The popular low-carb diets (such as Atkins or Paleo) modify a true keto diet. But they come with the same risks if you overdo it on fats and proteins and lay off the carbs. So why do people follow the diets? "They're everywhere, and people hear anecdotally that they work," McManus says. Theories about short-term low-carb diet success include lower appetite because fat burns slower than carbs. "But again, we don't know about the long term," she says. "And eating a restrictive diet, no matter what the plan, is difficult to sustain. Once you resume a normal diet, the weight will likely return."
Another analysis of popular diets published in the Annals of Internal Medicine in April 2015 found the Atkins diet to result in more weight loss than simply educating people on portion control, but also noted that most of the studies of this low-carb diet involved registered dieticians helping participants make food choices, rather than the self-directed process by which most people pick up the diets. That's true of many diet studies, the researchers noted, so study results likely look rosier than weight loss in the real world.
Fairly recently, the diet was introduced as a weight-loss diet by an Italian professor of surgery, Dr. Gianfranco Cappello of Sapienza University in Rome. In his 2012 study, about 19,000 dieters received a high-fat liquid diet via a feeding tube inserted down the nose. The study showed an average weight loss of more than 20 pounds in participants, most of whom kept it off for at least a year. The researchers reported a few minor side effects, like fatigue.
The ketogenic diet is not a benign, holistic, or natural treatment for epilepsy; as with any serious medical therapy, complications may result.[28] These are generally less severe and less frequent than with anticonvulsant medication or surgery.[28] Common but easily treatable short-term side effects include constipation, low-grade acidosis, and hypoglycaemia if an initial fast is undertaken. Raised levels of lipids in the blood affect up to 60% of children[38] and cholesterol levels may increase by around 30%.[28] This can be treated by changes to the fat content of the diet, such as from saturated fats towards polyunsaturated fats, and if persistent, by lowering the ketogenic ratio.[38] Supplements are necessary to counter the dietary deficiency of many micronutrients.[18]
The ketone bodies are possibly anticonvulsant; in animal models, acetoacetate and acetone protect against seizures. The ketogenic diet results in adaptive changes to brain energy metabolism that increase the energy reserves; ketone bodies are a more efficient fuel than glucose, and the number of mitochondria is increased. This may help the neurons to remain stable in the face of increased energy demand during a seizure, and may confer a neuroprotective effect.[56]
Burns fat: You can drop a lot of weight — and quickly — on the keto diet.[3] Ketones suppress ghrelin — your hunger hormone — and increase cholecystokinin (CCK), which makes you feel full.[4] Reduced appetite means it’s easier to go for longer periods without eating, which encourages your body to dip into its fat stores for energy. Learn more here about the keto diet and weight loss.
Anticonvulsants suppress epileptic seizures, but they neither cure nor prevent the development of seizure susceptibility. The development of epilepsy (epileptogenesis) is a process that is poorly understood. A few anticonvulsants (valproate, levetiracetam and benzodiazepines) have shown antiepileptogenic properties in animal models of epileptogenesis. However, no anticonvulsant has ever achieved this in a clinical trial in humans. The ketogenic diet has been found to have antiepileptogenic properties in rats.[56]
People claiming huge benefits of these supplements – despite the lack of solid scientific support – may sometimes have a financial reason to believe in the supplements. Some of these products are sold under a multi-level marketing arrangement, where sales people are paid based on commission. For example, the company Prüvit sells drinkable ketones, called KETO//OS with a multi-level marketing structure.
