Subtracting Carbs: Keto Diet's Essential Math For Weight Loss

When following a ketogenic diet, it is important to understand the difference between net carbs and total carbs. Net carbs refer to the number of carbohydrates that are absorbed by your body, while total carbs simply refer to the total number of carbohydrates in a food item. To calculate net carbs, you subtract the fibre and certain sugar alcohols from the total number of carbs. This is because fibre and some sugar alcohols cannot be broken down and absorbed by the body, and therefore do not impact blood sugar levels. However, not all sugar alcohols can be subtracted from total carbs, as some do impact blood sugar and insulin levels. For example, erythritol, a sugar alcohol, does not raise blood sugar and insulin levels, so it can be subtracted. In contrast, sugar alcohols such as sorbitol, xylitol, and maltitol do raise blood sugar and insulin, so they cannot be subtracted.

Fibre can be subtracted from total carbs

When it comes to the keto diet, it's important to understand the difference between total carbs and net carbs. Net carbs refer to the carbohydrates that are absorbed by your body and have an impact on your blood sugar levels. To calculate net carbs, you subtract the fibre and certain sugar alcohols from the total number of carbs.

Fibre is a type of carbohydrate that cannot be broken down and absorbed by the digestive tract. Instead, it passes through the system until it reaches the colon, where it is either fermented by bacteria or eliminated in faeces, depending on the type. Insoluble fibre, for example, creates bulkier stools and can help prevent constipation, while soluble fibre has various health benefits.

When calculating net carbs, it is recommended to subtract only the fibre that naturally occurs in whole foods. This is because your body may respond differently to added fibre in keto and low-carb products. Additionally, some sugar alcohols, such as erythritol, can also be subtracted from the total carb count as they have minimal impact on blood glucose and ketone levels.

By subtracting fibre and certain sugar alcohols from the total carbs, you can more accurately determine your net carb intake and ensure you stay within your desired carb limit. This is particularly important for those following a keto diet, as consuming too many carbs can hinder ketosis, which is the goal of the diet.

It is worth noting that the term "net carbs" is not officially recognised by the Food and Drug Administration (FDA), which recommends using the total carbohydrates listed on nutrition labels. However, by understanding and calculating net carbs, individuals can make more informed choices about their carbohydrate intake, especially when trying to maintain a state of ketosis.

Erythritol can be subtracted from total carbs

Erythritol is a sugar alcohol, or 'polyol', which is a subgroup of carbohydrates. It is often used as a sugar substitute in food products because it is difficult to digest and slow to metabolise.

When following a keto diet, it is important to calculate net carbs to ensure you do not exceed your daily limit and to stay in ketosis. Net carbs are the carbohydrates in food that you digest and use for energy. They are calculated by subtracting dietary fibre and certain sugar alcohols from the total carbohydrates in a food product.

Erythritol is one of the few sugar alcohols that can be fully subtracted from the total carbohydrates since it is not metabolised. This is because it is fully absorbed in the small intestine and is then excreted as is in the urine. It therefore has little impact on blood sugar levels compared to other sugar alcohols.

Other sugar alcohols, such as xylitol, sorbitol, and maltitol, can only be partially subtracted from total carbohydrates. This is because they are either partially or incompletely absorbed and metabolised by the body, and so they can still impact blood sugar levels.

Therefore, erythritol can be subtracted from total carbs on keto.

Mannitol can be subtracted from total carbs

When following a keto diet, it is important to keep track of your net carbs, which are the carbohydrates that your body uses for energy. Net carbs can be calculated by subtracting dietary fibre and certain sugar alcohols from the total carbohydrate content of a food item.

Mannitol is a type of sugar alcohol that is widely used in the food and pharmaceutical industries. It is a polyol, which is a low-digestible carbohydrate that is only partially absorbed by the small intestine and not metabolised. This means that mannitol can be subtracted from total carbs when calculating net carbs.

Mannitol is about 50% as sweet as sucrose and has a desirable cooling effect that can be used to mask bitter tastes. It is also non-cariogenic and has a low caloric content, making it suitable for ingestion by people with diabetes. It is resistant to metabolism by oral bacteria and does not increase the acidity of the mouth, which means that it does not contribute to the formation of dental caries.

The use of mannitol in food is permitted by FDA food additive regulations, and it has been deemed safe by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives. However, it is important to note that consuming more than 20 grams of mannitol per day may cause a laxative effect in some individuals.

Sorbitol can be partially subtracted from total carbs

When following a keto diet, it's important to keep track of your net carbs, which are the carbohydrates that your body uses for energy. Net carbs can be calculated by subtracting dietary fibre and certain sugar alcohols from the total carbohydrate content of a food item. This is because your body cannot completely break down and absorb some types of carbs like fibre and sugar alcohols.

Sorbitol is a type of carbohydrate called a sugar alcohol or polyol. It is about 60% as sweet as sugar and contains about one-third fewer calories. It occurs naturally in berries and fruits like apples and blackberries and is also commercially produced from glucose. It is recognised as safe by global health authorities, including the World Health Organization, the European Union, Australia, Canada, Japan, and the US Food and Drug Administration (FDA).

Sorbitol is slowly and incompletely absorbed in the small intestine. The remaining sorbitol that is not absorbed continues to the large intestine, where its metabolism yields fewer calories. This means that sorbitol consumption reduces insulin secretion and helps keep blood glucose levels lower.

However, sorbitol, like other sugar alcohols, can cause gastrointestinal discomfort when consumed in excessive amounts. This is because sorbitol is fermented by bacteria in the large intestine, which can lead to bloating, gas, and diarrhoea. As a result, the FDA requires a warning label on products containing sorbitol about potential laxative effects.

When calculating net carbs, only 25% of sorbitol is absorbed in the small intestine, while the rest is fermented by bacteria. The small amount of sorbitol that is absorbed can still impact blood sugar levels because it is fully metabolised, although very slowly. Therefore, when calculating net carbs, it is reasonable to deduct 75% of the total grams of sorbitol from the total carbohydrates.

For example, if a food product contains a total of 20 grams of carbohydrates, and 10 grams come from sorbitol, then you would deduct 7.5 grams from the total carbohydrate content, resulting in about 12.5 or 13 grams of net carbohydrates.

In summary, sorbitol can be partially subtracted from total carbs when calculating net carbs for a keto diet. By taking into account the amount of sorbitol that is absorbed and metabolised, you can more accurately determine the net carb content of a food product and make more informed decisions about your carbohydrate intake.

Xylitol can be partially subtracted from total carbs

Xylitol is a naturally occurring sugar alcohol found in plant material, particularly in a wide array of fruits and vegetables. It is also present in small amounts in the human body. Commercially, xylitol is produced from either hardwood trees or corn cobs.

Xylitol is as sweet as regular sugar but has a low glycemic index of 7, compared to 100 for glucose and 65 for sucrose. This means it has minimal impact on blood glucose and insulin levels, which is beneficial for those on a keto diet.

When calculating net carbs, you can subtract the fibre and sugar alcohols from the total carbohydrates. Xylitol is a sugar alcohol, so it can be partially subtracted from the total carbs. However, it is important to note that xylitol does contain about 0.4g of net carbs per gram, which is significantly lower than regular sugar but still contributes to the total carb count.

Xylitol is an excellent alternative for those seeking to reduce their carb intake while maintaining the sweetness of regular sugar. It is a popular choice for those following a keto diet due to its low carb content and its positive impact on dental health.

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