Speed keto’ combines intermittent fasting and the keto diet. It boosts weight loss, but experts say it’s a bad idea.
As the high-fat, low-carb keto diet continues to be a popular nutrition topic, variations of keto from Mediterranean keto to vegetarian, are also trending, along with a dubious market of keto products and services that promise quicker, easier results from the diet.
Enter speed keto, a combination of keto and intermittent fasting. Although there’s evidence to support both techniques, experts don’t recommend combining them, especially if you’re a beginner, since the sudden extreme shift will likely be unpleasant, and the short-term payoff isn’t worth the side effects.
Dr. Mark Cucuzzella, a professor at the West Virginia University School of Medicine who has published several studies on keto and diabetes, said that fasting can be a challenge early in the keto process since dieters haven’t yet allowed their bodies to adapt to burning fat, leading to hunger, fatigue. That added stress is not only unhealthy, but can actually disrupt the metabolism, he added.
“If you force it, if you do fasting wrong, it can break you,” Cucuzzella told Insider. “The stress response can break your endocrine system.”
Speed keto was created in 2018 by a ‘doctor’ with a PhD in education, not a medicine
Although searches for “speed keto diet plan” spiked dramatically in late February this year, according to Google Trends, it isn’t new.
“Speed keto” is a trademarked diet plan created by Harlan Kilstein, an entrepreneur and self-proclaimed “lifestyle coach.” Kilstein identifies himself as a doctor and technically, he is, with a doctorate in education, not nutrition or any other field of medicine.
Kilstein apparently became personally interested in keto for his own weight loss, according to his website, and published a cookbook titled “Completely Keto” in 2018. His Speed Keto program appears to have been launched shortly thereafter. It offers ready-made ketogenic meal plan and fasting schedule to speed weight loss or push past the well-known “keto plateau,” the phenomenon where some keto dieters find they stop losing weight within weeks or months on the diet.
The whole Speed Keto package sells online for $39, but the website claims it “has a total value of $540.”
Separately, both the keto diet and intermittent fasting can aid weight loss, if done correctly
Keto, often called a lifestyle instead of a diet, has been touted for weight loss, more energy, and better metabolic health. Recently, doctors have begun using keto as a treatment for diabetes, although nutritionists are often skeptical of the high fat in a keto diet, particularly saturated fat.
There’s also a growing body of evidence to support the benefits of intermittent fasting, including weight loss, but also prevention of chronic disease and other ailments.
However, neither is right for everyone — people with a history of disordered eating, for instance, shouldn’t attempt restrictive diets that cut out food groups (keto severely limits carbohydrates) or require not eating for long periods of time (like certain types of fasting). And it’s always best to work with a medical professional and/or nutrition expert if you’re trying to lose weight or dramatically change your diet.
But the combination of the two into “speed keto,” with the goal of participants eating just one low-carb, high-fat meal per day, has an even greater risk of becoming a crash diet, since the abrupt, dramatic change to eating habits will likely leave people hungry, fatigued, and unlikely to stick to the eating plan, according to experts.
Speed keto is especially challenging for beginners, though people do tend to eat less after a while on the keto diet
Once adapted to a keto diet, some people will naturally eat less often throughout the day, since high-fat meals are more filling, according to Dr. John Limansky, who follows a keto eating style and advocates it for his patients.
“[Speed keto] is a catchy marketing way of describing what people already do,” he told Insider.
But the key is that those people have already adapted to the ketogenic diet over time, a lengthy process that varies depending on the person, but can take two to four weeks after restricting carbohydrates, Limansky said. It’s true that fasting can speed up the process by more rapidly reducing the body’s stored energy, but it’s likely to be unpleasant, he added.
Trying to fast before then, particularly a rigorous fasting style of just one meal a day, can be challenging because the brain is used to relying on glucose for energy — without a steady supply from food, Limansky said, people can feel groggy, fatigued, and prone to cravings and hunger pangs.
“I think it’s a lot more difficult to start off that way. I recommend getting fat adapted first so you don’t experience symptoms,” he said. “Short-term, it’s more successful, but long term, it’s not sustainable.”