Staying Under The Keto Carb Limit: How Many?

The ketogenic diet, commonly known as the keto diet, is a popular low-carb, high-fat diet used for weight loss and managing certain health conditions. To stay in ketosis, the body's fat-burning state, a person should consume up to 50 grams of carbohydrates per day, with some sources suggesting that 20-30 grams is optimal for ketosis. This amount can vary depending on individual factors such as activity level, weight goals, age, gender, and health conditions. The keto diet involves not only limiting carbs but also moderating protein intake, as excess protein can prevent ketosis. To calculate net carbs, people can subtract dietary fibre and half of the sugar alcohols from the total carbohydrate amount.

Net carbs vs total carbs

To achieve ketosis, the ketogenic diet typically limits daily net carb intake to 20-50 grams. However, the specific amount of carbs can vary depending on individual needs, with some people needing to stay under 20-30 grams to reach ketosis.

Now, what are net carbs, and how are they different from total carbs?

Net carbs refer to the carbohydrates in food that can be absorbed and used by the body for energy. These are the carbs that are counted when following a ketogenic diet. To calculate net carbs, you subtract the amount of fibre and sugar alcohols from the total amount of carbohydrates. Net carbs are an important consideration on the keto diet because they are the ones that impact your blood sugar levels and energy.

On the other hand, total carbs include all types of carbohydrates, even those that are not fully absorbed by the body, such as fibre and sugar alcohols. Total carbs are simply the sum of all the carbs in a food product, as listed on nutrition labels.

The distinction between net carbs and total carbs is important because it helps determine the number of carbs that will actually impact your body and energy levels. Net carbs give a more accurate reflection of your keto progress as they represent the carbs that are absorbed and used by the body.

While total carbs may be higher, focusing on net carbs ensures you're not denying your body essential fibre, which is important for proper bodily functions. Additionally, by tracking net carbs, you can make sure you're staying within the recommended carb limits for ketosis, which is crucial for the success of the keto diet.

How to calculate net carbs

Net carbs are an important part of the keto diet, and it's essential to know how to calculate them to stay in ketosis. Net carbs refer to the carbohydrates that are absorbed by your body and are calculated by subtracting indigestible carbs from the total carb content.

To calculate net carbs, you need to determine the total carb content of a food item. This includes all carbohydrates, such as sugar, fibre, and starches. Once you have the total carb content, you can then subtract the indigestible carbs, which include:

• Fibre: Fibre is a complex carb that the body cannot fully break down. By subtracting the fibre content from the total carbs, you get the net carbs.
• Sugar Alcohols: These are used to sweeten low-carb foods, and while they are similar to fibre in how the body processes them, they are not all equal. Erythritol, for example, can be completely subtracted from the total carbs, while other sugar alcohols should be halved before subtracting.

Net Carbs = Total Carbs - Fibre - Half of Sugar Alcohols (unless Erythritol, then subtract the total)

For example, if a food item has 20g of total carbs, 8g of fibre, and 5g of sugar alcohols, the net carbs would be:

20g - 8g - 2.5g = 9.5g of net carbs.

It's important to note that the Food and Drug Administration (FDA) does not recognise the term "net carbs" and recommends using total carbohydrates listed on nutrition labels. Additionally, the keto diet typically aims for 50 grams or less of net carbs per day, and sometimes as low as 20 grams, depending on individual needs.

By understanding and calculating net carbs, you can better manage your blood sugar, weight, and overall health while on the keto diet.

How to calculate carbs

To calculate your net carb intake, you need to subtract the amount of dietary fibre and half the amount of sugar alcohols from the total amount of carbohydrates. This is because your body does not fully digest these substances, and they do not impact your blood sugar.

> NET CARBS = TOTAL CARBS – FIBRE – SUGAR ALCOHOLS & ALLULOSE

For example, a keto pancake with 13 grams of total carbohydrates, 9 grams of fibre, 2 grams of erythritol, and 1 gram of allulose would have 1 gram of net carbohydrates.

You can also use a net carb calculator, which is available online.

It is important to note that the recommended net carb intake for keto dieters is below 50 grams per day, with some sources recommending 20-25 grams per day to reach the fat-burning state of ketosis quickly.

How to determine if you're in ketosis

To determine if you're in ketosis, there are several methods and indicators to look out for. Ketosis is a metabolic state where the body uses stored fat as its primary energy source instead of carbohydrates. This state is achieved by following a low-carb diet, typically under 50 grams of carbs per day, and sometimes as low as 20 grams. Here are some ways to know if you're in ketosis:

Monitor Ketone Levels

The most reliable way to determine if you're in ketosis is by measuring your blood ketone levels using a specialized meter. This method is commonly used in research studies and involves testing your blood by pricking your finger. According to experts, nutritional ketosis is defined as having blood ketone levels of 0.5 millimoles per liter or higher.

Bad Breath

Bad breath, often described as fruity or sweet, is a common side effect of ketosis. This is caused by the presence of acetone, a ketone that exits the body through the breath and urine. Brushing your teeth several times a day or using sugar-free gum may help mask the odour.

Weight Loss

Ketosis is often associated with weight loss due to the reduction of the body's glycogen and water stores. However, initial weight loss is typically a result of losing water weight, and true fat loss may take several weeks.

Increased Focus and Energy

Long-term keto dieters often report experiencing increased focus and energy levels. This is because ketones provide an extremely potent fuel source for the brain. However, in the initial stages of the diet, it is common to feel tired and weak as the body adapts to burning fat instead of carbohydrates.

Appetite Suppression

Many people on a keto diet experience a decrease in hunger. This may be due to alterations in hunger hormones and increased protein intake. The ketones themselves may also affect the brain, reducing appetite.

Short-Term Fatigue and Decreased Performance

Starting a keto diet can lead to well-known side effects such as weakness, fatigue, and a decrease in exercise performance. These are often caused by the reduction in glycogen stores, which are the primary fuel source for high-intensity exercise. However, after several weeks, keto dieters typically report a return to normal performance and an increased ability to burn fat during exercise.

Digestive Issues

Making any dietary changes can increase the risk of digestive issues such as constipation and diarrhoea. This is also common when starting a keto diet, and ensuring adequate fluid intake and consuming fibre-rich foods can help alleviate these issues.

Sleep Disturbances

The keto diet may initially disrupt sleep, causing insomnia or nighttime waking. However, these effects usually improve within a few weeks, and long-term keto dieters often report improved sleep.

While these indicators can give you a good idea of whether you're in ketosis, the most accurate way to determine ketosis is by monitoring your ketone levels through blood, breath, or urine tests. Additionally, staying consistent with your keto diet and tracking your carb intake are crucial for maintaining ketosis.

Factors influencing your daily carb limit

Several factors determine the number of carbs you should consume each day while on a keto diet. Here are some key considerations:

Activity Level

If you are highly active, you may need to consume more carbs to meet your energy requirements. Carbs are a vital source of energy, and if your body is not getting enough from fats, it may need to turn to carbs to fuel your activities.

Weight Goals

Those aiming for weight loss may need to adhere to a stricter carb limit. The keto diet is often used as a tool for weight management, and reducing carb intake is crucial to achieving ketosis and promoting fat burning.

Age and Gender

The number of carbs needed can vary depending on age and gender. Generally, men require more calories and, by extension, more carbs than women. Age also plays a role, as metabolic rates tend to decrease with age, influencing carb requirements.

Health Conditions

Certain health conditions may require modifications to your carb intake. For example, those with diabetes or prediabetes may need to carefully monitor their carb consumption to manage blood sugar levels effectively.

Dietary Preferences

Dietary choices such as vegetarianism or veganism can impact your carb intake. These diets often rely more heavily on carbohydrate sources for energy, which may need to be adjusted to fit within the keto guidelines.

Individual Needs

The number of carbs you consume on keto can vary from 20 to 50 grams per day, depending on your individual needs and goals. Some people may find they need to stay at the lower end of this range to achieve optimal ketosis, while others can tolerate a slightly higher carb intake.

It is important to remember that the keto diet is a significant departure from a standard diet and may not be suitable for everyone. Consulting a healthcare professional or dietitian is crucial to determine if keto is right for you and to personalise your daily carb limit accordingly.

Frequently asked questions