Calculating Carbs For Keto: A Step-By-Step Guide

The keto diet is a popular low-carb diet that involves reducing your carbohydrate intake to fewer than 20 grams of carbs per day. Net carbs are the number of carbohydrates that are absorbed by your body and impact your blood sugar levels and insulin response. To calculate net carbs, you need to subtract dietary fibre and sugar alcohols from the total carb content. This is because fibre and sugar alcohols aren't digested or absorbed by the body and therefore do not impact blood sugar levels.

Net carbs vs. total carbs

The keto diet is a low-carb, high-fat diet. It involves taking an extremely low amount of carbohydrates and substituting them with fat to stimulate the body's fat-burning processes. The keto diet aims to bring the body into a state of ketosis, where it uses fat for energy instead of carbs.

Net carbs and total carbs are two different ways of measuring carbohydrate intake. This article will explain the difference between the two and provide guidance on how to calculate net carbs.

Total Carbs

Total carbs include all types of carbohydrates, including starches, dietary fibre, and sugars. On a nutrition label, you can typically find a breakdown of these components:

• Sugars, such as glucose or fructose, including a separate line for added sugars (those not naturally occurring in the food).
• Fibre, which the body cannot digest but may feed good gut bacteria.
• Sugar alcohols (more on these below).
• Starches, which convert to glucose during digestion.

Net Carbs

Net carbs refer to the total amount of digestible carbohydrates in a food product or meal. They are calculated by subtracting the amount of fibre and some sugar alcohols from the total carb count. Net carbs are important on the keto diet because the body does not absorb or digest fibre and sugar alcohols, so they are not counted.

The formula for calculating net carbs is as follows:

Net Carbs = Total Carbs – Fibre – Sugar Alcohols

For example, if a food product has 20 grams of total carbs, 8 grams of fibre, and 5 grams of sugar alcohols, the net carb count would be 7 grams (20 grams – 8 grams – 5 grams = 7 grams).

It is important to note that not all sugar alcohols are treated equally in this calculation. Erythritol, for instance, is not digested into glucose at all, so the total amount can be subtracted from the total carb count. For other sugar alcohols, only half the amount is typically subtracted.

Counting net carbs provides a truer sense of how many carbs the body is using for energy, which is key on the keto diet. It also allows for the inclusion of more nutritious, fibre-rich fruits and vegetables in the diet without exceeding daily keto carb goals.

However, it is worth noting that the concept of net carbs is not universally recognised by scientists and healthcare professionals, and there is ongoing debate about the benefits of calculating net carbs versus total carbs.

How to calculate net carbs

Net carbs are the number of carbohydrates that are absorbed by your body and used for energy. They are also referred to as digestible or impact carbs. Net carbs are calculated by subtracting the number of grams of fibre and sugar alcohols from the total number of carbohydrates.

The ketogenic (keto) diet is a low-carb diet that puts the body into a state of ketosis. This means that instead of burning carbohydrates for energy, the body burns fat. To stay in ketosis, a person can consume up to 50 grams of net carbs per day.

To calculate net carbs, you need to know the total number of carbohydrates, the number of grams of fibre, and the number of sugar alcohols.

Step 1: Determine the total carb content by reading the nutrition label.

Step 2: Subtract the grams of fibre and sugar alcohols from the total number of carbohydrates. The remaining amount is the total net carb count.

Additional Considerations

• Always read nutrition labels.
• Avoid highly insulinogenic carbs, which are higher on the glycemic index (GI) and more likely to spike insulin levels.
• Not all sugar alcohols are truly carb-free, so be mindful of your intake.

Why count net carbs?

Counting net carbs is important when following a keto diet because it helps you stay within your daily carb limit. Net carbs are the number of carbohydrates that are actually absorbed by your body and impact your blood sugar levels and insulin response. This is because fiber and sugar alcohols aren't digested by the body and therefore aren't counted on a keto diet.

By only counting net carbs, you get a truer sense of how many carbs your body is using for energy, which is key when following a keto diet. This also allows you to include more nutritious, fiber-rich fruits and vegetables in your diet without going over your daily keto carb goals.

Net carbs are calculated by taking the total carbohydrates and subtracting the grams of fiber and sugar alcohols. This calculation isn't perfect, as there are variations in the types of fiber and sugar alcohols, but it's currently the best way to estimate how many digestible carbs you're consuming.

Counting net carbs is particularly important on ultra-low-carb diets like keto, where the recommended carb intake is less than 20 grams per day. This can be challenging to achieve, but counting net carbs allows for some additional healthy carbohydrates to be included in your meals.

Sugar and sugar alcohol

Sugar alcohols are often used as a sugar substitute and are commonly found in products labelled as ""sugar-free". They are also found naturally in certain fruits and vegetables. Sugar alcohols have a similar chemical structure to glucose but with an added hydroxyl group. This means they are digested differently to glucose and have a lower caloric content.

Sugar alcohols are not easily digestible, so they are considered to be a better option for those looking to control their blood sugar levels. However, they can cause digestive issues such as bloating, flatulence, and stomach aches.

Some common sugar alcohols include:

• Erythritol
• Xylitol
• Maltitol
• Sorbitol
• Isomalt
• Mannitol
• Glycerol

When calculating net carbs, sugar alcohols are usually subtracted from the total carb count. However, this is not always the case and depends on the type of sugar alcohol. For example, erythritol and allulose can be counted as 0 net carbs, whereas other sugar alcohols are only halved when calculating net carbs.

Why is calculating net carbs important?

Net carbs are an important consideration for those following a keto diet because they provide a more accurate representation of the number of carbohydrates that are actually absorbed by the body and used for energy. This is because net carbs do not take into account fibre and some sugar alcohols, which are not fully digested or metabolised by the body and therefore do not impact blood sugar levels.

Calculating net carbs is simple: you just need to subtract the grams of fibre and sugar alcohols from the total number of carbohydrates. This can be done using a net carb calculator or by looking at the nutritional information on food labels.

For those on a keto diet, focusing on net carbs allows for the inclusion of more nutritious, fibre-rich fruits and vegetables in meals. It also enables people to enjoy sweet-tasting foods that are technically "sugar-free", as sugar alcohols are not counted towards net carb intake.

However, it is important to note that the term "net carbs" is not recognised by the FDA, which recommends using total carbohydrates listed on nutrition labels instead. Additionally, not all sugar alcohols are treated equally when calculating net carbs, and individual responses to different types of sugar alcohols may vary.

Frequently asked questions