Understanding Net Carbs vs. Total Carbs on a Low Carb Diet

24 August 2025

If you're following a low-carb diet, you've likely come across the terms net carbs and total carbs. But what do they really mean? And why do some people count one over the other? It can get confusing, but don’t worry—we’re breaking it all down in simple terms so you can make the right choices for your diet.

Whether you're trying to lose weight, manage your blood sugar, or just feel better overall, understanding the difference between net carbs and total carbs can help you stay on track. Let’s get into it!

What Are Total Carbs?

Total carbohydrates, or total carbs, refer to the entire amount of carbohydrates in a food product. This includes:

- Sugar – The naturally occurring or added sugars in food.
- Fiber – The part of plant-based foods your body can’t fully digest.
- Starch – Complex carbs that break down into glucose in your body.

When you read a nutrition label, the number listed under "Total Carbohydrate" includes all of these components. But not all carbs affect your body the same way—which is where net carbs come in.

What Are Net Carbs?

Net carbs are the carbs that actually affect your blood sugar. This is important because fiber and certain sugar alcohols don’t raise blood sugar levels the way other carbs do.

The basic formula for calculating net carbs looks like this:

Net Carbs = Total Carbs – Fiber – Sugar Alcohols (if applicable)

By subtracting fiber and certain sugar alcohols, you get the net carbs—the carbs your body actually digests and converts into energy.

Let’s break it down with an example:

Example: Reading a Nutrition Label

Say you have a snack bar with the following nutrition facts:
- Total Carbohydrates: 22g
- Fiber: 10g
- Sugar Alcohols: 6g

Using the formula:
22g (Total Carbs) - 10g (Fiber) - 6g (Sugar Alcohols) = 6g Net Carbs

So although the snack bar has 22 grams of total carbs, only 6 grams of those will impact your blood sugar levels.

Why Do Net Carbs Matter on a Low-Carb Diet?

If you're on a low-carb diet like keto, Atkins, or just watching your carb intake, the number of carbs that affect blood sugar is what you really care about.

1. Net Carbs Help You Stay in Ketosis

On a keto diet, the goal is to keep your body in ketosis, where it burns fat for fuel instead of carbs. Since fiber and certain sugar alcohols don’t kick you out of ketosis, counting net carbs helps you track what actually matters.

2. Better Blood Sugar Control

For people with diabetes or insulin resistance, watching net carbs can be essential. Foods high in fiber don’t spike blood sugar the way other carbs do, which helps maintain steady energy levels and avoid crashes.

3. More Flexibility in Your Diet

If you focused only on total carbs, you'd eliminate a lot of healthy, fiber-rich foods like vegetables, nuts, and seeds. But counting net carbs allows you to enjoy these foods while still meeting your low-carb goals.

Should You Always Count Net Carbs?

Not necessarily. Some people prefer tracking total carbs instead of net carbs for a few reasons:

1. Not All Sugar Alcohols Are the Same

Some sugar alcohols, like maltitol, can still raise blood sugar levels, even though they’re often subtracted when calculating net carbs. If you consume a lot of processed low-carb treats, you might still notice blood sugar spikes.

2. Simplicity

For some, counting total carbs is just easier. It eliminates the guesswork of which types of fiber and sugar alcohols to subtract.

3. More Effective for Weight Loss

If you’re not losing weight on a low-carb diet, tracking total carbs instead of net carbs can help. Even fiber-rich foods still contain calories, and going overboard can stall progress.

What About Fiber? Does It Really Not Count?

Dietary fiber is a type of carbohydrate, but your body doesn’t digest it the way it does sugar or starch.

- Insoluble fiber passes through your system without raising blood sugar at all.
- Soluble fiber is partially broken down, but generally has little impact on blood sugar.

Because most fiber doesn’t get absorbed, it’s usually subtracted when calculating net carbs. However, if you’re eating high amounts of processed fiber (like chicory root fiber), it may still have some effect on your digestion and metabolism.

What About Sugar Alcohols?

Sugar alcohols are sweeteners often used in sugar-free or low-carb products. Some common ones include:

| Sugar Alcohol | Affects Blood Sugar? | Should You Subtract It? |
|--------------|----------------------|----------------------|
| Erythritol | No | Yes (fully) |
| Xylitol | Slightly | Partially |
| Maltitol | Yes | No (partially affects blood sugar) |
| Sorbitol | Yes | No |

Not all sugar alcohols behave the same way. Erythritol, for example, doesn’t impact blood sugar, so it’s usually safe to subtract from total carbs. But others, like maltitol, have a higher glycemic index and should be counted at least partially.

Best Foods for Counting Net Carbs

If you’re focusing on net carbs, here are some great low-net-carb options:

Low-Net-Carb Vegetables

- Spinach
- Kale
- Broccoli
- Cauliflower
- Zucchini

Low-Net-Carb Fruits

- Avocados
- Berries (strawberries, raspberries, blackberries)
- Olives

Low-Net-Carb Nuts & Seeds

- Almonds
- Walnuts
- Chia seeds
- Flaxseeds

Other Good Choices

- Eggs
- Meat & Fish
- Cheese
- Butter & Healthy Oils (coconut oil, olive oil)

Foods That Can Be Tricky

Even if a label says "low-carb", you should still check if the net carb count makes sense. Some processed foods use hidden sugars or sugar alcohols that still impact blood sugar.

Watch Out For These:

- Low-carb bars with maltitol
- Sugar-free candy with sorbitol
- Fiber-enriched processed snacks
- Low-carb bread (some have hidden starches)

Always read nutrition labels and do the math yourself—some brands try to market something as "keto-friendly" when it’s really not.

Final Thoughts

So, should you count net carbs or total carbs? It depends on your personal health goals.

- Go with net carbs if you're following keto and want to stay in ketosis while including fiber-rich foods.
- Stick with total carbs if you prefer a simple approach, have trouble losing weight, or react to sugar alcohols.

At the end of the day, the best diet is the one that works for you. Whether you're counting net carbs or total carbs, the most important thing is that you're mindful of what you're eating.

Want to get the most out of your low-carb journey? Start by focusing on whole, nutrient-dense foods and avoiding overly processed "low-carb" products that might not be as healthy as they seem.