Ketosis is a natural process the body uses to make energy from fat when there is not enough glucose available. It can happen during periods of fasting or from following a restrictive, low carb diet.
When glucose (the body’s main fuel source) is low, the body starts producing ketone bodies for energy. These ketone bodies are made from the breakdown of stored fat.
Ketone bodies travel to the brain and muscles, supplying them with energy to help the body keep functioning. Symptoms may differ between individuals, but a distinct acetone-like odor on the breath is a common sign.
Ketosis symptoms
The main symptoms of ketosis are:
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Breath with a metallic taste or bad breath (halitosis);
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Increased urge to urinate;
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Increased thirst;
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Decreased appetite;
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Headache;
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Nausea and vomiting;
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Weakness;
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Upset stomach;
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Insomnia.
In general, symptoms improve after a few days or weeks. Adequate fluid and electrolyte intake is important to help prevent symptoms related to dehydration.
Ketosis vs ketoacidosis
Both conditions involve ketone bodies in the blood, but ketoacidosis results from abnormally high ketone levels caused by a disease, while ketosis is a normal metabolic process.
Ketoacidosis is usually related to type 1 diabetes. When glucose cannot get into cells, the body produces ketone bodies in an attempt to generate energy. Excess ketone production can lower blood pH (acidosis), which can lead to coma and even death if not resolved.
Confirming a diagnosis
Ketosis is primarily confirmed by measuring ketone levels in the blood or urine. A standard urine test can detect ketones through a color change on the test strip.
Although urine testing is faster, urine ketone levels can vary with hydration status. This can cause false-positive results when a person is dehydrated or false-negative results when a person drinks a lot of water.
The most reliable way to confirm ketosis is through a blood test. A small blood sample is collected and analyzed in a lab to measure the concentration of ketone bodies. Ketosis is generally defined as a blood ketone level greater than 0.5 mmol/L.
Health benefits
The main effect of ketosis is that the body starts using stored fat as an energy source, which may help with weight loss.
Ketosis can also provide enough energy for the brain to support essential body functions during periods when glucose stores are low.
Health risks
Although ketosis is a normal body process, very high concentrations can make the blood too acidic and may lead to coma.
For this reason, fasting and restrictive diets are recommended only under medical supervision or with guidance from a registered dietitian.
Ketogenic diet
The ketogenic ("keto") diet encourages the body to use fat as its primary energy source, drawing on both dietary fat and stored body fat. To achieve this, the diet is high in fat and protein but very low in carbohydrates, prompting the body to break down fat and produce ketone bodies that supply energy to the brain and muscles.
In this diet, carbohydrates usually provide about 10% to 15% of total daily calories, while fat intake is increased. A registered dietitian may suggest including foods like nuts, seeds, avocados, and fish, and limiting foods such as fruits and grains.
Because the ketogenic diet is highly restrictive, the body needs time to adapt. During this adjustment period, side effects such as diarrhea, constipation, nausea, or vomiting may occur. It is therefore important to follow the diet under the supervision of a dietitian, who can monitor ketone levels in the urine and blood and make any necessary adjustments.
Also recommended: Keto Diet Plan for Beginners: 7-Day Menu, Carb Limits & Safety Tips tuasaude.com/en/keto-diet-plan