Understanding Net Carbs: Your Guide To Keto Success

Net carbs are the number of carbohydrates that are absorbed by your body. They are calculated by subtracting the fibre from the total number of carbs. This is important for those on the keto diet, as it helps them stay within their daily carb limit.

The keto diet is an ultra-low-carb diet, with most people aiming to eat fewer than 20 grams of carbs each day. This is because the keto diet recommends a low-carb, high-fat diet to help the body enter a metabolic state known as ketosis, where it begins to burn fat for energy instead of carbohydrates.

To calculate net carbs, you should first look at the nutrition label on your food packaging and note the total carbohydrates, fibre and sugar alcohols. Then, subtract the amount of fibre and half the amount of sugar alcohol from the total carbohydrates. This will give you the total net carbs.

It's important to note that not all sugar alcohols are treated equally when calculating net carbs. Sugar alcohols such as erythritol and xylitol have a negligible impact on blood sugar and can be counted as zero net carbs. However, sugar alcohols like maltitol, sorbitol, isomalt and glycerin do count towards net carbs and should be included in your calculations.

Calculating net carbs in whole foods

To calculate net carbs in whole foods, you need to subtract the fibre from the total number of carbs. This is because the body cannot fully digest most types of dietary fibre.

For example, a medium avocado contains 17.1 grams of total carbs, 13.5 grams of which is fibre. So, 17.1 grams of total carbs – 13.5 grams of fibre = 3.6 grams of net carbs.

The USDA Food Composition Databases provide complete nutrition information on thousands of foods, including carbs and fibre.

The formula for calculating net carbs is:

Net carbs = Total carbs – Fibre – Sugar alcohol / 2

It's important to note that the Food and Drug Administration (FDA) does not recognise the term "net carbs" and recommends using the total carbohydrates listed on nutrition labels.

Calculating net carbs in processed foods

To calculate net carbs in processed foods, you will need to look at the nutrition label on the product packaging.

First, note the number of total carbohydrates, fiber, and sugar alcohols. If you cannot find any sugar alcohols, don't worry—not all products contain them.

Next, use the following formula:

Net carbs = Total carbohydrates – Fiber – Sugar alcohol / 2

This formula will give you the net carb value, which may differ from the number stated on the product label, as many companies subtract all fiber and sugar alcohol carbs when calculating net carbs.

For example, let's say you have a product with 23 grams of total carbs, 9 grams of fiber, and 11 grams of sugar alcohols. Using the formula, you would calculate:

23 grams of total carbs – 9 grams of fiber – 11 grams sugar alcohols (11 grams X 0.5 = 5.5 grams) = 8.5 grams of net carbs.

It's important to note that Erythritol is an exception. If it's the only sugar alcohol listed in the ingredients, you can subtract its total amount from the total carbohydrates.

Additionally, the way food labels display nutrient information can vary between countries. For example, in the USA and Canada, the amount of fiber is included in the total carbohydrate value, while in Australia, it is subtracted from the total carbohydrates. Therefore, be sure to check how the information is presented on the labels in your country.

Why count net carbs?

Counting net carbs is important when following a keto diet because it helps you stay in a state of ketosis, which is the goal of the diet. Ketosis is a metabolic state in which your body burns fat for fuel instead of carbohydrates.

Net carbs are the number of carbohydrates that are absorbed by your body and impact your blood sugar levels and insulin response. They are calculated by subtracting dietary fibre and certain sugar alcohols from the total carbohydrate content of a food.

When following a keto diet, it is recommended to consume fewer than 20 grams of net carbs per day. This is because eating too many carbs can prevent you from reaching and maintaining ketosis. Counting net carbs allows you to be mindful of every gram of carbohydrates you consume and how your body responds to different foods.

Additionally, counting net carbs allows you to include some nutritious, fibre-rich fruits and vegetables in your diet without exceeding your daily keto carb goals. Net carbs are also useful for including sweet-tasting, "sugar-free" foods in your diet without impacting your net carb count. These foods use sugar alcohols to provide a sweet taste without affecting blood sugar levels.

However, it is important to note that not all sugar alcohols are truly low-carb, and consuming too much of them can have negative effects on your gut health. Therefore, it is crucial to read nutrition labels carefully and understand how different types of sugar alcohols impact your net carb count.

In conclusion, counting net carbs is essential for staying in ketosis and achieving the desired effects of a keto diet. It allows for flexibility in your diet while ensuring you consume an overall low amount of carbs that your body can absorb.

How to calculate net carbs

Net carbs refer to the number of carbohydrates that are absorbed by your body and have an impact on your blood sugar levels and insulin response. This is because some carbohydrates, like fiber and sugar alcohols, aren't digested by your body and, therefore, don't count towards your net carb intake.

To calculate net carbs, you can use the following formula:

Net Carbs = Total Carbohydrates – Fiber – Sugar Alcohol / 2

First, look at the nutrition label on the food packaging and note down the total carbohydrates, fiber, and sugar alcohols.

Then, subtract the amount of fiber and half the amount of sugar alcohol from the total carbohydrates. The result is the net carb count.

It's important to note that not all sugar alcohols are treated equally in this calculation. Sugar alcohols like erythritol and xylitol don't need to be included in your net carb count, while others like maltitol, sorbitol, isomalt, and glycerin should be counted as half a gram of carbs for every gram.

Additionally, the way nutrition labels are presented can vary depending on the country. In the USA and Canada, the total carbohydrates include fiber, while in Australia, the fiber is already deducted from the total carbohydrates. So, if you're calculating net carbs for a product purchased in Australia, you only need to subtract the sugar alcohols from the total carbohydrates.

Why the type of sugar alcohol matters

Sugar alcohols are a key component of the keto diet, as they are used to replace sugar in many keto-friendly products. They are neither sugar nor alcohol but a hybrid that creates a new type of carbohydrate compound. They are often used to sweeten sugar-free or diet products like chewing gum, yoghurts, ice cream, and protein bars.

However, not all sugar alcohols are created equal. Some are better for the keto diet than others, as they have varying effects on blood sugar and insulin levels. Here's why the type of sugar alcohol matters:

• Erythritol: Erythritol is a good keto-friendly option as it has a glycemic index of 0 and is well tolerated by the body. It is also not fermented by gut bacteria, so it doesn't cause digestive issues. It is commonly used as a sweetener in low-calorie foods.
• Xylitol: Xylitol is as sweet as regular sugar but has 40% fewer calories. It is one of the most common sugar alcohols and is often found in chewing gum, toothpaste, and mouthwash. It also has benefits for oral health, inhibiting the growth of harmful bacteria in the mouth.
• Sorbitol: Sorbitol is commercially produced from glucose and is 60% as sweet as sugar with about 60% of the calories. It is typically used in sugar-free candies, chewing gum, and frozen desserts.
• Maltitol: Maltitol has a lower glycemic index than sugar, but it is likely to have a more significant effect on blood sugar levels. It is processed from the sugar maltose and is 90% as sweet as sugar with almost half the calories. It is widely used in hard candies, chewing gum, chocolate, and baked goods.
• Isomalt: Isomalt is a mixture of two sugar alcohols, mannitol and sorbitol. It provides 50% fewer calories than sugar and is most commonly used to make sugar-free hard candies.

While most sugar alcohols are considered keto-friendly, it's important to note that they can cause digestive issues when consumed in large amounts. Additionally, due to their varying glycemic indexes, some sugar alcohols may be better choices than others for maintaining ketosis. As such, it's recommended to limit the intake of maltitol and choose sugar alternatives with lower GIs.

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