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"Net" carbs

Spiker

Spiker

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US food labelling shows "Net" carbs, based on the assumption that grams of fibre can be subtracted from grams of carbs, in some way. European food labelling just shows the actual carbs.

What's the basis of this net carb assumption and does it have any relevance for diabetics, T1 or T2?

I can see that fibre delays absorption and that might help T2s. But for T1s is the claim that some of the carbs are actually indigestible fibre that can't even be digested by gut bacteria? Are they saying that on a bolus insulin regime, you would inject only for the "net" carbs?

To me this seems close to pseudoscience, or a food industry ploy, but net carbs seem to be "official" in the US. Can anyone shed any light?
 
US net carb = UK total carb "I THINK" and don't jab yourself with this info.
their total carb includes fiber, which is deducted to give a net carb, which should be the same as a UK total carb which is supose to have the fiber already deducted. , well it's suppose to anyway. I haven't doubled checked for the UK as I'm aussie.
there should be UK carb numbers on the net, for food you can cross reference against
 
To me this seems close to pseudoscience
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How so? Humans don't have the digestive encymes to split up things like cellulose therefore injecting insulin for it would be silly despite cellulose consisting of thousands of linked glucose molecules. If you are a diabetic sheep, things might be different however.

I suppose the US way if listing is technically correct whereas then European way is more helpful
 
It would be pseudoscience if they were saying a neutral material could be offset against a glycemic material. On examination it looks more like a generalisation. While humans can't digest cellulose, humans have digestive bacteria to digest some fibre but not other kinds. The US are making a few generalisations - 1. that everything that isn't water, protein, fat or ash is "carbs", and that out of those "carbs", none of the fiber makes any glycemic contribution.
 
I read somewhere that you should subtract the fibre from the total carbs amount when calculating doses - it was either on BDEC website or in Think like a pancreas book. That is, you shouldn't bolus for fibre. But I can't remember why exactly.
 
Dietary fibre is now defined as
food material, particularly plant material, that is not hydrolysed by enzymes secreted by the human digestive tract but that may be digested by microflora in the gut.
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Those fibres that are digested in the gut are not going to add much if anything to glucose levels since fermentation products are mostly short chain fatty acids. (they do have calories and in Europe these are counted at 2 cal per g)

There are various methods of analysis which produce differing amounts of total fibre. In the past the method used in the UK was very different to the one in the US so resulted in different amounts of fibre.
Many manufacturers still rely on the 'official' tables to calculate fibre in recipes so you can't (or couldn't) make comparisons with foods from the US with or without fibre.
eg: For the same wholemeal bread , the AOAC method as used in the UA resulted in 7.4g/100g of fibre, the Englyst method used until recently in the UK resulted in 5.8g/100g (if you are eating a lot of fibrous foods the amounts could mount up)

There is now more of an international agreement and the UK is gradually changing the methods it uses
.http://blog.nutritionprogram.co.uk/2012/05/07/fibre-nsp-or-aoac/
This is the source she links to and obviously got most of her blog from.
http://www.ifst.org/dietary-fibre
Bottom Line
Whatever method is used since the labels in Europe already have fibre deducted there isn't a problem , you don't have to add or subtract anything
( unless of course you are using websites that include foods from the USDA data base or are entered by people elsewhere in the world which confuses things immensely)
 
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