People promoting the diet say it uses the body’s own fat burning system to help people lose significant weight in as little as 10 days.
It has also been known to help moderate the symptoms of children with epilepsy, although experts are not quite sure why it works.
Proponents say the diet can produce quick weight loss and provide a person with more energy.
However, critics say the diet is an unhealthy way to lose weight and in some instances it can be downright dangerous.
What Is Ketosis?
The “keto” diet is any extremely low- or no-carbohydrate diet that forces the body into a state of ketosis.
Ketosis occurs when people eat a low- or no-carb diet and molecules called ketones build up in their bloodstream.
Ketosis is actually a mild form of ketoacidosis. Ketoacidosis mostly affects people with type 1 diabetes. In fact, it is the leading cause of death of people with diabetes who are under 24 years of age.
However, many experts say ketosis itself is not necessarily harmful.
Some studiesTrusted Source, in fact, suggest that a ketogenic diet is safe for significantly overweight or obese people.
However, other clinical reviews point out that patients on low-carbohydrate diets regain some of their lost weight within a year.
The keto diet was created by Dr. Gianfranco Cappello, an associate professor of surgery at the Sapienza University in Rome, Italy.He claims great success among thousands of users. In his studyTrusted Source, more than 19,000 dieters experienced significant, rapid weight loss, few side effects, and most kept the weight off after a year.
According to the reported results, patients lost an average of 10.2 kilograms, or about 22 pounds, after 2.5 cycles of the keto diet. Cappello concluded that the diet was a successful way for overweight and obese people to lose weight, and the few side effects, such as fatigue, are easily managed.Bette Klein, a registered dietitian at Cleveland Clinic Children’s Hospital, has used the keto diet for years to help ease the symptoms of children with epilepsy.
She told Healthline it is particularly effective with children with refractory epilepsy who have not responded well to at least two different drug treatments.
Klein said about half of these children who go on the diet see a reduction in the number of seizures they have.
The dietitian said, however, that medical professionals are not sure why the diet works in these cases.
“There is not a clear definition of what is happening,” she said.
Rudy Mawer, a sports nutritionist, has also found some success with the keto type of diet.
He said he uses this low-carb approach with some people who have trouble losing weight. He also has high performing athletes on the plan.
Mawer told Healthline there are a number of benefits to the program.
One benefit is its quick results. People can lose some initial weight rapidly and that, in turn, helps encourage them.
“You can get motivated by this weight loss,” he said.
He added the keto diet is simple in concept. It eliminates a food group, making it easier for people to follow.
He said the diet also makes people feel full despite having fewer calories and it gives them more energy. That’s because, he said, people are giving up their sluggish diet of processed foods. He added the keto diet keeps blood sugar levels stable, which produces a more stable flow of energy.
Mawer notes there are some drawbacks.
He said the diet would not necessarily improve athletic performance, a fact that may discourage some athletes.
He added people need to adhere closely to the program or it will not work.
“It is a very strict diet,” said Mawer. “You have to do everything right.”
Every individual, he notes, is different and will react differently to such a program.
“What’s great for one person can be horrible for another person,” he said
When It’s Unhealthy
Critics say the keto-type diets usually work only in the short term and can be unhealthy.
For starters, most of the lost weight is water weight, according to Lisa Cimperman, R.D.N., a clinical dietitian at University Hospitals Case Medical Center in Cleveland, Ohio, and a spokesperson for the Academy of Nutrition and Dietetics.
“Once your body enters ketosis, you also begin to lose muscle, become extremely fatigued, and eventually enter starvation mode. Then it actually becomes even harder to lose weight,” Cimperman told Healthline.
Mawer said he doesn’t believe the keto diet causes muscle loss. He did caution it’s not optimal for someone trying to gain muscle.
Other experts interviewed by Healthline had stronger words of caution.
“Keto diets should only be used under clinical supervision and only for brief periods,” Francine Blinten, R.D., a certified clinical nutritionist and public health consultant in Old Greenwich, Connecticut, told Healthline. “They have worked successfully on some cancer patients in conjunction with chemotherapy to shrink tumors and to reduce seizures among people suffering from epilepsy.”
In the general population, Blinten said a keto diet should only be considered in extreme cases.
“It can do more harm than good. It can damage the heart, which is also a muscle,” she explained.
Anyone with type 2 diabetes can benefit from weight loss and a reduced-carb diet because it will improve insulin sensitivity, Cimperman explained.
“But there are many other ways to do it besides a fad diet that won’t keep weight off long-term,” she said.
Blinten, who has used a keto diet for some cancer patients in specific circumstances, cautioned, “people will do anything to get the weight off.” However, a keto diet will do more harm than good for the majority of patients, especially if they have any underlying kidney or liver issues.
“People are using this for cosmetic reasons, but it’s so extreme that it’s dangerous,” she said.
The Feeding Tube Approach
Some have taken the keto diet a step further, using a feeding tube inserted into the esophagus through the nose.
Dieters adhere to a strict 800-calorie high-protein, no-carb diet administered through the tube by a slow-drip pump mechanism. Only black coffee, tea, or water is allowed in addition to the liquid diet.
A Florida doctor, Oliver Di Pietro, has been offering this tube diet to anyone who can pay the $1,500 cost. According to a 2012 local news report, Di Pietro learned of the diet while on a trip to Italy. He insists the keto diet is safe and effective, even for those wanting to shed just a few pounds.
“This is a ridiculous approach to weight loss,” said Cimperman.With an 800-calorie-a-day diet, “you’re essentially starving yourself,” Cimperman said. “Of course you will drop weight.”
Anything under a 1,200-calorie daily diet is considered a starvation diet and is not meant for long-term weight loss.
Tube feeding is a legitimate tool in a hospital setting, she explained.
“Someone who is on a ventilator, or can’t swallow because of a stroke or cancer, might have to eat this way. But it’s usually used as a last resort,” she said.
“In an otherwise healthy individual it can create serious complications, including infections if the tube gets contaminated, increased sodium levels, and it can cause dehydration and constipation,” Cimperman added. “What would even possess people to want to walk around with a tube up their nose?”
Melinda Hemmelgarn, a registered dietitian in Columbia, Missouri, and host of the Food Sleuth radio show, told Healthline, “It’s crazy to consider sticking a tube down your nose to lose weight. It sounds to me like somebody is making a lot of money on someone else’s vulnerabilities. Just say no to this idea.”
Don’t Become Weight Obsessed
Hemmelgarn advised anyone thinking of going on a fad diet to “keep food in perspective. It’s a gift. It’s how we nourish ourselves and stay well.”
Marketing this diet to brides just plays into our weight-obsessed society, according to Hemmelgarn.
Instead, anyone preparing for marriage should nourish herself well, engage in plenty of physical activity like walking, jogging, or bike riding, and be good to herself by eating fresh, whole, minimally processed organic foods.
There is no magic bullet for long-term weight loss, said Blinten. For long-term weight control, a Mediterranean style diet focused on fruit, vegetables, whole grains, beans, fish, and olive oil, is one that can be healthy for life.
“We fall prey to wacko diets, but the truth is there’s no quick fix,” Blinten said. “Cutting refined carbs and replacing them with fresh fruits, vegetables, and lean protein, cutting processed foods, and avoiding too many additives will keep you healthy in the long term.”
Cimperman said the healthiest approach to weight loss is to set realistic goals and ask yourself if your diet plan is:
- good for the long term
- includes exercise
- meets your long-term health goals.
If the answers are no, then that is a red flag, she cautioned.
Blinten advised dieters not to skip meals because your body goes into overdrive the next time you eat. That can actually cause you to eat more, not less. She suggested eating your largest meal at midday, then having a healthy afternoon snack.
“It keeps your metabolism and insulin levels more regular,” she explained.
Exercise, of course, is also vitally important. Every pound of muscle equals 50 calories burned, so a plan that includes a muscle enhancing regimen will help you reach your goal faster.
Hemmelgarn added, “Stay away from fashion magazines. They make us feel inadequate. If you are even considering this insane approach to weight loss, go for a walk … right now! It’ll clear your head.”