If you’re on a ketogenic diet, you may be asking whether you should count the net carbs or the total carbohydrates. The keto diet restricts carb intake and replaces it with fat to achieve ketosis, a state where your body burns fat for energy.
If you want to know the answer or you’re interested in understanding how food labels work, this information about counting total carbs and net carbs will help you.
Total Carbs vs. Net Carbs
If you check food labels, you’ll see the total carbs on the list. Total carbs are essentially the total number of carbohydrates, including starches (digestible complex carbohydrates), sugar alcohols, and plant fibers (indigestible complex carbohydrates) minus all the things that are protein, fat, minerals and whatever else might be present in a food.
Total carbohydrates is measured through an indirect subtraction method. It’s relying on a measurement that's based on three other measurements, which means that each time you depend on more than one value, the inaccuracies start to build up. The total carbohydrates are not as accurate as you may think.
Fiber, on the other hand, is basically measured directly. It is measured through an enzymatic-gravimetric method, where a sample of food is treated with enzymes that simulates how we digest food in the small intestine. Digestible carbohydrates are removed. What remains is the non-digestible carbohydrates, which contains the fiber, protein and inorganic material called ash on most labs. The last two are subtracted from the weight to get the total dietary fiber.  Like the measurement for total carbs, the measurement for fiber is also not as accurate as you think.
Net carbs are generally the carbohydrates minus the fiber and sugar alcohols. These are the carbs in food that can be absorbed by the body and used for energy. To get the net carbs, you need to subtract the fiber and sugar alcohols from the total carbs.
We can’t break down most fibers, so they don’t have any impact on our blood sugar. It doesn't mean though that fiber is not processed by the body. The gut bacteria that we have in our system can use certain kinds of fiber for food and the byproduct of that can be used as fuel for the lining of our intestines.
That's why plant-based pastas like Miracle Noodles act as a prebiotic fiber, which means they are digested by your gut microbiome to help it grow. Fiber here is being processed in a sense, but when it comes to blood sugar and people on ketogenic diets, it's not going to have an effect.
How to Check Low-Carb Food Labels
When you check low carbohydrate foods like Miracle Noodles, you'll see something interesting on the label. On most of the plain noodles, you'll see that the total carbohydrates is less than the total fiber. On the label it says two grams of fiber, but with only one gram of total carbohydrate. You might be wondering how the amount of fiber, which is considered a carbohydrate, exceeds the number of total carbohydrates. Remember that you’re taking away the total fiber from the total carbohydrates to get the net carbs.
How is it possible for the total carbs on a food label to be less than the amount of total fiber? This is because when you get to the very low levels of low-carb foods, the inaccuracies of the lab tests done to measure carbs and fiber start to reveal themselves.
In this case, because they're measured in two different ways and the product is so dilute in terms of its carbohydrate and its fiber, even though there are two full grams of fiber in a serving, the product itself is 97% water. So, you're getting these dilute measurements being done and you're starting to see the inaccuracies mentioned above.
The inaccuracies are small enough to be insignificant. However, if you're on medically-indicated uses for ketogenic diet, like for seizures or for cancer, you have to be careful because you're dealing with inaccuracies of one or two grams in low-carb foods. I recommend doing blood tests at the very beginning to check if you’re in ketosis. Tools like Keto Mojo measure your blood ketones and glucose levels quickly.
You’ll be surprised to find that numerous blood tests of people who have been eating keto-certified foods revealed that they weren’t really in ketosis. That’s because when you get to these low-carb foods, the inaccuracies start to add up. The next time you see low-carb keto diet-friendly foods that have one or zero net carbs, consider looking at the raw ingredients. Go to the USDA website to check raw food ingredients. It tells you the carbohydrate and fiber content of the raw ingredient.
Know that you're dealing with some inaccuracies and you're probably getting one or two grams of some kind of carbohydrate, which are not reflected accurately on the food label.
When it comes to sugar alcohols, erythritol and xylitol are okay. Maltitol is not. You also have to watch out for sucralose as it damages your gut microbiome. But otherwise, those erythritol and xylitol aren't going to have an impact on your blood sugar.
Keep in mind that non-sugar sweeteners are also damaging your ability to perceive natural sweetness. They decrease your ability to appreciate low-sugar foods like blueberries and blackberries as your palette adjusts itself to these sweeteners like a thermostat. You won’t be able to appreciate natural foods anymore and crave more sweetened foods.
I hope these answer your questions about total carbs and net carbs. If you have more questions, please comment below or join and post on our Weight Loss Awakening Friendship group on Facebook.