The hottest new diet is the Keto diet, with celebrities from Halle Berry to Kourtney Kardashian. The Keto diet promises to help people lose weight, but what are the pros and cons of this regimen?

What is the Keto diet?

The Keto diet is a high-fat, low-carb diet. The diet is supposed to change the source of a person's energy from glucose formed by carbs to ketones made from fat.

What can you eat on the Keto diet?

Fats are a key food, but healthy fats only. Avocados are a go-to superfood, along with egg yolks and olives. Fruits and veggies are also a must-have. The only limited food would be carbs, so cut back on or just cut out bread or pasta. In addition to specific foods, there is a period where you don't eat at all. There is a recommended period of intermittent fasting for a few hours to let the body recover and rest.

What are the benefits of the Keto Diet?

There can be many benefits to the diet, according to Pegah Jalali,clinical coordinator at the New York University Comprehensive Epilepsy Center. The diet is sometimes used to help children with epilepsy control seizures. The high-fat diet makes people feel fuller for longer. "Fat has a longer intestinal transit time compared with carbs,” she says. “So it will prolong that feeling of fullness, especially in between meals,” said Jalali.

Social media star Kristie Sullivan also swears by the diet. "I did it for two weeks and the first three days I noticed the hunger wasn't there. The hunger my entire life wasn't there," Sullivan said. "I didn't even eat lunch. That was the first sign my body was responding, I lost weight and by the end of the second week I knew this was going to be the way I ate," said Sullivan to the ABC News affiliate in Houston. A Shape magazine writer also tried the diet and said she lost weight and gained energy.

What are the downsides of the Keto diet?

As with any diet, there are drawbacks. The simplest could be just missing carbs.
"It might be easy in the short-term to go for carb-free foods but at a certain point, the thought of not being able to eat your favorite foods again can become daunting," said Alix Turoff, a registered dietitian. said Alix Turoff, a registered dietitian

There are also more serious physical side effects when people start the Keto diet. Cutting carbs can be dangerous. "These include fatigue, dizziness, lightheadedness, poor sleep, difficulty with exercise, and constipation, all resulting from extreme restriction of carbohydrates," said Jennnifer Brown, a faculty associate at Arizona State University's School of Nutrition and Health Promotion.

Even the doctor who has a Keto diet plan says the diet isn't a long-term solution. Dr. Axe advocates being on the Keto diet for only 30 to 90 days for maximum benefits.

No matter how long people are on the Keto diet, consult a doctor first before starting the plan. Also, make sure that the diet makes you the healthiest you can be.