You Can’t Trust What You Read About Nutrition

Re:You Can’t Trust What You Read About Nutrition by JohnJamesRambo on Sunday April 23, 2017 @10:06AM (#14178198)

When I worked in a nutrition department it was common knowledge that people are awful at recalling and reporting what they eat. Obese post-menepousal women in the study would, with a straight face, tell you that all they ate that day was a half cup of green beans. You'd look at their food records and it was physically impossible for them to be alive much less obese on the food they reported they ate. Humans are not only awful at reporting what they ate, they have difficulties even seeing it through the distortions of what they want to see. These are the difficulties associated with nutrition research and one of the reasons why there is so much confusion about what we should eat.

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Re:You Can’t Trust What You Read About Nutrition by keithpeter on Sunday April 23, 2017 @06:21PM (#14180743)

My thinking was that by, say, taking a phone snap of your plate at each meal (some chap in the UK did this a few years ago to convince himself to eat less/better) you could produce a more objective record.

Challenge: can you calculate approximate calorific values from images of food on a plate?

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Re:You Can’t Trust What You Read About Nutrition by dpatrick86 on Sunday April 23, 2017 @06:51PM (#14180878)

Interestingly, this has been the approach of a dietary study being conducted by a group doing research on a circadian-focused pattern of eating. The study uses a mobile app as part of their distributed clinical trial design. Participants take pictures of their food with only the option of further journaling. Kind of cool.

Here's the website for the trial (& app)...

http://www.mycircadianclock.org/

Here's a video of the principal investigator (Satchin Panda) talking about his research...

https://www.youtube.com/watch?v=-R-eqJDQ2nU

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Re:You Can’t Trust What You Read About Nutrition by adrianmonk on Sunday April 23, 2017 @09:37PM (#14181410)

Dissolved sugar is probably invisible or close. Can you see a difference between a glass of Coke and a glass of Diet Coke? One has 140 calories and the other has nominally zero.

That's not to say you couldn't approximate it and tell someone they ate a Twinkie today which is more fattening than the steamed broccoli they had yesterday. And you could probably help people manage their diet better with an app that could do that. But it's always going to be an approximation with a potential for large error in certain cases.

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Re:You Can’t Trust What You Read About Nutrition by ReverseCold on Monday April 24, 2017 @01:28AM (#14182144)

Recognizing food with ~90% accuracy isn't too hard. Getting calories from that is also easy. I'm currently building this into a food tracking app as a side project, with the hardest part being designing a UI that doesn't suck.

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Re:You Can’t Trust What You Read About Nutrition by gumby on Sunday April 23, 2017 @01:33PM (#14179210)

I certainly think these records are quite dubious, even for innocent reasons.

But FWIW: when I started intermittent fasting I didn't even eat much on my non-fast days. It was part of an OCD phase on life tracking so I fetishistically measured and recorded everything I ate or drank[+]. I was working from home so wouldn't eat outside the house.

And even I didn't believe my myfitnesspal records. Except that since I was only eating what was in the house it was pretty clear that I really had only eaten one egg: there were the other 11 in the box.

But wow, without the OCD attitude I don't think it's possible.

[+] And what a waste of effort. A lot of work, little insight. It wasn't just food (and I changed my diet to things I could more tightly control in terms of macros) but weight and sleep and what I bought and how much I spent...a lot of work for very very little insight.

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Re:You Can’t Trust What You Read About Nutrition by novia on Sunday April 23, 2017 @01:15PM (#14179094)

>Obese post-menepousal women in the study would, with a straight face, tell you that all they ate that day was a half cup of green beans.

Maybe that was true and they were trying to lose weight?

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Re:You Can’t Trust What You Read About Nutrition by JohnJamesRambo on Sunday April 23, 2017 @10:33PM (#14181567)

The food records were done over repeated visits and long periods of time. Weight, body fat analysis by DEXA scanning, etc. was done as well.

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