Net Carbs…is it really a thing?

PastaAh the new year! A time to re-commit to exercise and diet goals and for all of us with diabetes, getting or keeping that A1c low. And after all the amazing meals between Thanksgiving and New Year’s, I’m finding it a little hard to  get back on the bandwagon. There were so many reasons to enjoy so many delicious foods for a while there, but now, alas, it’s time to buckle down and make food choices that can help me continue to strive for an A1c under 7%. Which leads me to this question: Can net carbs really be trusted?

Net carbs are supposedly the amount of carbs that will actually hit your system after subtracting the grams of fiber from a total carb count of a food. Many so-called “diabetes friendly” foods make this claim, but I’ve been burned by it too many times in the past. Most notably in my mind with a brand of pasta called “Dreamfields” which claims to only have about five grams of carbohydrates after deducting the fiber from the total count. This, in summary, did not work for me, and I ended up taking as much insulin as I would have for normal pasta.

But the net carb claim isn’t going away, and some folks even apply it to high-fiber fruits and vegetables.  I haven’t had consistent experience with it and in fact, it makes bolusing more complicated because it can often lead to some, but not all of the carbs hitting me, and me not being able to predict how much that will be. Somewhere between the total carb count and the net carb count, I guess.

Are there any of you that follow the net carbs rules in a hard and fast manner that you have found to be effective? Or is this one rule to ditch in 2014?

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In my experience this was more of a thing for the low carb dieters like when I was on Atkins. Even all their documentation though warns to be wary of the net carb calculation and it is not always accurate. The best way is to count each and every carb.

My rule of thumb for many years (although I can’t recall the source) has been to subtract the fiber from the carbs if there are more than three grams in a serving size. I eat mostly vegetarian and this has worked really well for things like beans and lentils.

I haven’t tried this with foods marketed as having a low “net carb” count, mostly because I’m suspicious of those claims (what did they do with all the carbs and where did they go?). As with many things diabetes-related, it may come down to trial and error to see whether to subtract the fiber or treat something like a regular food.

My dietitian told me that IF a foodstuff had 5 grams of fiber (no less), I could deduct 2.5 grams of carbohydrates. So the rule is: Must be 5gm or over of fiber to be subtracted. If so, deduct 1/2 of the amount of fiber from the carb count. I have never been able to tell whether it works, but my dietitian has been right about everything else she has told me!

I don’t do net carbs at all, not even with Dave’s Killer Bread and his 7gm fiber/slice….
I find that with things that advertise “net carbs” it’s because they’ve added a ton of fiber. And when they do that, it’s already processed. Which for me, means it goes STRAIGHT to my blood sugar… *grumble*
The rule that Tim talks about is a good one – that’s what my boss uses too.

I swear when I did my carb training (15-20 years ago) they said to subtract the total fiber from the carbs…recently I have heard Tim’s recommendations to subtract 1/2 the fiber if it is more than 4 grams of fiber. I don’t really give it much credit and I just bolus as usual! Also, I don’t think I carb count carefully enough to notice a difference of a few grams of carbs. I haven’t tried products marketed at low “net carbs”…but I am a skeptical person at best 🙂

My official “Certified Diabetes Education” was to subtract the fiber IF it exceeded 5g. Always sounded fishy and arbitrary to me. How could additional 1g of fiber make my entire meal-bolus 4g less?

I call BS on the whole Net Carbs thing (and I am completely turned off by a respected low-glucose-treatment company whose product line recently expanded to include snacks with “net carbs” on the label). Carbs are carbs, fiber is fiber.

My belief is that, for non-D folks, fiber (and sugar alcohols) are digested so slowly that the normal or T2-pancreas can easily keep up –hence no blood sugar spike. It doesn’t work that way for us. The carbs being digested slower means it needs a square/dual/extended bolus to cover them in time, but they can’t be ignored altogether.

It’s a marketing gimmick that unnecessarily complicates things. I’d rather have the “bad” kind of carbs…at leasr I know what to do with them.

Once more a comment from across that pond: I’ve not heard of “net carbs” before today. That sounds like another English-language invention (not neccessarily a bad thing. I rather like the convenience of my computer and such).

As this is new, I obviously don’t follow those rules. And instead fall back (in case of emergencies) on my little pocket book of carbs, bolusing too high when in doubt (because lows, when wary for them, are easier to fix) and generous rules of thumb (like: bread is composed of 50% carbs. I don’t care what type of bread, I’ll always calculate with 50% weight carbs).

I’ll go with Scott Es summary: unnecessarily complicated.

We use Dreamfield Pasta all the time and I do bolus about 25% less for them than regular pasta. Certainly not the 75% less or so the net carbs would have it be, but I do find my insulin needs are slightly reduced and the post meal spikes aren’t as severe.

My guess, however, is that I’d see similar results with any whole-grained pasta.

This is a FASCINATING group of responses folks, I am amazed at how many approaches there are to this. And also that someone from Europe hasn’t heard of this on her side of the pond. Very interesting. I need to ramp up my carb counting anyways but this is a whole other level.

Ah yes, but the mere reason that I have not heard of it doesn’t mean it’s not known here. Just that I live in a shell 🙂

Also .. erm … “his” side of the pond in this case. Not that I want the whole side for myself or anything, but but …

Floh! I am mortified! My Aunts name was Floh and I assumed you were a female, and you don’t post too many pics on your blog 🙂 My apologies!! HIS SIDE OF THE POND!

You might find that Europeans and people from Australia/New Zealand are a bit baffled by the ‘net carbs’ thing because nutrition labels there categorize fibre as it’s own constituent (ie; not a carbohydrate), so the carb counts are already excluding fibre. Where a US label might say:

Carbohydrate: 10g
— Sugars: 5g
— Fiber: 5g

(You’d subtract 5g fibre to calculate 5g net carbs)

A label from Europe or Oceania might read:

Carbohydrate: 5g
— Sugars: 5g
Dietary Fibre: 5g

(Fibre is not considered a carbohydrate, so it is not listed in the total carbohydrate count but rather as a separate constituent of the product, like fat or protein would be)

And both labels are for the same product! If you try to deduct fibre from the European/Oceanic label, you’re going to accidentally tell yourself “wow, this cookie has no net carbs!” (like I did when I first started eating low carb, and couldn’t figure out why nothing was happening!)

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