Calculating Net Carbs: Mastering The Keto Sugar Alcohol Math

To calculate net carbs, subtract the grams of fibre and sugar alcohols from the total grams of carbohydrates. This is because fibre and sugar alcohols are not digested in the same way as other carbohydrates, and so do not impact blood sugar levels in the same way.

However, not all sugar alcohols are treated equally. Erythritol, for example, is not digested at all and so can be subtracted from the total number of carbs. Other sugar alcohols are only partially absorbed, and so only half of the grams should be subtracted from the total.

Calculating net carbs is particularly important for people with diabetes, as it can help them determine how much insulin they need. It is also useful for people following a keto diet, as it allows them to eat more fruits and vegetables, which are rich in fibre.

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 fibre is a type of carbohydrate that the body cannot digest.

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 calculation for net carbs is: Net carbs = Total carbs – Fibre – Sugar alcohol/2.

The Food and Drug Administration (FDA) does not recognise the term "net carbs" and recommends using total carbohydrates listed on nutrition labels instead.

Calculating net carbs in processed foods

To calculate net carbs in processed foods, it is important to understand the difference between net carbs and total carbs. Net carbs refer to the carbohydrates that are absorbed by the body and can be calculated by subtracting fibre and some sugar alcohols from the total amount of carbohydrates in a food product. Total carbs, on the other hand, include all types of carbohydrates in a food or meal, such as starches, dietary fibre, and sugars.

When calculating net carbs in processed foods, it is essential to read the nutrition label carefully. Look for the Total Carbohydrate section and note the number of total carbohydrates, fibre, and sugar alcohols. If your food product contains sugar alcohols, it is important to identify which type it is, as this will impact how much you subtract from the total carbohydrate amount.

The general rule for calculating net carbs in processed foods is to subtract the amount of fibre and half the amount of sugar alcohol from the total carbohydrates. This can be calculated using the following formula:

> Net carbs = Total carbohydrates - Fibre - (Sugar alcohols / 2)

However, it is important to note that not all sugar alcohols are treated equally. Erythritol, for example, can be completely subtracted from the total carbohydrates since it is not metabolized by the body. On the other hand, sugar alcohols like xylitol and sorbitol are only partially absorbed and metabolized, so only half of their amount is subtracted from the total carbohydrates.

Additionally, it is worth mentioning that food labels can vary between countries. In the USA and Canada, the amount of fibre is included in the total carbohydrate value, while in Australia, the fibre value is already subtracted from the total carbohydrates. Therefore, when calculating net carbs, it is crucial to consider the specific guidelines for your country.

The role of sugar alcohols

Sugar alcohols are becoming popular sugar substitutes and are rapidly replacing regular sugar in many keto and low-carb food products. They are neither sugar nor alcohol but a hybrid that creates a whole new type of carbohydrate compound. They are widely used in the food industry to reduce the amount of added sugar in low-carb or low-sugar products.

Sugar alcohols are often used as sugar substitutes in food products because they are difficult to digest and slow to metabolize. This is due to the presence of an alcohol group in the area typically occupied by a carbonyl group in sugars. This property also prevents polyols from being broken down by salivary amylases and fermented by bacteria found in plaque, both of which contribute to the production of acid and caries.

Sugar alcohols are commonly found in sugar-free chewing gum, medications, laxatives, and toothpaste. They are also added to foods that are marketed as "sugar-free" or "no sugar added". Erythritol, xylitol, mannitol, sorbitol, maltitol, mannitol, and glycerol are some of the most commonly used polyols in food products.

Sugar alcohols have several health benefits. They are typically lower in calories, and because they are harder to absorb and digest, they are a better option for controlling blood sugar levels. They are also beneficial for oral health as they inhibit the growth of harmful bacteria in the mouth and trigger a protective mechanism for oral health.

However, sugar alcohols may cause digestive issues such as bloating, diarrhea, flatulence, and stomach aches, especially if consumed in excess by those with digestive sensitivity. They may also inhibit gut bacteria, reducing the health benefits associated with a diverse range of healthy gut flora.

When it comes to the keto diet, sugar alcohols are considered keto-friendly as they have a much lower impact on blood sugar spikes due to being harder to digest. Erythritol is one of the best sugar alcohols to use as it has a glycemic index of zero and is well tolerated by the body. However, not all sugar alcohols are created equal, and some may have a more significant effect on blood sugar levels than others.

Overall, sugar alcohols play a crucial role in the keto diet as they provide a way to add sweetness to foods and beverages while still maintaining the low-carb requirements of the diet. They are a popular sugar alternative that can help individuals reduce their sugar intake and manage their blood sugar levels.

Net carbs for people with diabetes

People with diabetes have a problem with the insulin used to process blood glucose. When they eat foods with carbs, the carbs break down into glucose, which causes blood glucose levels to rise. Insulin is needed to keep these levels from rising too high.

The number of carbs a person with diabetes should eat depends on their body size, activity level, and appetite. It's important to eat the number of carbs that makes you feel best and that you can maintain in the long term.

The optimal amount of carbs varies by individual. Research suggests that many different levels of carb intake may help manage blood sugar.

How to Calculate Net Carbs

"Net carbs" refers to carbs that are absorbed by your body. To calculate the net carbs in whole foods, subtract the fibre from the total number of carbs.

The term "net carbs" is disputed among nutrition experts. The Food and Drug Administration (FDA) does not recognise the term and recommends using the total carbohydrates listed on nutrition labels.

Net carbs are sometimes referred to as digestible or impact carbs. They include both simple and complex carbs. Simple carbs are found in foods like fruits, vegetables, milk, sugar, honey, and syrup. Complex carbs are found in grains and starchy vegetables like potatoes.

When you eat a carb-containing food, most of the carbs are broken down into individual sugar units, which your body can absorb. However, some carbs can't be broken down, while others are only partially broken down and absorbed. These include fibre and sugar alcohols.

Because of this, most fibre and sugar alcohols can be subtracted from total carbs when calculating net carbs.

Calculating Net Carbs in Whole Foods

Whole foods contain naturally occurring fibre, so you can simply subtract the fibre from the total carbs to get the net carbs.

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 minus 13.5 grams of fibre equals 3.6 grams of net carbs.

Calculating Net Carbs in Processed Foods

To calculate net carbs in a packaged product, it's best to have as much information as possible. Generally speaking, half of the carbs from sugar alcohols can be subtracted from the total carbs listed on the nutrition label.

Erythritol is an exception. If it's the only sugar alcohol in the ingredients list, its carbs can be completely subtracted from the total carbs.

This value may be different than the number of net carbs stated on the product label, as many companies subtract all fibre and sugar alcohol carbs when calculating net carbs.

For example, an Atkins bar label states that it contains 3 grams of net carbs. However, when subtracting only half the carbs from sugar alcohols, the net carb value is 8.5 grams: 23 grams of total carbs minus 9 grams of fibre minus 11 grams of sugar alcohols (11 grams multiplied by 0.5 equals 5.5 grams) equals 8.5 grams of net carbs.

Sugar Alcohols

Sugar alcohols are often used as sugar substitutes in food products because they are difficult to digest and slow to metabolise. They are only partially absorbed in the small intestine, and there is variation among different types.

Researchers report that the small intestine absorbs 2–90% of sugar alcohols. However, some are only briefly absorbed into the bloodstream and then excreted in urine.

Sugar alcohols can have varying effects on blood sugar and insulin levels, although all are considerably lower than sugar.

• Erythritol: Glycemic index 0, insulin index 2
• Isomalt: Glycemic index 9, insulin index 6
• Maltitol: Glycemic index 35, insulin index 27
• Sorbitol: Glycemic index 9, insulin index 11
• Xylitol: Glycemic index 13, insulin index 11

Overall, sugar alcohols don't seem to have a major effect on blood sugar and insulin levels, but individual responses may vary, especially among those with diabetes or prediabetes.

Counting Carbs

Whether to count net or total carbs is a controversial topic within the low-carb community.

Counting net carbs encourages eating more whole foods and veggies, as these contain fibre. However, some people prefer to count total carb intake to reach ketosis more quickly or to avoid a keto plateau.

The key is to eat the number of carbs that allows you to achieve your health goals, no matter how you count them.

The pros and cons of counting net carbs

Counting net carbs can be a useful tool for managing your health and weight, but it is not without its pitfalls.

Pros of Counting Net Carbs

Counting net carbs can be a more sustainable way to track macros, and it encourages the consumption of whole foods and vegetables, which are rich in fibre. This method works well for most people.

Counting net carbs can also give you a better idea of what's in your food, and it encourages you to look closely at the carbohydrates you're eating, specifically in terms of sugars and starches.

Net carbs can be particularly useful for people with diabetes, as they can help manage blood sugar levels.

Cons of Counting Net Carbs

The term "net carbs" is disputed among nutrition experts, and the calculation can be confusing due to conflicting and outdated information. The Food and Drug Administration (FDA) does not recognise the term "net carbs" and instead recommends using the total carbohydrates listed on nutrition labels.

Not all fibre is the same, and insoluble fibre passes through your body undigested, so it is not counted towards your daily carb intake.

Sugar alcohols are also treated differently by the body, and some can raise your blood sugar levels. Sugar alcohols may also cause gastrointestinal problems for some people.

Finally, focusing on net carbs may cause you to overlook the number of calories in a product, which is an important consideration if your goal is weight loss.

Frequently asked questions