Does Ketosis Help Burn Fat?

Ketosis can help burn fat through the conversion of lipids to glucose in the liver for energy. Keep reading to learn more.
Does Ketosis Help Burn Fat?
Saúl Sánchez

Written and verified by el nutricionista Saúl Sánchez.

Last update: 27 May, 2023

Ketosis is a physiological process through which the body mobilizes and oxidizes fat in order to generate energy. Therefore, it can be understood that it’s a mechanism that can help improve the state of body composition. In the following article, we’re going to check if this is really the case and if the ketogenic diet can contribute to reducing the adipose percentage of the human body. In other words, does ketosis help us burn fat?

First of all, it must be mentioned that, regardless of the type of diet proposed, it’s essential to ensure that the essential nutrient requirements are covered throughout the day. Otherwise, over the years, a series of inefficiencies could be experienced that would end with the genesis of chronic and complex diseases.

When does ketosis occur?

Ketosis normally begins when dietary carbohydrates in the blood are depleted. If the contribution of sugars is limited, there comes a time when the body has to start producing glucose from other substrates to keep blood glucose levels stable. Otherwise, a hypoglycemic situation would develop that could be fatal. The human body has a series of mechanisms to avoid this type of situation.

Therefore, when the contribution of carbohydrates in the diet isn’t high, the liver begins to generate sugars from amino acids and fatty acids. In this way, glucose will be supplied to the tissues, while the brain changes its main energy substrate for ketone bodies. Thanks to this adaptation, physiological functions can be carried out efficiently despite dietary restrictions.

In fact, ketosis could be efficient to treat certain diseases that occur with inefficient glucose management, such as those of a metabolic type. This is demonstrated by a study published in the Journal of Medical Internet Research . Proposing a low intake of carbohydrates in the diet could lead to better glycemic control in patients with type 2 diabetes.

Of course, before establishing a treatment of this type, it’s advisable to consult a specialist. Not only must individual tolerance be checked, but it’s key to apply the procedure progressively to avoid uncontrollability in the first moments that could put health at risk. However, if executed correctly, it appears that the benefits far outweigh the risks.

Ketosis to burn fat

Ketosis and fat are related in several ways
The option of resorting to ketosis to improve the state of body composition has become popular in recent years due to the rise of the ketogenic diet.

Based on what has been said, it could be assumed that entering a state of ketosis would be ideal in order to burn fat and improve body composition. However, experts disagree on the matter.

It’s true that ketogenic diets have proven to be efficient in reducing the body’s adipose percentage, but they don’t always present better results than other types of low-calorie approaches.

There are really several factors that can condition weight loss. It’s clear that in conditions of metabolic efficiency, one of the key factors will be the energy deficit. Eating fewer calories than are expended will lead to the mobilization and oxidation of accumulated fat, which will have a positive impact on the state of body composition. However, this scenario doesn’t always occur.

On many occasions, it starts from a situation of inefficiency at the metabolic level. There’s resistance to insulin, so the use of energy substrates by the body isn’t optimal. This leads to fat not being mobilized efficiently. To correct this situation, it would be necessary to act by increasing the level of physical activity and muscle mass. Proposing a type of ketogenic diet could be useful.

Even a less aggressive mechanism may suffice. Intermittent fasting itself is capable of increasing insulin sensitivity, thus promoting weight loss. This is evidenced by research published in the journal The Proceedings of the Nutrition Society.

In this way, little by little, it’ll be easier to use fat as the main energy substrate. This is mainly because, after fasting, fasting glucose levels tend to drop.

How to achieve a state of ketosis?

To achieve a state of ketosis, two different pathways can be launched. The first of these consists of fasting, that is, spending a certain number of hours without eating. Little by little, the availability of dietary carbohydrates as an energy substrate will be reduced, so the liver will have to compensate by producing glucose from the amino acids and fatty acids present in the body.

Of course, you have to be careful. Up to the first 24 hours of fasting, the effects are more positive than negative in many cases. However, once this barrier is overcome, emphasis begins to be placed on the destruction of muscle proteins to obtain amino acids that serve to satisfy energy demands. This could translate into muscle catabolism, something that’s not recommended in the medium term.

Another alternative that exists in order to enter a state of ketosis is the application of a ketogenic diet, that is, a diet that’s restrictive in terms of carbohydrates. Different guidelines can be considered depending on the maximum amount of sugars that is allowed.

Normally, the most lax versions allow 50 grams of carbohydrates per day, mainly from vegetables. The most restrictive options contemplate only a consumption of 20 grams of sugars each day.

Be that as it may, these types of diets aren’t valid for everyone. During the first days of application, a process known as ketogenic flu can be experienced, from which various side effects arise at the gastrointestinal level. A study published in the journal Frontiers in Nutrition confirms this. However, they usually subside over the next few days if the treatment is maintained.

Even so, the ketogenic diet doesn’t generate adherence in most people. Variety is reduced, which can lead to monotony. After all, it’s crucial to maintain a series of approaches over time in order to achieve results. If they’re not sustainable, it’s best to try another type of protocol or dietary pattern that best suits the person in question.

Exercise and ketosis to burn fat

It has been suggested that the practice of physical exercise in a situation of ketosis can be really efficient if you want to burn fat and improve your body composition. However, a series of considerations must be taken into account in this regard.

The first one has to do with intensity. Carbohydrates are the main energy substrate for strength and power activities. If their availability is low, it’s best to opt for aerobic exercise.

Also, some people who aren’t used to it might experience dizziness or a feeling of fatigue. This is derived in part from the depletion of glycogen stores, one of the main energy substrates of the body.

Once athletes adjust their ability to train in ketosis, this will decrease, but it may take some time. However, you should compete under this nutritional state.

In fact, there is some evidence that performance in the context of the ketogenic diet would be reduced regardless of the state of adaptation and the activity performed. There may be a genetic factor that modulates the adaptations, but as a general rule, the intake of carbohydrates is recommended when the aim is to achieve the maximum performance of athletes.

Even so, this approach can be useful at certain times of the season to optimize the state of body composition, especially outside of competitive periods. In these cases, it’s advisable to ensure a high protein intake to avoid the catabolism of lean mass and to achieve good tissue recovery after exertion.

Even supplementation with omega 3 could be recommended, as it has been shown to protect muscle from protein destruction.

Discover more: What Are Fatty Acids?

Is ketosis dangerous to health?

A person testing their blood sugar.
Not everyone is the same, so knowing your individual context (such as diabetes) is important when following the ketogenic diet.

For many years, it was argued that ketosis and ketogenic diets were dangerous to health. Carbohydrates are really the only non-essential macronutrients out there. This means that the body doesn’t need their dietary administration, as it can manufacture them from other elements. As we’ve mentioned, this process is carried out at the liver level and is very efficient.

At present, the use of ketogenic diets is proposed for the treatment of several types of different diseases. Not only do they serve to stimulate weight loss, but they manage to improve the treatment of diseases associated with the central nervous system. An example would be refractory epilepsy. The effect of these approaches on the risk of developing neurodegenerative diseases is even being studied.

In light of the latest studies, these approaches can be considered safe for health. It’s clear that they’re not valid for everyone, due to their problem with adherence. However, in almost no case are they harmful. They should only be avoided in athletes who perform strength sports, in pregnant women, and in children and adolescents. In all these cases, the nutritional requirements vary.

Of course, when considering a ketogenic diet to burn fat and improve body composition, special attention will have to be paid to various nutritional issues in order to meet daily requirements. For example, it’ll be crucial to achieve a balanced ratio of omega 3 and omega 6 to avoid uncontrolled inflammation situations in the internal environment. The best thing to do is to ensure regular consumption of oily fish and quality fresh food.

In the same way, it’ll be necessary to guarantee a high protein intake. There has also been much discussion about the incidence of these nutrients on health.

Recent reviews confirm that not only do they not cause damage to the liver and kidneys in the medium term, but they also protect the bone from possible fractures in the medium term. This contrasts with the hypothesis that hyperproteic diets increase urinary calcium excretion, causing bone demineralization.

Ketosis is an optimal mechanism for burning fat

Ketosis is a physiological mechanism that promotes the mobilization and oxidation of fats for energy generation. It can help you to burn fat and lose weight, although it will be important to ensure a hypocaloric environment.

If more calories are consumed than are expended each day, it won’t be possible to achieve an improvement in body composition at the level of adipose tissue reduction. On the other hand, it’s key to note that these types of ketogenic diets aren’t optimal for gaining muscle, although they are for maintaining it.

To finish, we must mention that one of the important points of nutrition is adherence. Many different dietary approaches can be carried out, but the important thing is that the patient manages to maintain them in the medium term. Otherwise, frustration and abandonment may appear, which would make them return to a place that’s even worse than where they started. The best thing will be to test tolerance and act progressively.



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