Hi.
In the nutrition facts on a grains based foot item I have (unfortunately I don’t know the English word for it), it says that 100g yields about 200 calories and contain about 50g dietary fiber.
As dietary fibers to a lesser degree is absorbed by the intestines, does it mean that out of the 200 calories I actually get maybe just 100 calories? Or is it likely that the 200 calories which is says on the nutrition facts label adjust for the reduced absorption of fiber? In other words, will eating 100g of this food item give me 200 calories, or closer to 100 calories?
UPDATE: I just found that the English word is “bran”, so the food item is just (ground ?) wheat bran.
I would look up the difference between soluble and insoluble fiber. Insoluble is not absorbed in any way, and so doesn’t get turned into energy. Soluble fiber does get consume by intestinal bacterial, and indirectly is turned into energy - but the yield isn’t 100%. You could probably look up the specific food and figure out the split of types of fiber.
Here’s the thing, especially if you are in the USA.
Here’s the most recent guidelines I can find, but I believe there’s a big change happening soon: https://www.fda.gov/regulatory-information/search-fda-guidance-documents/guidance-industry-food-labeling-guide
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Most companies in the U.S., especially if its a diet/health marketed product, will in fact pre-manipulate the numbers - Fiber one brownies are a great example — they are listed at 70 calories, but if you do the actual macro calculation, it comes up to like 109, 110 or something. So if you yourself then decide to subtract fiber calories from that 70, your essentially doubling the amount of fiber calories, and your calculations will be off.
This manipulation is also often done a LOT with net carbs, etc.
And then of course you get into the whole bioavailability…..its just a hot mess.
I personally hate when companies do this. Absorption or not, just give the unmanipulated information, and let consumers decide how they want to calculate it. Especially given how much room for error they are allowed.
Dr Giles Yeo has research on caloric availability. I came across some of his videos on YouTube. Essentially, we absorb less than 100% of calories from food. According to his research, protein is around 70% and foods high in fiber are <90%. Processed foods tend to be closer to 100%. He gives an example of corn on the cob having a lower caloric availability than store-bought corn tortillas. Industrial processing of food tends to remove some fiber (and nutrients) and also changes it into a form in which our bodies are more able to absorb calories. Processed foods tend to have more caloric availability and less nutrients than their whole-food counterparts.
In some cases there may be a tradeoff. I think ground flaxseed has a higher caloric availability than whole flaxseeds (I have no idea by how much), but this isn’t necessarily bad because I’ve read absorption of nutrients is higher in ground flaxseed.
He makes some compelling arguments that some nutrition plans (diets) may help people lose weight, but not for the the reasons generally claimed. For example, Paleo and Keto tend to be high in protein, so he argues people may be effectively consuming fewer calories than they think. In addition, protein is more satiating than fat and carbs and can help with things like preventing overeating or sticking to time-restricted eating (or fasting).
Your example might be a bit extreme though of 100 vs 200 calories.
Personally I’d go off the 200 calories mentioned on the label. If it says 100g is 200 calories… Then I log 100g as 200 calories. Too much brain work and effort to worry to that level for me.
I suppose it depends on what your nutrition goals are at the end of the day. For me it’s weight loss, so if I go off the 200 then I’m sticking on my calorie deficit goal .. if the reality is that it’s actually closer to 100 calories then even better, I’m in more of a calorie deficit.
Put it this way fiber as in things like broccoli or bran muffins or prunes won’t be the reason you get fat plus you’ll eat less regardless because it fills you up faster than other foods. Plus it helps you poop more regularly and that never hurt anyone so don’t worry about calories. You wanna worry about something then worry about making the gap in between your last n first meal from yesterday wider and wider. The longer you can go without breakfast the better! Try it trust me you’ll wonder why you aren’t eating as much as you used to .
There’s a lot of factors at play, soluble vs insoluble fiber affects how digestable it is, as well as your gut microbiome. Personally I go with the easy solution of counting 1g fibre as 2 cals, rather than the 4 it is on a nutrition label. This has more or less worked for me and has made it so I’m not unexpectedly dropping weight when eating high fiber foods (I’m a bodybuilder, so losing weight is not always my goal).
you can verify by using that 1g fat= 9 calories and 1g protein or carbs = 4 calories. i would say probably its not including fiber, since technically they dont give you energy, which is what calories measure.