Can the ‘Fast 800 Diet’ help you lose weight fast?

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With holiday and New Year's Eve parties over, health is on many people's mind, and many are hoping to lose a few pounds in the new year.

Often, many expect to see quick results from their resolutions, but that isn't the case for most diets.

Except for one diet, dubbed the "Fast 800" diet by New York Times bestselling author Dr. Michael Mosley. The idea consists of losing an average of 22 pounds every eight weeks.

And while the Centers for Disease Control and Prevention says slow-and-steady weight loss is best, Mosley says his plan is to lose weight quickly by eating only 800 calories a day for two to 12 weeks.

"The idea is you extend your overnight fast," Mosley told "Good Morning America." "If you combine that with 800 calories, the studies show it is even more effective."

In his new book, "The Fast 800 Diet," Mosley walks readers through what the diet entails: a Mediterranean-style diet low in sugar, carbs and calories but high in proteins like fish, chicken and eggs, plus plenty of leafy greens, combined with the overnight fast.

Some recipes that are just 800 calories and which can help shred the weight include combinations of salmon, spinach and chives. Mosley also recommends planning meals in advance and taking nuts and fruit with you for times when you'll be tempted to snack.

While the diet will help you lose the weight, Mosley said it's not about how you look, but it's about how your body will overall feel to improve your health.

"It's enough to keep you satisfied to give you all the essential nutrients you need," Mosley said, "but it is quite low so you will lose the weight rapidly and that is incredibly motivating people who do it."

“For a healthy individual, 800 calories a day for a limited period of time should be fine,” said Dr. Jennifer Ashton, ABC News chief medical correspondent. “Children, teens, people with diabetes who are insulin dependent, pregnant women or anyone with a history of an eating disorder should not try intermittent fasting.”

Additionally, Dr. Blair Chance of the ABC News Medical Unit notes that “pregnant women require approximately 300 extra calories a day” and the safety and benefits of intermittent fasting with diabetes are very limited, “especially in those with uncontrolled diabetes.”