Models, athletes and celebrities swear by the ketogenic “keto” diet to help shed those unwanted pounds.
The keto diet encourages eating more cheese, butter and bacon; it’s a low-carb, high-fat diet akin to the Atkins Diet created in 1972 by cardiologist Robert C. Atkins.
The latest fad diet has amassed a following of devoted supporters, including Tim Tebow, LeBron James and Kim Kardashian, but does it really work?
Carol Johnston, professor at Arizona State University, explains why the low-carb, high-fat diet is so popular, how it works, and what dieters should be eating to lose weight.
Question: Does the science behind the keto diet make sense? Would nearly eliminating carbs while increasing fat consumption help a person to lose weight?
Answer: The short answer is yes. There is mounting evidence that suggests calorie restricted, low-carbohydrate, high-protein diets are effective for weight loss, and the keto diet is an extreme version of this.
Low-carb diets can be more satiating, allowing dieters to feel full longer, eat less, and thus experience greater weight loss success. However, calorie restricted, high-carb diets are also effective for weight loss.
Overwhelmingly, the most important factor in weight loss success is diet adherence. In research trials, most individuals who lose weight regain most of it within a year, regardless of which diet they were on.
The downside of many of the fad diets you see today is the lack of emphasis on long-term lifestyle changes, which is necessary for long-term weight loss success.
Q: In your opinion, why is this diet so popular?
A: The keto diet is popular because it is easy to follow and on the surface seems effective. In the first few days after starting the keto diet, a person can experience a significant loss of water weight.
When carb intake is restricted for a few days, glycogen stores in the muscle are reduced. Glycogen is responsible for water retention, so when its levels fall, so do our water levels.
To the average person, the diet appears to be working. The number on the scale is going down. But, since most of this weight lost is water weight, it will return when the person consumes carbs again.
While most people rely on scales to monitor weight loss and think any weight loss is good, the goal is actually to lose fat, which isn’t always reflected on the scale.
Additionally, the elevated levels of satiety—feeling full—may help people stick to the diet longer and experience greater weight loss success.
Q: Is the keto diet healthy?
A: Keto diets have safely been used as an effective therapy for epilepsy for years.
There are some risks associated with an extremely low-carb, high-fat diet, including elevated blood triglycerides (linked to elevated cardiovascular risk), increased urinary uric acid (which may lead to the formation of kidney stones), and lethargy.
Adults on a low-carb diet are also at risk for adverse impacts to their bone health.