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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)

#31

Post by maxerickson »

tezza wrote: post #27

> 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. C…

It's a well understood process:

https://courses.washington.edu/conj/bess/fats/fats.html

Also, you can experience what happens when you don't digest fat by eating a good bit of Olestra.

https://en.wikipedia.org/wiki/Olestra#Side_effects

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

#32

Post by misinformation »

tgb wrote: post #20
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?

I think the answer is that it's really hard to study this, since food diets are hard to control over long periods of times but that current research is consistent with calorie counts being a good estimator of a person weight gain/loss. Here's a reasonable summary with some studies you can look at for the details. [1] But this is certainly an area of ongoing research and the devil is in the details: does it matter whe…

I won't link to any studies but regarding [2] (gut microbiome] does affect it ever so slightly. I'm just stating things from memory now, but I remember reading that our gut bacteria now is different from 50 years ago in such a way that a person eating (for example) 2000 calories then, would now have to eat 2200. Made up numbers, but the effect was between 5-20%.

As for your last question (food composition and satiety), tangentially related, in the literature regarding this it seems as if keto has a lot of support for weight loss. Not because of the way it affects your metabolism or gut bacteria, but because it does satiate people more adequately than other diets it was tested against (regular western, Scandinavian and paleo).

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

#34

Post by maxerickson »

silviogutierrez wrote: post #3

There are foods on which the standard processes don't accurately measure energy content. Or at least, certain manufacturers tell us that. Not sure if to believe them or not. Example: Quest bars. Their syrup would typically show 4 kcal per gram, but is actually closer to 2. Supposedly. That's how a bar can have so few calories and such good macros. Ultimately, if you're consistent with tracking your calories and its e…

I'm not sure what the syrup in those bars would be, but most liquid sugar products have a pretty substantial portion of water by mass.

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

#35

Post by jimmaswell »

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)

Low fat diets are actually considered unhealthy by nutritionists now, apparently.

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

#36

Post by ysleepy »

tezza wrote: post #27

> 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. C…

The body is very efficient in storing fat, more than carbs or protein. But burning fat is inefficient. But this is just from the top of my head.

I think its just a lot easier to eat a lot of carbs. Fats and protein make me much more saturated more quickly.

I don't think there is some magic formula.

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

#37

Post by maxerickson »

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…

The new FDA label standard would likely require the cupcakes to either treat the package as a serving or list the calories for both 1 cake and the entire package.

http://www.fda.gov/Food/GuidanceRegulation/GuidanceDocuments...

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

#38

Post by baddox »

alexbock wrote: post #14
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)

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…

Well who does the measurement to determine the percent error? Presumably it would be the government or some lab at the request of the government, so food manufacturers could just use that same lab.

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

#39

Post by cperciva »

thesimon wrote: post #23
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?

who checks the obscure and difficult tables

I'm not sure exactly which tables you're referring to here, but if you mean tables showing nutritional details beyond the mere number of calories: Being able to look up how many grams of carbohydrate they're consuming is a incredibly important for type 1 diabetics.

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

#40

Post by jasonjei »

tezza wrote: post #27

> 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. C…

Agreed. 500 calories from chicken or a lean protein like crab is very different from 500 calories from a pastry. What should be highlighted is amount of sugar and carbohydrates, not total calories. Not every calorie is created equally. In fact, you could almost remove carbohydrates from your diet and be unaffected, but the same isn't true of protein and good fats.
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