Among Keto dieters, no topic causes more confusion than net carbs. Let's clear it up.
Yes, you need to limit carbs on the Keto diet. But you don't need to limit all carbs.
For instance, you don't need to limit fiber because fiber doesn't raise your blood sugar. That's why net carbs don't include fiber carbs.
Net carbs are your North Star on Keto. They're the only carbs that count.
So, how do you calculate net carbs? How should you think about net carbs vs. total carbs? And how can you track net carbs smoothly and effectively on Keto? Keep reading.
What are Net Carbs?
Net carbs are carbohydrates that raise your blood sugar. That's why they're Keto kryptonite—they kick you out of ketosis.
The three main categories of net carbs are:
- Simple carbs (glucose, fructose, lactose)
- Complex carbs (dextrin and cellobiose)
- Starches (chains of glucose)
"Carby" foods are high in net carbs. We're talking about pasta, bread, grains, fruits, starchy vegetables, and table sugar.
Dying to know how to calculate net carbs? Add the three categories together. Net carbs = simple carbs + complex carbs + starches.
But that's not practical. Food labels don't delineate carbs this way.
The practical method starts with total carbs and backs out nonglycemic carbs. Here's that equation:
Net carbs = total carbs - fiber - sugar alcohols
That's it. Just subtract fiber and sugar alcohols from total carbs.
Net Carbs vs. Total Carbs
People often overlook the difference between net carbs and total carbs. Why? Because most people talk about limiting carbs (not net carbs) on Keto.
If you're limiting carbs to 20 grams daily, your eye gravitates towards "total carbs" on the recipe. Carbs are carbs, right?
Wrong. Say it with me now: net carbs are the only carbs that count on Keto.
Make a shower song out of it. "Net carbs… are the only carbs… that count!" (Bonus: your housemates get a free tutorial on Keto macros.)
Let's look at a Keto staple—the avocado—to illustrate.
One California avocado contains 11.7 grams of total carbohydrates. That sounds high until you notice that 9.2 grams of those carbs are fiber carbs.
Do the math. 11.7 grams total carbs - 9.2 grams fiber - 0 grams sugar alcohols = 2.5 grams net carbs. Keto approved!
Fiber and Sugar Alcohols: Why They Don't Count
We don't count fiber and sugar alcohols because they're nonglycemic. But why are they nonglycemic?
Because they're not digested like other carbohydrates. Instead of breaking into glucose, diffusing through the small intestine, and elevating blood sugar, they pass intact into the colon.[*][*]
Gut bacteria are waiting there. They digest fiber and sugar alcohols, creating beneficial short-chain fatty acids (like butyrate) and, depending on the state of your gut, flatulence.[*]
Fiber and sugar alcohols are food for gut critters, not human cells. That's why we don't count them.
We also don't count the sugar alcohol erythritol, but for different reasons. Erythritol does absorb through the small bowel, but it's excreted intact through urine.[*] In other words, you don't digest it.
How Many Net Carbs on Keto?
On Keto, you must keep carbs low. Keeping carbs low helps keep blood sugar and insulin levels low, triggering the fat-burning state of ketosis.[*]
Ketosis underpins the Keto diet's benefits. Ketosis typically drives weight loss, hunger control, clearer cognition, lower inflammation, and other good things.
But as you've learned, you don't need to limit all carbs to enter ketosis. You only need to limit carbs that raise blood sugar and insulin levels.
You only limit net carbs. Fiber and sugar alcohols are fine.
Your net carb limit will depend on your individual goals. If you're using Keto therapeutically—to manage epilepsy, for instance—you'll want to keep net carbs close to zero.
But most people can be more flexible. Keeping net carbs at 5-10% of daily calories (15 to 30 grams) is a good starting point.
Remember that you needn't be in therapeutic ketosis to benefit from a Keto diet. Mild nutritional ketosis will suffice.
Should you track total carbs too? That will only complicate matters. (You'll start fearing healthy, fibrous veggies.)
Just track net carbs. It's one carb metric to rule them all.
Benefits of Using Net Carbs vs. Total Carbs
You'll do better on Keto if you switch to tracking net carbs. Here's why.
#1: It's less restrictive
If you limit yourself to 20 grams of net carbs daily, you can eat avocados, berries, nuts, and many low-carb veggies. Your recipe options are endless.
But on a 20-gram total carb limit, your options evaporate. Kiss fruits, vegetables, and nuts goodbye.
Luckily, you don't have to do that. And if your friends are making that error, send them this article.
#2: It's healthier
Grandma was right: vegetables are good for you! You miss out on many crucial micronutrients if you don't eat them - and there is an abundance of low-carb veggies for you to choose from.
Fruits (the low-carb variety) and nuts are good for you too. They're high in fiber (aka, total carbs) but low in net carbs.
Most people would do well to eat more fiber. For example, higher fiber intakes are linked to better digestive and cardiovascular health.[*][*] (Note: folks with chronic gut issues like IBS or IBD often fare better on a low-fiber diet. Listen to your body.)
Bottom line? Net carb Keto keeps nutrient-dense foods in your diet. Total carb Keto does not.
Using Carb Manager to Track Net Carbs
It's helpful to know the net carb math, but don't worry about crunching numbers. Carb Manager has a built-in net carb calculator.
Set your net carb goal (adjustable anytime in settings), then log your meals. (Premium members can log meals by snapping a picture!) The app handles the rest.
Want to see if you're approaching your net carb limit? Just check the home screen in the "Daily Log" tab.
It's a simple, convenient method of tracking net carbs. Congrats, your Keto diet just got easier.