Take a breath. Put the avocado down (but keep it close, we need it). We need to talk about Net Carbs.
The Math of Not Caring (About Fiber)
Here is the secret: Your body is actually pretty bad at digesting certain types of carbohydrates. Specifically, Fiber and most Sugar Alcohols. They basically just pass through you like a tourist who doesn't speak the language—they’re technically there, but they aren't interacting with anything.
Because these carbs don't get broken down into glucose, they don't spike your insulin. And if they don't spike your insulin, they don't kick you out of Ketosis.
Total Carbs - Fiber - Sugar Alcohols = Net Carbs
Why This Matters
If you only tracked "Total Carbs," you’d be limited to eating nothing but meat, eggs, and oil. By tracking Net Carbs, the world of leafy greens, broccoli, cauliflower, and nuts opens up. You get the nutrients and the fiber (which, trust me, your bathroom scale and your digestive tract will thank you for later) without the metabolic penalty.
Do I Need a Calculator for This?
In your head? Maybe. If you’re like me and your brain stops working the moment a decimal point appears, you'll be glad to know that the Custom Keto Macro Calculator we’re building will have a dedicated "Net Carb" toggle. You can just plug in the numbers from the label, and it’ll do the subtraction for you.
Keep an eye out for it here: www.yourwebsite.com/macro-calculator
The Label Trap
Be careful, though. Food manufacturers know about this "one weird trick." They’ll slap "3g Net Carbs!" on the front of a box of highly processed cookies.
- Watch out for Maltitol: It can still spike blood sugar for many people.
- If the label looks like a chemistry textbook, be skeptical.
- Stick to whole foods where the fiber is built-in by nature, not added in a factory.
Do Your Own Homework
- Kendall, C. W., et al. (2010). "The glycemic index: methodology and clinical implications." Progress in Molecular Biology and Translational Science.
- Wolever, T. M., et al. (1991). "The glycemic index: theoretical basis and clinical applications." American Journal of Clinical Nutrition.
- Anderson, J. W., et al. (2009). "Health benefits of dietary fiber." Nutrition Reviews.