What is Ketosis – Ketosis Explained Simply + Simple Keto Discount Promo

Siim Land

This article explains what is ketosis and how you can benefit from it – ketosis explained simply – it’s simple.

What is Ketosis


Ketosis is an altered, but still natural, metabolic state that occurs either over a prolonged period of fasting or by restricting carbohydrate intake significantly, usually up to less than 50 grams per day [1].

After an overnight fast already, our liver glycogen stores will be depleted and Captain Liver starts to produce more ketone bodies. This, in return, will increase the availability of fatty acids in the blood stream, which the body then begins to utilize for the production of energy. It can be derived from both food and the adipose tissue.

  • This process is called beta-oxidation. When fat is broken down by the liver, glycerol and fatty acid molecules are released. The fatty acid gets broken down even more through ketogenesis that produces a ketone body called acetoacetate. This is then converted further into two other type of ketone bodies. (1) Beta-hydroxybutyrate (BHB), which is the preferred fuel source for the brain and (2) acetone, that can be metabolized into glucose but is mainly excreted as waste.
  • Burning glucose is called glycolysis and it creates pyruvate. All of these actions happen inside the mitochondria and you can get 25% more energy from using beta-hydroxybutyrate as fuel.

Ketosis vs Ketoacidosis

Nutritional ketosis is not the same as ketoacidosis, which causes the pH levels in the blood to drop and become acidic. This can result in a coma and eventually death. Usually, the body manages to maintain the acidity of the blood within a normal range despite the presence of ketones. Ketoacidosis occurs mostly with type-1 diabetes and excessive alcohol consumption.

After the initial period of adaptation, the body’s biochemistry will be completely altered. Approximately 75% of the energy used by the brain will be provided by ketones and the liver will change its enzymes from dominantly digesting carbohydrates to actually preferring fat [2]. Protein catabolism decreases significantly, as fat stores are mobilized and the use of ketones increases. Muscle glycogen gets used even less and the majority of our caloric demands will be derived from the adipose tissue.

Is Ketosis Safe

One fear that ordinary physicians have about the ketogenic diet is that it can’t sustain healthy functioning of an organism. How will your body and brain survive if there are no carbohydrates?

An essential nutrient is something that’s required for normal physiological functioning and the survival of the organism[3]. It cannot be synthesized by the body and thus has to be obtained from a dietary source.

Carbohydrates are non-essential, unlike amino acids and fatty acids, which we don’t actually need to live and can function very well without.

Amino acids and fat are essential building blocks of all the cells in our body. Protein is used to create new muscle tissue, whereas the lipids balance our hormones that instigate these processes in the first place and protect cell membrane.

What Our Brain Needs for Energy

The biggest reason why we have to consume so many calories every single day is to feed our hungry brain. It comprises less than 5% of our body weight but demands about 20% of our total energy expenditure. To maintain stable blood sugar levels and a caloric balance, it needs to have access to fuel all the time.

The brain can use only about 120 grams of glucose a day [4], which means you still need at least 30 grams of glucose while running on max ketones. That doesn’t mean it ought to come from dietary carbohydrates.

During a process called gluconeogenesis (creation of new sugar), the liver converts amino acids found in food and glycerol, which is the backbone of triglycerides, into glucose. While in a deep fasted state, glycerol can contribute up to 21.6% of glucose production [5]. It’s estimated that about 200 grams of glucose can be manufactured daily by the liver and kidneys from dietary protein and fat intake [6].

Is Ketosis Good for the Brain

Once you keto-adapt, your body and brain won’t even need that much glucose, as they will happily use ketones instead. Carbohydrates are the default fuel source but not because they’re better than fatty acids by any means. The body simply prefers it because it’s easy to store and quick to absorb.

However, the brain is made up of 60% fat and runs a lot better on ketones. In fact, the high amounts of fat found in animal products and meat were probably one of the driving forces of our increased brain size. By eating solely plant foods, we wouldn’t have managed to get enough excess energy for our neural network to improve itself.

In ketosis, the brain begins to use less glucose and the small amount it needs can be derived from ketogenic foods. Muscles begin to release less glycogen as well and the entire body starts using ketones for fuel. It makes the entire organism more efficient and powerful.

Ketosis Explained Simply

This is the simple explanation for ketosis, at least for me. It delved into the science but did so in an understandable manner.

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Ketosis Explained Simply in Simple Keto Video Course Siim Land
Ketosis Explained Simply in Simple Keto Video Course Siim Land

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[1]Body composition and hormonal responses to a carbohydrate-restricted diet.

[2]A high-fat, ketogenic diet induces a unique metabolic state in mice.

[3]What is an Essential Nutrient?

[4]Endocrine Notes on Glucose Metabolism (PDF)

[5]Glycerol gluconeogenesis in fasting humans.

[6]Low-carbohydrate nutrition and metabolism