Does Losing Weight with Ketosis Make Sense?

Ketosis is a metabolic state characterized by an increased concentration of ketone bodies in the patient’s blood. Ketosis lowers blood pH, which can lead to metabolic acidosis, potentially resulting in death. In the absence of glucose, which is the body’s primary energy source, ketone bodies can serve as fuel for extrahepatic tissue. One of the consequences of ketosis is weight loss, which is why low-carb diets have become popular among those seeking to lose weight. The ketogenic diet is also used in the treatment of epileptic seizures and certain metabolic disorders. For normal cell and body function, it is essential for extracellular fluids to maintain stable conditions. The acid-base status of the body is assessed by measuring its key regulated components: H+ concentration, partial pressure of CO2, and bicarbonate ion concentration. The acidity of solutions and body fluids is expressed by pH (pH= -log [H+]). Normal blood pH, maintained by buffers, varies within narrow limits (7.35-7.45). Blood pH can decrease (acidosis) or increase (alkalosis), which can lead to health problems. Metabolic acidosis increases proton concentration in the blood due to metabolic disturbances and can occur in individuals with untreated diabetes, starvation, or diets high in protein and low in carbohydrates. All the above metabolic conditions lead to ketosis—excessive production of ketone bodies.

Ketosis

Ketosis is a metabolic state in the human body resulting from a deficiency of carbohydrates, which in turn leads to the production of ketone molecules during fat metabolism. In this state, there is an increased concentration of these compounds in the blood and urine. The compounds appearing in ketosis are known as ketone bodies. Ketone bodies include three types of chemical compounds, as shown in Figure 1: acetoacetate and β-hydroxybutyrate, which are relatively strong acids, and acetone. They are produced as byproducts during the β-oxidation process in mitochondrial liver cells when excessive concentrations of acetyl-CoA are released due to rapid breakdown of fatty acids.
The body has mechanisms responsible for regulating acid-base balance. If metabolism or diet is disturbed, health issues can arise. Metabolic acidosis occurs in individuals with untreated diabetes, starvation, or altered diets. All the above metabolic conditions lead to ketosis and ketone body production. Ketogenesis, or the production of ketone bodies in the body, is crucial for normal functioning in small amounts, but when excessive, the concentration of these compounds increases, resulting in ketosis. Picture 1: Ketonic bodies Ketone bodies are synthesized from acetyl-CoA, primarily in the mitochondria of liver cells. The synthesis begins with two molecules of acetyl-CoA, which is otherwise a normal intermediate in fatty acid breakdown. First, acetoacetyl-CoA is formed, which then reacts with another molecule of acetyl-CoA to produce 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA). This is followed by the cleavage of HMG-CoA into acetacetate. Ketone bodies diffuse from the liver through the hepatocyte membrane into the blood, circulating throughout the body. In peripheral tissues, they diffuse through membranes into cells, where they are oxidized into acetyl-CoA, which then enters normal metabolism (acetyl-CoA enters the citric acid cycle for further oxidation).
The heart, skeletal muscles, brain, and some other tissues can use acetoacetate and D-β-hydroxybutyrate as fuel instead of glucose, as can the intestinal mucosa and adipocytes (fat cells). Ketone bodies can cross the placenta to reach the fetus but are useless to the liver and red blood cells, which cannot use ketone bodies as an energy source.

Weight Loss

As the body adapts to specific living conditions, it maintains basic functions during weight loss by using metabolic fuel stored as glycogen, fat, and eventually protein. During weight loss, energy intake is significantly less than expenditure, leading to insufficient energy supply to body cells.
In most cases, an individual has a reserve of triacylglycerols sufficient to survive for a month or more during complete starvation. A negative consequence of fatty acid breakdown is the production of increased amounts of acetyl-CoA, which in turn leads to the formation of ketone bodies.
Total liver and muscle glycogen, depending on physical activity, is sufficient for 12 to 18 hours. When glycogen and glucose concentrations decrease, the heart, liver, and skeletal muscles start using fatty acids as fuel, while the brain requires glucose or ketone bodies for functioning. After three days of starvation, one-third of the brain’s energy needs are met through the oxidation of ketone bodies.
Muscle proteins also serve as an energy source through the oxidation of amino acids, but excessive breakdown of muscle proteins results in the loss of important enzymes and muscle mass. Therefore, skeletal muscles use ketone bodies as an energy source. This adaptation occurs through various metabolic pathways: β-oxidation of fatty acids, gluconeogenesis, and ketone body metabolism.
Death after prolonged starvation generally occurs not due to starvation itself but due to the depletion of fat reserves or protein deficiency, which causes respiratory muscle failure.

Diabetes

Diabetes mellitus is a widespread metabolic disorder that occurs in patients due to a lack of insulin effect. The deficiency of this peptide hormone affects the metabolism of carbohydrates and fatty acids. When people fast or are hungry, glucose supply is insufficient for normal metabolism, making alternative energy pathways important. In diabetes, where blood glucose levels are elevated, the cause is a metabolic disorder in cells that cannot use glucose due to a lack of insulin (Type I DM) or due to a disruption in the insulin response mechanism (Type II DM). Consequently, metabolic processes adjust so that triacylglycerols can be used as fuel. The metabolic pathway of ketone bodies also becomes important here. Patients with untreated Type I diabetes consequently produce a higher concentration of ketone bodies, leading to the characteristic state of ketosis.

Ketogenic Diet

The ketogenic diet and its numerous variations have recently become increasingly popular, mainly due to their effectiveness in shedding excess weight. When we talk about a ketogenic diet, we refer to a dietary approach where carbohydrates constitute a very small proportion, and metabolic pathways in the body are redirected to utilize fats. A suitable menu for a ketogenic diet is shown in Figure 2.

MEAL	FOOD EATEN	PROTEIN (17% energy)	CARBOHYDRATES (<3% energy)	FATS (>8% energy)	CALORIES
Breakfast	2 whole baked eggs 25 g of cottage cheese	20 g	1 g	22 g	282kcal
A snack	100 g of lettuce 2 tablespoons of olive oil	1 g	1 g	30 g	278kcal
Lunch	200 g of sour cream 1 tablespoon of linseed oil	5 g	7 g	50 g	498kcal
Dinner	120 g of green salad 2 tablespoons of olive oil	1 g	1 g	32 g	296kcal
TOTAL:		27 g [108kcal]	10 g [40kcal]	134 g [1206kcal]	1354kcal

Picture 2: An example of keto diet The ketogenic diet can induce mild ketosis in individuals, similar to that seen with weight loss. People adhering to this diet can only check their state of ketosis after 10 to 12 days. The concentration of ketone bodies can be determined using urine test strips. The normal level of ketone bodies in the blood is around 20 µM, whereas in ketosis, the concentration can rise to as high as 7000 µM.

Symptoms:

• Dehydration – Caused by the body’s tendency to regulate pH and thereby increase acid excretion in urine, which also removes water from the body.
• Electrolyte Imbalance – Excessive urination with acids in the urine also leads to the loss of Na+ and K+ ions.
• Kidney Stress – Resulting from excessive urination.
• Urine Concentration Issues
• Bad Breath – An unpleasant smell of acetone.
• Uncontrolled Protein Breakdown in Muscles – Amino acids are used to produce glucose.

In such cases, there can be disturbances in consciousness, leading to coma, and if not recognized and treated, it can quickly result in death. Therefore, it is essential to consult a doctor or nutritionist before starting a ketogenic diet. During the diet, it is crucial to consume adequate protein, drink plenty of water, and ensure sufficient intake of vitamins and salts.

Treatment with a Ketogenic Diet

The ketogenic diet was first introduced in 1921 based on observations that children with epilepsy who were fed only water for 25 days experienced fewer or even no seizures. At that time, doctors hypothesized that ketones produced during fasting acted against seizures. This diet also helps children with deficiencies in the enzyme pyruvate dehydrogenase complex. In such cases, ketone bodies in the brain can be used as fuel instead of the deficient pyruvate dehydrogenase, and can also serve as a source of cytosolic acetyl-CoA for acetylcholine (a neurotransmitter) synthesis.

Research on the Ketogenic Diet

Much research has been conducted on ketosis in relation to diet. Researchers have found that the ketogenic diet is not only a potential therapy for epilepsy and pyruvate dehydrogenase deficiency but may also be considered for the treatment of other diseases such as acne, Parkinson’s disease, Alzheimer’s disease, and cancer. However, in the daily practice of doctors, the ketogenic diet has only a minor role, as opinions on its treatment effects are divided. The article is sourced from Najzdravnik.com. Najzdravnik.comhttps://najzdravnik.com/blogs/blog/ali-je-smiselno-hujsati-s-pomocjo-ketoze