What is Considered to be an Extreme Low Carb Diet?

An extreme low carb diet would generally be considered to be a restrictive Keto diet with under 30 grams of carbs a day, or a “no-carb” diet with even fewer than 20 grams of carbs a day.

What are Carbs?

Carbs (carbohydrates) are one of the three main macronutrients. Macronutrients are the nutrients that your body needs in large quantities to survive. The other two macronutrients are protein, and fat. Carbs are made of sugar, starches, and fibers. The digestive system breaks carbs down into glucose, or blood sugar. The bloodstream absorbs the glucose and uses it as energy to fuel the body. There are different types of carbs. The two main types are simple carbs, and complex carbs. Both types of carbs give your body energy. Simple carbs provide shorter bursts of energy, while complex carbs take longer for the body to break down, and are a longer lasting energy source. Simple carbs are found in things like table sugar, and fruit. Complex carbs are found in things like whole grains, and legumes.

What is a Low Carb Diet?

Low carb diets involve cutting the amount of carbs that you consume on a daily basis. Typically anything under about 130 grams of carbs a day is considered to be low carb. However, low carb diets can go as low as 50, or even 20 or fewer, grams of carbs a day. This is in the keto diet range. On a low carb diet, to make up for eating fewer carbs, you generally make it up with more fat, more protein, or both. There are many different variations of low carb diets, including some commercial ones such as Atkins or the south beach diet.

The Keto Diet as Extreme Low Carb Diet

Keto diets generally involve consuming between 50 and 20 grams of carbs per day. The keto diet is very similar to other types of low carb diets. It is very low carb, and high fat. It involves drastically cutting the body’s carb intake, and replacing it with fat. When you reduce your intake of carbs by this much, it puts your body into the state of ketosis. When ketosis occurs, your body becomes incredibly efficient at burning fat for energy. The body turns fat into ketones in the liver, which can then supply energy for the brain. Fat is then turned into ketones in the liver, which can then supply energy for the brain. 

There is no exact limit for what extreme carb means. However, I believe that Keto can fall within this carb range. I would say if you’re on the upper limit of Keto, around 50 grams of carbs, that is very low but not yet extreme, but if you’re on the lower limits of Keto, say 20-30 grams of carbs a day, that is pretty extreme. 

There is actually a type of Atkins diet called Atkins 20, and it is an extreme low carb diet run by Atkins. There are 4 phases of Atkins 20. It starts out in Phase 1, the most restrictive phase with only 20-25 grams of carbs a day, and you slowly increase your carb intake to 100 grams of carbs a day eventually in phase 4. 

Phase 1 of Atkins 20 really is quite extreme. In this phase you can only consume foundation vegetables, proteins, healthy fats, cheeses, and nuts and seeds. You are NOT able to consume any fruits, even berries which are considered quite low carb. You cannot consume cottage cheese or yogurt, legumes, tomato juice, any whole grains, or starchy vegetables. As one might imagine, being this restrictive is extremely difficult over the long term. That is why it is not recommended for the long term, and the diet becomes less stringent over time. Eventually in Phase 4, you can consume moderate amounts of even whole grains, and starchy vegetables.

No Carb Diet as Extreme Low Carb

Even more extreme than the 20 gram Keto diet is the “No Carb” diet. The no-carb diet is the most extreme form of low carb diet possible. This type of diet eliminates almost all carbs, including fruits, whole grains, and most vegetables. However, it should be said that completely eliminating carbs in this manner is highly restrictive, and probably unnecessary. A no-carb diet can be even more restrictive than the standard Keto diet.

No-carb diets eliminate carbs as much as humanly possible. You only eat foods that contain primarily protein or fat, such as meats, fish, eggs, cheese, oil, and butter. You eliminate all whole and refined grains, baked goods, all fruits, yogurt, milk, beans, legumes, bread, pasta, and starchy vegetables like corn and peas. If you’re more stringent you probably won’t be eating nuts and seeds. If you are a bit less stringent, you may be eating some nuts and seeds, as well as high fat low net carb foods such as avocado and coconut. 

Low carb diets in general do have a lot of health benefits. They may benefit heart health, lead to better blood sugar control, and lower blood pressure. They may reduce belly fat and lower the risk of metabolic syndrome. 

However, due to how extreme the “no-carb” diet is, there are also downsides. Since fruits, most vegetables, and beans and whole grains are restricted, it can be very low in fiber, and lead to constipation and low energy. It may lack some nutrients and may not provide enough vitamins and minerals, such as potassium, B vitamins, and Vitamin C, which are found in fruits, vegetables, and other plant foods. You may have deficiencies in sodium and potassium over time. And the long term effects of a diet this low in carbs are widely unknown. There are very few studies on no-carb diets in the long run, so following it for a long period of time could have severe health consequences.

Looking to lose weight or get in shape, and want help doing it? We work with a variety of amazing programs who we can share your answers with, matching you up with the best one for you, many of whom offer private or group coaching. If you would like to receive a quote about a personalized weight loss or fitness program please fill out this brief, 30 second form:

Name *

Phone *

Email Address *

Are You Interested in Weight Loss, Fitness, or both? *

What's the Maximum You Would Spend on Amazing Private Coaching That Helped You To Lose Tons Of Weight? *

Send Message