Dr. Mehmet Oz's weight-loss breakthrough starts with a carefully designed meal plan that maximizes fat burning with the right foods. The key is to fill up on "inefficient calories," he says. "This means that your body doesn't burn them up quickly, as it does with highly processed foods and simple carbs." What's on the menu? Protein, healthy fats, and fiber — balanced to keep you satisfied and slimming down. But there's more to this breakthrough.

It's also designed for ease and automation, and that boils down to two words: meal prep! You'll spend a few hours in the kitchen each Sunday preparing most of the components you'll need for seven days' worth of meals. (Don't worry about soggy Saturdays — the recipes in our plan had to pass this test: If a dish didn't taste as good on day seven as it did on day one, you won't find it here.)

When it's time for a meal, you simply open your fridge and grab a ready-to-eat container or reach for your premade ingredients to whip together healthy, DIY "fast food." You won't have to wonder, Do I have time to cook? Just reheat, eat, and say hi to a slimmer you in the mirror every morning.

By the end of 21 days, your body will feel rebalanced, because this diet is based on clean foods and mainly plant-based protein (including beans, power grains like quinoa, and nuts and seeds). Twice a week, you'll have animal protein, but the rest of the time, "you can think of this as a vacation from meat," says Dr. Oz. When you switch from a diet packed with processed, high-fat animal sources of protein to a plant-focused diet, you slash calories naturally. And you improve your health while you're watching the scale tick down. "Research shows that crowding out the meat on your plate with plant protein can lower your risk for cancer, diabetes, and heart disease," adds Dr. Oz. What could be more important than that?

Here's How It Works

1. Stock up groceries.

GET THE SHOPPING LIST

2. Start prepping: Set aside a few hours to cook on Sunday, or whatever day you have a chunk of time.

GET THE PREP PLAN

3. Get cozy in your kitchen: You'll chop, cook, and tuck your meals or components into containers. Stash them in the fridge, and you're set with ready-to-go, perfectly portioned breakfasts, lunches, and dinners all week.

GET THE MEAL RECIPES

How Much Weight Will You Lose?

It depends on your starting point. If you have a lot to take off, you may see 10 pounds fall away in the first 21 days. Some women who tried the plan shed 10 pounds in the first week alone. Heavier people typically drop more weight in the beginning of a diet simply because they experience a larger calorie deficit. (For example, if you were eating 3,500 calories and dip down to 1,300, that's a much bigger change than a 2,000-calorie eater would go through.) Already close to a healthy size? Even if it takes an extra week or two to reach your goal, you can get there.

This story originally appeared in the January/February 2017 issue of Dr. Oz The Good Life.