Here Is How to Lose Up to 20 Pounds in a Week (And Why You Shouldn't Do It), According to Expert

Can you lose weight fast and keep it off? Yes, says one top health and fitness expert. Jillian Michaels is a fitness expert and star of The Biggest Loser. In a recent video, she reveals that it is possible to lose weight fast. At the start of the clip, Michaels points out that “nobody ever” says, “I want to lose weight slowly.” And there’s nothing wrong with that. “There's a lot of conflicting information about whether it's safe, whether you lose weight too quickly, and whether you will have loose skin. And so here's the deal. You can lose weight quickly, and you can lose weight quickly, safely, depending on how you lose it,” she maintains.

Most People Go About Rapid Weight Loss the Wrong Way

According to Michaels, most people go about rapid weight loss the wrong way. “To lose weight, we have to create a calorie deficit. You've gotta eat less food than your body is burning in a day,” she points out, noting that a pound “is about 3,500 calories,” so if you wanted to lose two pounds a week, you would need to burn a thousand extra calories a day. “This is where diets get dangerous,” she says.

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Starving Yourself Throws Off Your Hormones

She explains that when people diet and do “things like fasts and cleanses or dramatic calorie reduction,” they are usually depriving their body of nutrients. “There's a reason people talk about yo-yo dieting,” she says, explaining that you will lose weight, but gain it all back. “When you starve the body, you're telling your body, ‘Oh my god, food is really scarce’” which then shifts your hormone balance, “to store more fat and I'm going to cannibalize my own healthy tissue because I need fat to insulate my vital organs,” she says.

It “Messes Up” Your Metabolism

“The bottom line is it messes up your metabolism, and when you start eating normally again, if you even go back to normal, because a lot of times with these dramatic diets, there's a huge pendulum swing the other way, you've now damaged your metabolism,” she says. “You're going to put the weight you lost on and then some.” This is yo-yo dieting. “Plus, when we starve ourselves, we've lost lean tissue, lean body mass, which also compromises your metabolism. So it's this really dangerous, bad cycle.”

You Also Won’t Be Able to Exercise

“Plus, how much are you really going to lose? So what are you going to run on 500 calories a day? Well, you're certainly not exercising on 500 calories a day. I mean, and even if you were, what did you burn? 2,000 calories a day?” she points out. This might help you lose three pounds a week, but you will “starve your body and do a ton of damage. Like you can't starve the weight off. It's just not possible,” she says.

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If You Want to Lose Weight Rapidly, You Need to Exercise

The answer to losing weight fast, according to Michaels? “Rapid weight loss comes from exercise,” she says. “If you're maintaining your weight, it's going to be all food. If you don't overeat, you're not going to get any bigger, okay? If you're trying to lose weight, it's like 80% exercise because you can't starve it off,” she says. “It requires more energy to move your body, period,” she adds, noting that “certain fitness techniques” are better than others for energy. They include HIIT, plyometrics, free weights, and metabolic circuits.

Women Should Never Drop Below 1,200 Calories and Men, 1,500

“If you want to lose weight quickly and safely, this is the absolute bottom line for women. Do not go below 1200 calories and you can have unlimited green vegetables. You gotta count the stuff you put on them, but you can eat unlimited greens because the reality is that you're going to get more fiber, more phytonutrients, and it almost requires as much energy for you to break down and metabolize that food than the amount of energy that's actually in the food. As a man, I never would go below, never would go below 1500 would not do it,” she says.

You Can Do 4 to 5 Hours of Higher Intensity Exercise a Week

She explains that you can do four to five hours of higher intensity training a week. “I don't mean four to five hours of the craziest techniques like HIIT and this and that. You can do like a good hour of resistance training in circuits with free weights, multiple muscle group exercises, squat thrusters, things of that nature. Pull ups, pushups that are going to burn more calories. You can work HIIT intervals into those sessions, four to five hours of intensity a week maximum.”

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And, the Rest of Your Exercise Should Be Lower Intensity

“The rest has gotta be low intensity activity,” she says. This includes hiking, walking, biking, swimming, “so that you're not over training, you're not overstressing, you're not putting your body at risk of injury, you're still giving your body enough recovery time,” Michaels continues. “I always call that kind of low intensity cardio, the bread and butter of extreme weight loss.”

If You Want to Lose Weight Fast, Do as Much Lower Intensity Cardio As You Can

“If you want to lose a lot of weight, it's a lot of that low intensity cardio, a lot of it. And that's where it's not realistic, but it is safe. It is okay,” she says. “The extremes, that's where things get dangerous.”

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And, Here Is the Truth About Loose Skin

As for loose skin, “contrary to popular belief, it doesn't matter how quickly you lose weight. If you've got loose skin, you've got loose skin and that's it,” Michaels says. “The skin is an organ. How it rebounds after weight loss has a lot of different factors and components, one of them being genetics.” And if you enjoyed this article, take advantage of these 15 Quick Ways to Lose Body Fat Percentage in a Week.