WASHINGTON — The ketogenic or “keto” diet is defined by healthline.com as a very low-carb, high-fat diet that shares many similarities with the Atkins and other popular low-carb diets.

By drastically reducing carbohydrate intake and replacing it with fat, the diet puts the body into a metabolic state called ketosis. Once this happens, the body burns fat for energy.

As a new year brings in new resolutions for health and fitness, some may be considering the popular keto lifestyle. Anthony Gustin, founder and CEO of Perfect Keto, told CNN in September that “growth has been pretty wild,” adding that his company averaged 20 percent growth each month in the last year.

But here’s the million dollar question: Is the keto diet safe?

Best-selling author and former host of “The Biggest Loser” Jillian Michaels says no.

“Here’s the thing they’re not telling you about keto,” said Michaels. “It has a ton of oxidative stress on the body.

“There’s zero calorie restriction, tons of animal fats, tons of saturated fats. We’re seeing study after study that diets like this are shaving years off our lives [up to seven years].”

The keto lifestyle, she said, shortens telomeres and starves micromolecules. “The No. 1 insulin sensitizer doesn’t require a medical state of emergency for your body like keto,” Michaels said. ” … It’s actually exercise.”

Michaels’ latest book is “The 6 Keys: Unlock Your Genetic Potential for Ageless Strength, Health and Beauty.”

Those looking to change their eating habits to shed some pounds, may benefit from taking Michaels’ recommendation: implement the Mediterranean diet to get the benefits of the keto diet without the negative side effects.

“Not eating too much, eating on a particular schedule, creating an overnight fasting period, and doing your best to work in foods that are very rich in micronutrients, antioxidants, vitamins, minerals, probiotics, prebiotics and so on is going to be the best program period — end of story,” she said.

“It’s not my take on it. It is science, just like two plus two equals four.”

Hear the full interview below — including how much daily sleep you need to be your best.