Low Carb Diet and Fiber

I wasn't too keen on the idea of tracking net carbs. I couldn't understand how it's possible to eat a tortilla and a wrap on the same day and still be eating a low carb diet! My tortillas have 3g net carbs and my wraps have 4g net carbs. What I wanted to do is track total carbs and only get my carbs from vegetables and fruits. I've read the dangers of not getting enough fiber and I definitely want to avoid those consequences. So I thought, ok I'll get a fiber supplement.

I have since then read about why fiber "cancels" out carbs: "because it doesn’t raise blood glucose. Fiber can provide calories, not as glucose, but as products of fermentation in the colon."

Here's my question. Say I do get all my carbs from veggies and fruit and use a supplement to hit my goal of 25g of fiber...does the fiber cancel out all those carbs and make it like I ate zero??

Is tracking net carbs a must?

Replies

  • janejellyroll
    janejellyroll Posts: 25,763 Member
    A must for what?

    Doing a low carb diet? Losing weight? Something else?
  • lemurcat2
    lemurcat2 Posts: 7,885 Member
    edited March 2020
    Fiber doesn't cancel out carbs. Fiber is simply counted as a carb on US and Canadian nutrition information but doesn't operate like other carbs (we get only limited cals from them, they don't raise blood sugar, and most significantly for keto purposes, they don't prevent ketosis) so there's no need to count them if you are counting carbs.

    Assuming you are in the US or Canada, it's not possible to eat 0 net carbs if you eat fruit and veg, because nothing is less than 0 net carbs -- each gram of fiber (including that in your supplement) counts as a gram of carb.

    (If not in the US or Canada you shouldn't subtract fiber as labels are already net carb.)

    Without net carbs, you'd be eating very little fruit and veg. (Even with net carbs I personally found it hard to fit in fruit on keto, and my only sources of carbs were veg, a serving or two of nuts and seeds, and occasional plain greek yogurt or cottage cheese. I do eat quite a lot of veg, though, which is why I could get 25 g of fiber without supplementing.)

    Tracking net carbs is not a must, of course. It's just what is actually relevant to getting into ketosis. If you are just doing a lower carb diet it might make more sense to track total carbs. I used to eat around 100 g carbs, and didn't bother figuring out the net carbs (although I did track fiber since I think fiber is important).
  • kimny72
    kimny72 Posts: 16,011 Member
    go52182 wrote: »
    I wasn't too keen on the idea of tracking net carbs. I couldn't understand how it's possible to eat a tortilla and a wrap on the same day and still be eating a low carb diet! My tortillas have 3g net carbs and my wraps have 4g net carbs. What I wanted to do is track total carbs and only get my carbs from vegetables and fruits. I've read the dangers of not getting enough fiber and I definitely want to avoid those consequences. So I thought, ok I'll get a fiber supplement.

    I have since then read about why fiber "cancels" out carbs: "because it doesn’t raise blood glucose. Fiber can provide calories, not as glucose, but as products of fermentation in the colon."

    Here's my question. Say I do get all my carbs from veggies and fruit and use a supplement to hit my goal of 25g of fiber...does the fiber cancel out all those carbs and make it like I ate zero??

    Is tracking net carbs a must?

    The fiber from a supplement also is carbs. If you buy psyllium husk capsules and it's 2g of fiber per capsule it will also be 2g of carbs per capsule. It's not that fiber cancels out carbs. Fiber is a type of carb, that for whatever reason, the low carb rule book deems acceptable, I assume something about blood sugar levels.
  • leggup
    leggup Posts: 2,942 Member
    I'm confused. Are you asking why net vs total? Info: https://www.webmd.com/women/features/net-carb-debate

    And personal experience: I've never counted carbs and I've always succeeded in weight loss because I count calories. I'm a vegetarian and eat both simple and complex carbohydrates. I probably eat more complex carbs than the SAD.
  • amusedmonkey
    amusedmonkey Posts: 10,330 Member
    You must have misunderstood. Nothing cancels anything. When you eat something that has 50 carbs, 25 of which is fiber, you're basically just subtracting fiber out of your total carb count to calculate net carbs. Fiber doesn't act the same way other carbs do, that's why those who do low carb diets subtract it. It doesn't mean 25 grams of carbs would cancel out the other 25. It just means 25 of those carbs won't have the same effect as the other 25.

    You don't have to calculate net carbs if you don't want to if your goal is to lose weight. People calculate it just to give themselves an allowance of "effective carbs" in order to have a clear number to aim for, not muddled by fiber variations. Weight loss is a product of calories, so if you find a low carb diet easier but don't feel like calculating net carbs, you don't have to. Just keep an eye on your calories while eating foods you consider low carb and go with it, As long as your calories in check you should do fine.
  • go52182
    go52182 Posts: 133 Member
    leggup wrote: »
    I've tried to research on my own but this article was super helpful. I knew this "net carb" business was hogwash. It just didn't make sense to me at all. Like those Atkins snacks with a ton of carbs and added fiber so they're only 4g net carbs. Just never made sense...

    Thanks, ladies.
  • amusedmonkey
    amusedmonkey Posts: 10,330 Member
    go52182 wrote: »
    leggup wrote: »
    I've tried to research on my own but this article was super helpful. I knew this "net carb" business was hogwash. It just didn't make sense to me at all. Like those Atkins snacks with a ton of carbs and added fiber so they're only 4g net carbs. Just never made sense...

    Thanks, ladies.

    It's not hogwash where it matters, for people with diabetes who take insulin it's important to treat fiber differently for a proper dose. In those cases fiber carbs are calculated at half the value and it does matter. For weight loss, not so much.