Dietary trends typically exhibit varying degrees of staying power. So-called "fad diets" may not withstand long-term scrutiny, while approaches like the Mediterranean diet appear to be more effective and beneficial to short- and long-term health.
Low-carb diets tend to garner lots of attention. One such diet making waves of late is the keto diet. Keto diets may vary, but many are built on a foundation of low carb intake and high protein consumption. While these diets are referred to as "keto diets," the Harvard Medical School notes that a true ketogenic diet is different from the keto diets that have become so popular.
What is a ketogenic diet?
A ketogenic dietary plan focuses on fat rather than protein. A ketogenic diet is low-carb and relies on fat to supply as much as 90 percent of a person's daily calories.
How does a ketogenic diet work?
The ketogenic diet tries to force the body into using a different type of fuel known as ketone bodies, which are a type of fuel produced by the liver from fat stores. This differs from other diets, which rely on glucose from carbohydrates to fuel the body.
Getting the liver to create ketone bodies and reach a state of ketosis, in which the body is breaking down protein and fat for energy, isn't necessarily easy, as it requires people to consume fewer than 20 to 50 grams of carbs a day. To put that in perspective, the Harvard Medical School notes that a medium-sized banana typically contains 27 grams of carbohydrates. In addition, WebMD notes that reaching ketosis typically takes three to four days, and eating too much protein can interfere with the body's ability to get there.
Is a ketogenic diet safe?
The Harvard Medical School notes that a ketogenic diet is typically recommended to reduce the frequency of epileptic seizures in children. People considering a ketogenic diet to lose weight may end up disappointed and could even be putting their health in jeopardy.
"While (the ketogenic diet) also has been tried for weight loss, only short-term results have been studied, and the results have been mixed," said registered dietitian Kathy McManus, director of the Department of Nutrition at Harvard-affiliated Brigham and Women's Hospital. "We don't know if it works in the long term, nor whether it's safe."
Others may look to a ketogenic diet to combat heart disease, certain brain diseases and even acne. However, WebMD notes that there is not enough research to support the idea that a ketogenic diet can help with any of these conditions.
Ketogenic diets carry certain risks. The Harvard Medical School notes that such risks include nutrient deficiency, liver problems, kidney problems, and constipation. In addition, the sugar from carbohydrates aides brain function, so a low-carb diet like the ketogenic diet can have an adverse effect on the brain, potentially contributing to confusion and mood swings.
People considering ketogenic diets or other popular low-carb approaches to nutrition should consult with their physicians before making any changes to their existing diets.