You’d think it would be easy…..no way! The ADA decided a few years back to make it waaaay more complicated. Why do simple subtraction when you can have more rules and regulations. Right?
Okay, here goes, the “official” rules for subtracting fiber
If the Fiber count is more than 5 grams ………….
subtract half the fiber
If not more than 5 grams
don’t subtract it. 
This is because they decided that some of the fiber does eventually break down into a form that can be used by your body (hence only half).
Now you didn’t think you’d just get away with this did you?
Sugar Alcohols
Same rule, if more than 5 grams subtract half, because some does get utilized by your system.
However (hee hee) if Erythritol is the only sugar alcohol listed subtract all of it! Are you making a cheat-sheet up?
I have a fool-proof method for dealing with this, I don’t subtract any fiber. Nobody says you have to subtract it! Now I realize that for people on an extremely low-carb diet, every carb counts. Also for people dosing with insulin it could be a consideration. But lets face it, there aren’t many foods with more than 5 grams of fiber per serving, and if so it’s only 2 or 3 grams to subtract that we’re talking about usually.
Now there are some products with special consideration, such as Dreamfields pasta, which is supposed to have a “special coating”. I treat them with my meter. I eat them and test to see how they impact my numbers. Regardless of what the “hype” says, my meter has the final word on it.
Also, don’t expect to see this method everywhere. I did a “google” just to see what was out there and many things showed up. In most they just said subtract all of the fiber to get the “net” carbs. Most didn’t even mention if more than 5 grams.
So basically folks how you decide to do it is up to you. Just never let it be said that I didn’t give you the “official” method.
Lizzy
© EMO 4/12
Knowledge is Power
When I was diagnosed, close to 11 years ago, I was told “you are diabetic”, given a prescription for some medication, and told to wait for a nurse to come in and give me an insulin shot. When I picked up the prescription I was given a 10-page booklet telling me “All About How to Mange Diabetes”, and sent on my way. That was the extent of my “education”. 
Hi Lizzy.
What’ s the name of the bread you use?
Thanks in advance.
Hi Christine,
It’s Natures’s Own Double Fiber. It doesn’t say it’s low carb, but read the carbs on the label.
Lizzy
My perinatalogist (diabetes and/or other complication specialist for pregnant women) discussed “net carbs” in our training class. Her instructions? DO NOT SUBTRACT ANYTHING.
Count all carbs and limit your intake of those. Lots of us were pretty disappointed. But hey, the “diet” is working to keep my numbers at non-diabetic levels without any medication at this point, so I can’t complain (much). 
Thanks Lizzy!
Diagnosed March 1 with type 2 and have been low carbing ever since. I have been wondering about this whole “count, subtract, add” fiber rules………..just like everything else, sounds like I need to keep listening to my meter
Susan D
You’re right Susan, it’s like “Much Ado About Nothing” to me, too much work for subtracting a few grams from the total carbs. A lot of people want to do it though, and even diabetes counselors advise doing it. Go figure!
I always listen to my meter first! It doesn’t lie, at least not much.
Lizzy
I started eating a lot more fiber when I got pregnant, especially since I wanted to avoid pregnancy constipation. I usually eat it the form of wheat toast (the double-fiber kind) in the morning with breakfast but will down a glass of metamucil if I skip breakfast. Fruits and veggies are great too.BTW, the fiber one bars are awesome but don’t eat too many your first few days cause you’ll get nasty stomach aches since your body isn’t used to so much fiber.
Hi Erhan,
A lot of people can’t handle regular toast with breakfast without their numbers spiking, but there’s a form of high fiber low-carb bread that I use that works for me. You’re right about the fiber one bars, you have to be careful of eating too many at once or you get a little too much fiber.
Lizzy