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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

#311

Post by djtango »

Ekaros wrote: post #94
djtango wrote: post #43

Earlier quoted context omitted.

I'm not convinced calorimetry is particularly useful for any nuanced diet planning. We can't eat wood (or coal) but they're very calorific when measured via bomb calorimetry.

I was thinking of methane as input. But what about it as output? How much does leave the system? And should this not be in calories "out" column, but I don't think that is usually counted there...

Could you elaborate on what you mean? What does methane have to do with this and what is the "out" column?

Calorimetry is just measuring the heat transfer from combustion, usually by measuring the temperature change of a known quantity of water in the classical experiment. You perform versions of it in high school and undergrad

Calories are just a unit of energy, and heat can be related back to energy (joules for people using SI)

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

#312

Post by [deleted] »

mattlondon wrote: post #254
marinmania wrote: post #175

Earlier quoted context omitted.

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 entir…

[deleted]

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

#313

Post by barbazoo »

skyyler wrote: post #290
barbazoo wrote: post #281

Earlier quoted context omitted.

> commercial salad dressing almost always has sugar in it. Look at the nutritional facts label next time you're shopping for it. There's a few brands that offer "simple vinegar and oil" style dressings that don't have any sugar in them, but MOST salad dressings Americans come in contact with are full of sugar. Making salad dressing is really easy btw in case anyone wants to try. Often all you need is olive oil, vineg…

If you have an immersion blender, making mayonnaise without sugar in it is very easy: https://www.seriouseats.com/two-minute-mayonnaise (And it tastes way better than commercial mayo!) I love this author's recipes; it's the opposite of the normal recipe-preamble-slop. All of the stuff before the actual recipe is relevant information. In more complex recipes, he goes over the testing and process that led to the finish…

Awesome, I'll give that a try. What I like about it is that you can use whatever high quality eggs you normally use instead of the cage eggs that mass producers will use. Until now I had to resort to vegan mayo.

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

#314

Post by freedomben »

yellow_lead wrote: post #274
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…

Plus the whole sugar vs. sugar alcohol nonsense, which I still don't completely understand.

IANA nutritionist or expert at all in this area so take this with a grain of salt, but my understanding from looking into it is that the sugar alcohol doesn't break down in digestion and isn't absorbed, that's why the "carbs" from sugar alcohol "don't count."

I would recommend taking it easy on the sugar alcohols even though they "don't count" because they can cause significant gas ;-)

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

#315

Post by Fricken »

The thing is we're all experts at eating food, we've all been doing it our whole lives. You'd think in that time one would have cultivated an intuition about whether they are eating too much or too little regardless of the nutrition information.

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

#316

Post by tombert »

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…

> 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

I can't speak for anyone else, and I actually do try and weigh everything, but if I forget to weigh or the portions are too small to measure with my cheap kitchen scale: I weigh out my serving of the finished product, and Google either the restaurant or premade-grocery-version of what I made and look at their nutrition labels.

Obviously it's not going to be perfect, but I figure that my homemade pizza sauce will have roughly the same ingredients as the Ragu pizza sauce at the grocery store and thus roughly the same calories and nutrition at a per-ounce level. I always assume that my homemade stuff is 20% higher in calories more just to compensate for uncertainty, but doing this I did manage to lose about 60lbs.

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

#317

Post by andrewf »

Izkata wrote: post #96
beezlebroxxxxxx wrote: post #70

Earlier quoted context omitted.

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…

Yep, it doesn't particularly matter if something that's actually 212 or 198 is entered as 200. Sometimes you'll be slightly over, sometimes slightly below - just try to be accurate and these small mistakes average out. Typically I figure out the actual weight/volume once or twice to get a sense of how much it is, then just eyeball it most of the time and go for the same amount as last time I measured.

I worked on calorie counting software in the 00's. We had desktop software that just used floats, meanwhile the Palm Pilot software was all integer math (counting things in 10ths and 100ths when that precision was needed.)

We'd get emails about people seeing 577 calories on the Palm Pilot and 578 calories on the desktop. "None of the numbers are that accurate anyway!" was a sensible answer but not very brand aligned.

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

#318

Post by tombert »

dkarl wrote: post #208
aziaziazi wrote: post #171

Earlier quoted context omitted.

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, whic…

I mean, in regards to iron specifically, I get bloodwork done in my yearly checkup and it will tell me my iron levels.

Historically mine have always been low but in September of 2023 I started a diet and started taking iron supplements, and when I got my bloodwork I was in the happy "green" range.

ETA:

I should point out that I'm a pretty tall dude (~6'5"), which might make it easier for me to avoid getting too much iron, but if I were getting too much iron I assume it would probably show up in my blood tests?

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

#319

Post by moduspol »

bluGill wrote: post #103
chikere232 wrote: post #68

Earlier quoted context omitted.

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

Maybe, though I suspect there are probably a lot of laws around what you can and cannot do so better get several good lawyers to check what the laws really are around this. Drug treatment programs often work like this so that is the first place to look for laws to watch out for. I've heard of other attempts at things like this. Generally you are not locked into a cell, you are removed to a very remote location by bus…

Can't we just use literal prisoners?

That's what I always thought about the kind of research RFK Jr is always talking about. Normally it's not ethical to do food / medicine trials with prisoners, but these would be trials like giving regular food to one set of prisoners and food without dyes or chemicals to the other. The "test group" would just be getting healthier food.

Seems like just radically measuring portion sizes might fit into the same kind of thing. And you could probably measure activity level more easily, too.

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

#320

Post by joseda-hg »

yapyap wrote: post #263
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.

I’m rather unknowledgeable on diabetes, so here’s a question that may seem basic: does choosing healthier meal, a salad instead of sweet ribs, not suffice for a good blood sugar?

Healthier isn't a good metric, A carb heavy salad will probably be worse than those protein heavy ribs by themselves (Maybe the rib sauce will tip you over, or maybe you will use a salad dressing that put any "healthiness" to the test)
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