T Nation

'Net Carbs'


I understand how they arrive at the "net carbs" number (carbs - fiber= net carbs) and I've read some b.s. explanations about how they come to that conclusion, but it's hard for me to buy into that theory. Are they really implying that fiber completely offsets carbs? Does anyone here actually count 'net carbs' as opposed to actual carbs? Is this just creative marketing to make people feel better about the amount of carbs they consume?


The idea is that fiber lowers the insulin response from carbohydrates,

Pretty sure this is because fiber is one of that last nutrients to leave the stomach, into the small intestine.

To answer your question, I don't count fiber as carbs... So I guess I would use "net" carbs?

But I think "net" carbs only appears on protein bars, I haven't seen it anywhere else. My fiber sources are vegetables, my carb sources are yams... So it's simple for me


Technically, yes fiber is a complex carb. However I don't count fiber as "carbs". The body cannot produce energy from fiber, its actually just the opposite.

So if I'm aiming for 150g of "net" carbs, but I took in 175g overall, with 30g coming from fiber, I'm good :slightly_smiling:


Its not that the fibre offsets carbs, its that the total carb figure diclosed included fibre in the first place. So then the theory that some fibre is non soluble and therefore does not contain any digestible calories is why they deduct this figure to arrive at net carbs. However take this with a pinch of salt because afaik not all fibre is insoluble and will contain some calories but will be deducted nonetheless.

There is a similar probelm when they use the term 'impact carbs' where they take away sugar alcohols and polyols and leave the remaining carbs when these sugar alcohols do include some amount of calories in almost all cases


Pretty much this. It's confusing because everyone, and every company, can do something different. As far as I know, there's no universal, enforced-by-law, commonly-accepted definition for "net carbs" so it's essentially a marketing thing.

Some companies may or may not count fiber in "net carbs", some may or may not count sugar alcohols, I vaguely remember reading some crap magazine talk about how whole fruit doesn't count toward daily "net carbs" because they're "unprocessed".

Your best bet is to decide what rules/guidelines you're going to do for you and your nutrition, and stick to it. Similar to how most/almost all people don't count the protein from oatmeal or potatoes in their "net protein" for the day, or some may or may not count the fat in their skinless chicken breasts or spray cooking oil in their daily "net fat" intake. Figure out what you'll apply to yourself, based on how much time/effort you want to invest in tracking things, keep those rules intact, and make adjustments as needed.


For clarification- I'm not asking whether or not to count fiber as carbs. I'm saying, for example, on those Quest bars they have 22g/carbs but 19g/fiber so they claim the bars only have 3g/net carbs. That is a HUGE difference especially when trying to hit 50g/carbs a day. Obviously if I'm going that route I probably shouldn't be eating Quest bars in the first place, but how am I suppose to accurately count these carbs?


Yes i know this is an old thread but i was about to post one until coming across this one.

Soo whats everyones opinions on net carbs? It seems too good to be true to me. Can you really just subtract fiber from the total carbohydrates? If that was true why would they even include it in the first place?



Yes you can, because fiber has no impact on blood sugar and no insulin response. It's listed that way because of FDA labeling requirements. The carb is based on total available carbs, not actual digestible carbs. Everything is tested in a laboratory environment where all food is burned in a calomimeter process. Starch and cellulose are counted as providing the same calories to the body, and we all know that is erroneous.

So, 'net carbs' is accurate based on FDA guidelines.


So all types of fiber are indigestable? Or is it just insoluable fiber? And you subtract sugar alcohol too right? But i thought certain sugar alcohols get absorbed


I dont know but i hope so. I have found some AWESOME tortillas for $2 for 8 of them have 14g of carbs and 9g of fiber per tortilla. Along with 5g of protein and a 1g fat.


Is it these?



Nope these but those are good too.




Gotcha. I haven't seen that brand in my neck of the woods.

Low-carb tortillas are a mainstay of my diet--have them virtually every day. I scorch them (lightly) in a dry frying pan over high heat first--great flavor!


Oh fuck yeah im getting some. I cant believe i never knrw shit about net carbs. This seems too good to be true. Has anyone dieted while going by net carbs? What about anyone with diabetes Out there? Have you calculated insulin use to net carbs and it worked out?


Anyone got any tortilla recipes with 50g protein, 30ish grams carbs and 10 g fat? Ill love you long time.


The digestibility of fiber varies from person to person. Depends on what kinds and how much of certain bacterias in your gut. Generally the more you eat fiber, the more bacterias you will have that can ferment the fibers.

Fermented fiber will create short chain fatty acids, which are digested directly into the blood stream. No affect on blood sugar. Sugar alcohols are absorbed as five carbon type sugars, also no impact on blood sugar.

So the 'net carbs' label, despite not having an approved FDA meaning, generally just tells how much of the carbs in a product will enter the blood as glucose or fructose.


I keep baked chicken breast on hand at all times. I throw the tortilla(s) in the pan to scorch while I'm slicing/weighing my chicken (I do 3 oz per tortilla):

1 tortilla + 3 oz baked chicken breast = 220 cal/32 g protein/5 g net carbs/5 g fat

I also keep lean (96/4) ground beef on hand. I use 4 oz/tortilla:

1 tortilla + 4 oz 96/4 ground beef = 215 cals/29 g pro/5 g net carbs/6 g fat

You could use these chicken/beef tortillas as a base, and add whatever you want/need to hit your macros. (I add pickles, banana peppers and mustard for 'free').


A couple of points I'll add or maybe fix here.

1) Humans do not have the enzymes to break down fiber, however our gut bacteria does. Our gut bacteria does not break it down to glucose though, it breaks it down to butyrate (short chain fatty acids) at a maximum amount of about 1 gram of butyrate per 10 grams of fiber (or about 1 calorie per gram of fiber).

2) Food items nowadays sometimes remove fiber from the carbohydrates on the label in the first place, so you may find a food item that lists 20 grams of carbs and 8 grams of fiber that actually has 12 grams of effective carbs, or that has 20 grams of effective carbs (PLUS 8 grams of fiber). You can not just subtract the fiber from the carbs and assume that they used one method or the other. Again fiber is counted in the atwater carb formula as carbs, but the people who do the labelling sometimes keep them in and sometimes take the out. My preference is to take total calories, subtract fat and protein calories and divide by 4. Common industry practice is to list CALORIES as protein x 4, fat x 9 and carb MINUS insoluble fiber x 4 to get the calorie total. http://www.ars.usda.gov/Main/docs.htm?docid=6233

3) Remember as well that fructose, or half of the sugar in a food, if it is not a huge sugar bomb, will never enter circulation and will be turned into other macros. The liver can process about 1 gram of fructose per hour into liver glycogen. It will turn excess into triglycerides and at above about a gram per hour there will be some spillover of fructose into the blood where it is problematic because it causes about 10x the glycation as glucose. If you have a 100 blood glucose and a 1 (mg/dl) blood fructose it is like having a 110 blood sugar.


Not a tortilla per say but I use this either as a pizza base, or as a flatbread, etc. Easy to do and can add/subtract ingredients depending on your goals, tastes, etc. Posted this elsewhere on the site re low carb pizza base:

2 tbsp. coconut flour
2 tbsp. milled flaxseed
1/2 tsp baking powder
1/2 tsp. xanthan gum (useful binding agent for alternative flours)
1-2 eggs, or one whole plus 1-2 whites (there is no real need for 3 eggs)
garlic and herb salt to taste (greatly helps to give the crust a savoury taste; pepper and other herbs work well too)
1/2 cup of quark
small handful grated cheddar (I go for 50% reduced fat)

The quark makes the batter quite thin so you can thicken it by adding some more coconut flour and/or cheddar. However, this is another advantage for me because it pours like a pancake mix onto the greaseproof paper. You can then let it form into a very thin pizza crust. Bake as instructed.

As mentioned, these steps will significantly lower the overall calories from fat while not affecting the taste.