... is a normal metabolic process. When the body does not have enough glucose (derived from sugars and starches) for energy, it burns stored fats instead; this results in a build-up of acids called ketones within the body.
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Ketosis occurs when the body does not have sufficient access to its primary fuel source, glucose.
Ketosis describes a condition where fat stores are broken down to produce energy, which also produces ketones, a type of acid.
In small amounts, ketones serve to indicate that the body is breaking down fat, but high levels of ketones can poison the body, leading to a process called ketoacidosis, a serious condition that can prove fatal.
People with type 1 diabetes are more likely to develop ketoacidosis, for which emergency medical treatment is required to avoid or treat diabetic coma.
Some people follow a ketogenic (low-carb) diet to try to lose weight by forcing the body to burn fat stores.
These health benefits could be due to the loss of excess weight and eating of healthier foods, rather than a reduction in carbohydrates. Longer-term adherence to the ketogenic diet does not appear to yield great benefit.