You may be hearing a lot about the ketogenic diet as a way to slim down while noshing on butter and heavy cream. This way of eating is suddenly hot among venture capitalists in Silicon Valley, who believe it will help them live longer and healthier, CNBC reports.
Some praise the high-fat/ultra low-carb plan for helping them to lose weight and have energy all day long. Other advocates say it finally helped them to get control of their body.
How does it work and could it help you?
We asked Bonnie Taub-Dix, a registered dietitian nutritionist and author of “Read It Before You Eat It”; and Keri Glassman, nutritionist, registered dietitian and TODAY Tastemaker.
To start with, both said they would never advise the ketogenic diet for weight loss.
“Cutting out carbs is usually an invitation to overeat them at another point,” Taub-Dix said. “For a diet where you’re looking to lose weight, look good and feel good… I would not recommend a diet like this.”
“For safe and effective weight loss, the carb reduction is too extreme,” Glassman added.
RELATED: Read inspiring stories of ordinary people slimming down in TODAY's My Weight-Loss Journey
Here’s what you need to know:
What is the ketogenic diet?
It’s a diet fine-tuned in the 1920s to help treat epilepsy. It does help to control seizures in some children, but it’s not recommended for adults “mostly because the restricted food choices make it hard to follow,” the Epilepsy Foundation says.
The diet has just recently begun to be touted as a weight loss plan, Glassman noted. She described it as eating “mostly fat with a teeny bit of protein and carbs.”
How does it work?
Your body normally relies on carbohydrates for energy. It breaks them down into glucose, which is your main source of fuel.
If that’s not available when you stop eating carbs, your body turns to fat for energy in a process called ketosis. Fat becomes your fuel.
RELATED: Why fat in your diet is good for weight loss
What can you eat?
In a word: fat. Lots and lots of fat.
The desired ratio in the ketogenic diet is consuming 3 or 4 grams of fat for every 1 gram of carbohydrate and protein, which amounts to getting about 75-80 percent of your daily calories from fat.
You can eat foods like butter, heavy whipping cream, mayonnaise, and oils, the Epilepsy Foundation notes.
“It’s putting butter on your butter,” Taub-Dix said. A sample daily menu might include eggs with olive oil and avocado on the side for breakfast; leafy greens, salmon, nuts and olive oil for lunch; and steak, greens, vegetables and oil for dinner, Glassman added.
It’s all about that fat to carbs/protein ratio, so even though you’re not really counting calories, the meals have to be planned very carefully to adhere to the strict formula.
What must you avoid?
Carbs. That means all breads, pastas, grains, sweets and more. You have to be extremely careful because even toothpaste may contain sugar, the Epilepsy Foundation warns.
The ketogenic diet restricts the intake of carbs to as low as 2-4 percent of calories. As a point of reference, a standard diet provides about 45-55 percent of calories from carbs, Glassman said.
RELATED: How much salt, fat and carbs a day are OK?
Would someone lose weight?
Yes, you can lose weight on the ketogenic diet. One reason is that the body burns fat for fuel. Another is that you can’t eat many of your favorite foods, like crusty bread, potato chips or sugar-laden pastries. Plus, all that fat keeps you full, so you may just skip your usual 3 p.m. snack because you’re not hungry.
But the nutritionists were adamant that if you want to slim down, this is not the way to go.
“Generally, whenever you do something like this, it’s extreme. Most extreme things, you lose weight, but that doesn’t mean it’s good… that doesn’t mean it’s healthy,” Glassman cautioned.
“It’s not really sustainable, nor is it good for you,” Taub-Dix added. “In most cases, you’re just dying to have a cracker so the weight gain is usually pretty quick as well.”
RELATED: 13 foods a nutritionist always keeps in her fridge
What about the effect on the body?
Since this diet doesn’t provide all the essential nutrients, you’d need to take supplements and multi-vitamins, Taub-Dix said. You’d also need to make sure your digestive system works properly because the diet is very low in fiber.
Bottom line
The ketogenic diet is a very restrictive plan that most people can’t stick with and shouldn’t try for weight loss, the nutritionists said. People with heart disease or diabetes should especially stay away, Taub-Dix warned.
There is one healthy takeaway, though: In general, reducing carbs and incorporating more healthy fats, like nuts and avocados and certain oils, in your diet — without going to extremes — is a good idea for most of us, both Glassman and Taub-Dix said.
“I’m a big believer in having a lot of healthy fat in your diet, and many people skimp too much on healthy fats,” Glassman said.
“If you’re eating a more well-balanced diet — eating carbohydrates that are high in fiber, whole grains, and combining it with fats, you feel good, too,” Taub-Dix noted.
Follow A. Pawlowski on Facebook, Instagram and Twitter.
This story was originally published in December 2016.