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

scientificamerican.com

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

#61

Post by moby_click »

nck4222 wrote: post #44
ysleepy wrote: post #36

Earlier quoted context omitted.

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.

In general your body doesn't take the fat you eat and store it as fat. It takes the excess sugars and stores them as fat.

Maybe we have differing ideas of "general" but in healthy non-overeating people, the fatty acid profile in the body is reasonably close to the dietary profile. There is some conversion like elongation and desaturation of essential fatty acids and you can also find some short-chain fatty acids from fermentation in the gut, but it takes excessive amounts of carbohydrates for de novo lipogenesis. Also, what else would the body do with dietary fat other than storing? A fatty meal would quickly overwhelm the capacity of the blood if there was no mechanism to quickly dispose of dietary fat.

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

#62

Post by analog31 »

alexbock wrote: post #11
analog31 wrote: post #10

Earlier quoted context omitted.

I suspect it's not a large effect for bread. My family bakes our own bread, and I would say without having measured it on a scale, that there's not a noticeable loss of weight from one end of the process to the other. Also, you'd notice the stuff bubbling if there were a significant production of CO2. I've also made beer, and it bubbles like crazy once it gets working. One possible difference is that bread is made fr…

If anyone can find a reference on the amount of CO2 produced during bread making it would be easy enough to calculate. I haven't been able to find any relevant sources except this old one [1] which mentions that the alcohol content in bread can be as high as 1.9 percent (which sounds quite high to me, but it's hard to critique when they don't explain their methodology). [1] http://www.ncbi.nlm.nih.gov/pmc/articles/PM…

Well, all I can offer is... tonight is baking night. I will weigh the ingredients, equipment, the risen dough, and the final product.

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

#63

Post by street »

chris_va wrote: post #52
street wrote: post #49

Earlier quoted context omitted.

>So, for example, person A can eat 3000 calories of cookies per day, but would gain weight on 3000 calories of rice. Person B could be the opposite. From the paper, it looks like genetics is a factor, though epigenetic factors and microbiome seem more important. That's not at all what that paper says. It describes that blood glucose response to various foods can differ between people (and shows to extreme outliers as…

Sigh. Yes, it is well supported by the research, did you actually read it? I actually had a nice phone call with the lab that produced this paper. You can explain a percentage of weight changes by calorie intake, but the factors that explain glucose curves (and thus uptake of calories) require far more data (like genetics, etc).

Your call with the lab is an attempt to appeal to authority. Also, thanks for the "sigh".

I read your link. It's about blood glucose. Not about weight. The crux of your argument is that blood glucose response equals uptake of calories, which is not supported by your link, and which is not true. If it were, you could eat 5000 calories of fat in a day, have no blood glucose response, thus not get fat.

Are you really trying to claim that the outlier participants of whom the blood glucose plots are shown in your link are unable to use any of the calories in bananas/cookies, because they had no blood glucose response?

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

#64

Post by TillE »

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.

The 100g listing is mandatory, but many products will have an extra column for portions where it makes sense. If they don't, you might need to pull out a calculator to figure out how much sugar is in x bits of chocolate, but it makes comparing different products much simpler.

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

#65

Post by spatular »

nomel wrote: post #57
spatular wrote: post #48

Earlier quoted context omitted.

This isn't so. Quoting [1], energy dissipated as side-effect heat during gestation and storage: Carbohydrates: 5 to 15% of the energy consumed Protein: 20 to 35% Fats: at most 5 to 15% [1] https://en.wikipedia.org/wiki/Specific_dynamic_action

> Protein: 20 to 35% Doesn't this assume that you're starving [1]? Proteins are a last resort, and since it's somewhat toxic to convert them, they're simply not processed if it can be avoided [2]. [1] https://en.wikipedia.org/wiki/Gluconeogenesis "the process occurs during periods of fasting, starvation, low-carbohydrate diets, or intense exercise." [2] http://antranik.org/the-catabolism-of-fats-and-proteins-for-...

Yes, looks like this. And in addition in average human this pathway is limited to 300g amino-acids -> glucose per day if I remember correctly. Still what should happen if protein intake is tripled say from 50g/day to 150g/day? Excess amino acids have to go somewhere...

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

#66

Post by jobigoud »

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.

I often find it more convenient actually because often you don't eat "one serving". Consider breakfast cereals, rice or pastas. Having the per 100g values allows you to actually compare one item to the next. When I'm the US I find myself trying to convert back the per serving to per 100g to get back to known territory.

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

#67

Post by goldenkey »

snewk wrote: post #56
maxerickson wrote: post #31

Earlier quoted context omitted.

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

don't eat olestra

Also dont eat fish oil capsules on an empty stomach. Your Herman Miller chair will receive a present that you could not help deliver. The oil will literally leak out since there is no other digested food to keep it behind your sphinter. One of the weirdest stenches of partially digested fish oil bile that resists all attempts to nuetralize the stain and odor. I am passing on great wisdom as funny and crude as it sounds..(That chair was eventually sold at a huge discount and was probably bleached. Steelcase Worklounge is better anyhow so I'm not totally out of shape about it.)

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

#68

Post by chris_va »

street wrote: post #63
chris_va wrote: post #52

Earlier quoted context omitted.

Sigh. Yes, it is well supported by the research, did you actually read it? I actually had a nice phone call with the lab that produced this paper. You can explain a percentage of weight changes by calorie intake, but the factors that explain glucose curves (and thus uptake of calories) require far more data (like genetics, etc).

Your call with the lab is an attempt to appeal to authority. Also, thanks for the "sigh". I read your link. It's about blood glucose. Not about weight. The crux of your argument is that blood glucose response equals uptake of calories, which is not supported by your link, and which is not true. If it were, you could eat 5000 calories of fat in a day, have no blood glucose response, thus not get fat. Are you really tr…

Apologies, but the "sigh" was for the "not supported by the study, and also nonsense" comment. I find it annoying when supported arguments are dismissed out of hand without compelling counter evidence. It sounds childish, like "no you are wrong, because naaaah". If that wasn't what you meant, please be more thoughtful.

Regardless, we can talk about metabolic pathways. If you consume carbohydrates, they eventually get dumped into your bloodstream as glucose (minus fructose, which is special). The level of glucose then absorbed into fat cells is regulated by insulin, and insulin production (while more complicated) is determined by the level of glucose in the blood.

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

#69

Post by spoofball »

mysterypie wrote: post #16
cma wrote: post #4

Earlier quoted context omitted.

The protein test was famously faked with melamine in the Chinese dog-food scandal that killed dogs and resulted in a recall: https://en.wikipedia.org/wiki/2007_pet_food_recalls

I was following that case closely back in 2007 because of my pet (thankfully not affected). An astonishing thing I learned was that practically every brand of cat food and dog food in North America is/was manufactured by a single company called Menu Foods in Streetsville, Ontario, Canada. The pet food "brands" don't have their own factories. They all contract it out to the same place. A few journalists remarked on th…

the majority of pet food is meat not fit for human consumption. [1]

if you aren't feeding your pet meat that you eat, it's living on extreme crap.

[1]: http://www.dogfoodadvisor.com/dog-food-industry-exposed/unfi...

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

#70

Post by rjsamson »

rhinoceraptor wrote: post #45
ysleepy wrote: post #36

Earlier quoted context omitted.

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.

> burning fat is inefficient Huh? The body is perfectly happy to burn fat. You just have to give it the right conditions. In fact, the body can get practically all its energy from fat, it's called ketosis. You can achieve a state of ketosis either through a high fat, low carb diet or fasting.

Yup. I've been doing a ketogenic diet the past 6 weeks and it's pretty awesome.
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