Remember when as a teenager, you could eat whatever you wanted and still not gain weight? Then the years rolled by and those stubborn pounds piled on despite dieting and exercise.

Now an internationally known weight loss expert and bariatric surgeon has come up with an easy-to-follow weight loss plan that can turn back the clock in only six weeks and help you get the metabolism of a teenage, which can help you combat obesity and diabetes.

In his new book, “The Appetite Solution: Lose Weight Effortlessly and Never Be Hungry Again,” Dr. Joseph Colella details how to boost your metabolism and permanently reduce your cravings for foods that pack on the pounds.

In it, he offers scientific evidence on why we are becoming an obese nation and how we can permanently and effortlessly lose weight once and for all.

“It’s really simple,” he tells Newsmax Health. “There’s nothing magical or complicated about my lifestyle plan. We’re plagued with obesity and other chronic diseases not only because we’ve become a sedentary nation, but because we are consuming far too many simple sugars.

“They’re in just about everything we eat, from processed foods to condiments like ketchup.”

Cut the sugar: By eliminating simple sugars almost entirely from our diet, and adding clean power-packed protein, we combat hunger and support muscle repair, both of which lead to permanent weight loss success.

“Simple sugars not only add pounds but they trigger food cravings so you land up eating more of them,” explains Colella. “Simple sugars are saboteurs because they are so easy to digest. They don’t have to travel through the intestines to deliver glucose to your body. They go right into the bloodstream and for the first few moments, you feel great! You’ve received an IV shot of sugar!”

The bad news is that a few hours later, after the pancreas pumps insulin into the body to drive the sugar into your body’s cells, you “crash.”

“Of course, you then crave another sugar hit so the vicious cycle goes on,” says Colella. “Eating whole foods, especially protein and complex carbohydrates must travel through the intestines to be digested and deliver sugar to the body at a much slower rate, so your metabolism stabilizes.”

Eat regular meals: Another factor that contributes to sugar cravings and weight gain is missing meals on a regular basis.

“Nothing spins your faster into a sugar cycle than missing meals,” says Colella.

Other factors: Not getting enough sleep, stress, medications, depression, anxiety, and heartburn.

“All these factors make us want to dive into that bowl of comforting mashed potatoes and other starchy foods,” he says.

Amazingly, the current fad of drinking smoothies and fresh juices is also a potential health hazard, according to Colella.

“Fruit and veggie juices without their fibrous pulp are pure sugar,” he says. “Sure you feel great after drinking a blended beverage but that’s the same sugar high you’d get from eating a candy bar.”

Build muscle: The three-phase program of “The Appetite Solution” promises to wean you off the sweet stuff while building fat-burning muscle. There’s plenty to eat with over 2,000 calories a day consisting of 30-40 percent protein, 30-40 percent complex carbohydrates and 30-40 percent fat at every meal. As phases progress, you drop the amount of simple sugar intake to a total of 5 grams per meal and 20 grams daily.

Exercise is critical and added in the second phase.

“You only need 15 minutes daily and it can be done in the comfort of your home,” says Colella. “It’s important to work on the big muscle groups, the thighs, quadriceps, glutes and chest. For example, doing a few sets of pushups and squats will achieve this goal.”

By the sixth week, the body’s metabolism has been transformed and the weight comes off naturally, and will stay off if you read labels and avoid simple sugars.

The full version of this article appeared in Health Radar newsletter. To read more, click here.