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How do food manufacturers calculate the calorie count of packaged foods? (2003)

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Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#21

Post by loxs »

jcfrei wrote: post #13

I have a related question: Can the calorie count reliably predict the effect on a persons weight? Or is the amount of carbohydrates and fats much more important?

No, because different people have different metabolism. Think of it as if the body has a "target" weight. It actively tries to reach that weight and can compensate overeating (easily, by throwing away excess food) and undereating (not as easily but still can compensate a lot). This mechanism interferes heavily with your diet and that's the reason you can't easily change your weight at will by changing your diet. It changes over time if you permanently change your diet and lifestyle, but takes years.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#22

Post by alexbock »

chris_va wrote: post #18
alexbock wrote: post #14

Earlier quoted context omitted.

You would have to be very confident in the accuracy of your measurements to throw away your margin of error like that. If you report values 13% lower to try to appeal to consumers and your lab numbers are off by 3%, now you're wrong by over 15% and you're going to have a problem (if anyone even notices, or cares). Are there any Polish media reports about this practice? It sounds like the kind of thing the American me…

Kind of reminds me of this story: http://www.informatics.indiana.edu/donbyrd/Teach/Math//Gamow...

Would it be possible for the baker to distribute bread to customers in such a way that the weight appears to follow a fair curve for any one customer, but is still unfair if all loaves for all customers were analyzed in aggregate? (something like Simpson's paradox?)

After the professor first discovered him he obviously could have started giving him loaves calculated to follow the fair distribution, but I'm not sure if it's possible to scale that technique.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#23

Post by thesimon »

lukasm wrote: post #12

In Poland it's regulated, you can be off by 15%. My mate did tests in a lab. All products he picked showed 15% lower kcal value on the packaging. I pick reduced fat houmous from the fridge. The label says 100g has 256kcal (18g of fat, 13g of carbs, 8,5g of protein = 248kcal)

And apparently in the US you can be off by whatever you want

https://www.youtube.com/watch?v=hE2lna5Wxuo

The video also deals with calorie count in restaurants. The NYC regulation to require calorie counts directly on the menu really seems like a good idea. Other than the people already knowing the rough calorie count, who checks the obscure and difficult tables on the website?

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#24

Post by maxerickson »

alexbock wrote: post #22
chris_va wrote: post #18

Earlier quoted context omitted.

Kind of reminds me of this story: http://www.informatics.indiana.edu/donbyrd/Teach/Math//Gamow...

Would it be possible for the baker to distribute bread to customers in such a way that the weight appears to follow a fair curve for any one customer, but is still unfair if all loaves for all customers were analyzed in aggregate? (something like Simpson's paradox?) After the professor first discovered him he obviously could have started giving him loaves calculated to follow the fair distribution, but I'm not sure i…

If he is able to control the loaf the professor gets he could buy 1 correct form.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#25

Post by ng12 »

ourmandave wrote: post #15

Depends on what side of the package you're reading. On the back label its says calories per serving. On the front they use a different serving size to make it seem like it's low-cal. Like popcorn that's 140 cals/serving, but on the front it says 35 cals per cup . http://www.foodfacts.com/ci/nutritionfacts/snack-foods/smart... Or a pkg of 2 cupcakes is 380 cals, but they'll say 190 cals per cake (in small type). It ma…

But they also list servings per package. As someone who relies on this information out of medical necessity I've never felt it to be that confusing.

The EU/UK, on the other hand, makes it incredibly difficult by listing things in units of 100g. Nothing like sitting in a dark movie theater trying to calculate fractions.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#26

Post by misinformation »

chris_va wrote: post #19
jcfrei wrote: post #13

I have a related question: Can the calorie count reliably predict the effect on a persons weight? Or is the amount of carbohydrates and fats much more important?

Reliably? Short version is no, and it is even more complicated. Two individuals eating the same food will gain weight differently, depending on a large number of factors.

Bit different answer: Yes it is possible. While it is true that two individuals eating the same food will gain weight differently, if you count your calories and measure everything you'll eventually learn (In the body building community we usually say two weeks) how many calories you need to keep your weight. With that information, you can adjust your calorie intake to lose weight. Say your maintenance is 2500 calories, then by eating 2000 instead, you'll lose 1 pound a week.

Keywords if you want to look it up more: TDEE, 1 pound = 3500 calories, calorie in calorie out

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#27

Post by tezza »

> 9 Kcal/g for fat. [...] These numbers were originally determined by burning

This method for calculating the calorie count for fat has in my opinion allowed the demonisation of fat.

Our stomachs are imperfect at digesting globules of fat. Burning-until-gone releases much more of the energy than surface acting acids and proteinases.

Effective calorie count for fat just has to be so much lower than the listed value.

Constrast that with sugars, where the absorbtion mechanism is crystaline dissolution. Disolving crystals is an almost perfect 1-1 process

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#28

Post by misinformation »

loxs wrote: post #21
jcfrei wrote: post #13

I have a related question: Can the calorie count reliably predict the effect on a persons weight? Or is the amount of carbohydrates and fats much more important?

No, because different people have different metabolism. Think of it as if the body has a "target" weight. It actively tries to reach that weight and can compensate overeating (easily, by throwing away excess food) and undereating (not as easily but still can compensate a lot). This mechanism interferes heavily with your diet and that's the reason you can't easily change your weight at will by changing your diet. It c…

The body is homoeostatic and will try to repel any change in body composition and weight. While it is also correct that different people have different metabolism and gut flora that affects our calorie conversion from different foods, the answer is yes. If you count your calories reliably, you can reliably lose weight by adjusting your calorie intake to match your body. If you throw out your body's own function of regulating its weight by measuring your food, you can accurately predict what you'll weigh in, for example, five months. It does not take years.

Noteworthy however is that with change to body composition, your TDEE (known as the amount of calories your body needs to maintain its current weight) changes. However it can easily be accounted for when losing (or gaining as may be the desired outcome for some people) in a controlled way.

Regarding the different metabolism thing: https://examine.com/faq/does-metabolism-vary-between-two-peo... (To asnwer the link's question: Yes. 600 at most calories if you compare two outliers.

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#29

Post by [deleted] »

ng12 wrote: post #25
ourmandave wrote: post #15

Depends on what side of the package you're reading. On the back label its says calories per serving. On the front they use a different serving size to make it seem like it's low-cal. Like popcorn that's 140 cals/serving, but on the front it says 35 cals per cup . http://www.foodfacts.com/ci/nutritionfacts/snack-foods/smart... Or a pkg of 2 cupcakes is 380 cals, but they'll say 190 cals per cake (in small type). It ma…

But they also list servings per package. As someone who relies on this information out of medical necessity I've never felt it to be that confusing. The EU/UK, on the other hand, makes it incredibly difficult by listing things in units of 100g. Nothing like sitting in a dark movie theater trying to calculate fractions.

[deleted]

Re: How do food manufacturers calculate the calorie count of packaged foods? (2003)

#30

Post by misinformation »

jcfrei wrote: post #13

I have a related question: Can the calorie count reliably predict the effect on a persons weight? Or is the amount of carbohydrates and fats much more important?

To directly answer your question: if you want to use a heuristic for losing weight, it should not be to count just carbohydrates or just fats or both together -- but your total calorie intake.
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