The ketogenic, or keto, diet may help with rapid weight loss and blood sugar control, but experts caution that following the restrictive eating plan long-term may not be suitable or safe for everyone.
The keto diet has become increasingly popular in recent years because of claims that it can accelerate weight loss and improve overall health. However, nutrition experts say the highly restrictive approach can be difficult to maintain and may cause health problems in some people.
Nutritionist Rachel Kleinman said the ketogenic diet was originally used primarily to help control seizures in children with epilepsy, while research into its effectiveness as a long-term treatment for obesity or diabetes remains limited.
The keto diet drastically reduces carbohydrate intake and encourages the body to use ketones, produced from fat, as its primary source of energy instead of glucose.
This metabolic state is known as ketosis. It is a natural response in which the body turns to an alternative energy source when carbohydrate availability is severely restricted, similar to what occurs during prolonged fasting.
Under a typical ketogenic diet, around 75% of daily calories may come from fat, 20% from protein and just 5% from carbohydrates. Daily carbohydrate intake is often restricted to approximately 20–50 grams.
Experts say it can take around 72 hours for the body to enter ketosis, although the timing varies from person to person.
People following a keto diet commonly eat fatty fish, eggs, meat, butter, oils, certain dairy products, nuts, seeds and low-carbohydrate vegetables.
Weight Loss May Not Last
Nutritionist Mary Condon said the keto diet can reduce body weight and blood sugar levels, but it may often provide only a temporary solution.
According to experts, many people find it difficult to maintain such strict dietary restrictions over a long period. Once they stop the diet, they may regain the weight they lost, and in some cases may gain even more.
Experts therefore recommend consulting a doctor before starting a major dietary change, particularly for people with diabetes or other underlying health conditions.
Potential drawbacks associated with the keto diet may include low blood pressure, kidney stones, constipation, nutritional deficiencies and a possible increase in cardiovascular risk, depending on the foods used to meet the diet’s high fat requirements.
What Is the ‘Keto Flu’?
Some people experience a group of symptoms commonly referred to as the “keto flu” during the first few days of starting the diet.
Keto flu is not an actual infection. Instead, it describes symptoms that can occur as the body adjusts to using ketones for energy.
Possible symptoms include digestive problems, dizziness, reduced energy and mood changes.
Experts emphasize that there is no single diet that works equally well for everyone. People considering keto or another restrictive eating plan should take their individual health circumstances into account and consult a doctor or qualified nutrition professional before making significant dietary changes.