get a general sense of calories.

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