If you want to know how to lose weight fast, here’s something you need to understand:

There are many ways to exercise and diet to lose weight fast, but most won’t give you the body you want.

This is because the majority of fast weight loss protocols are just “crash diets” that burn as much muscle as fat and leave you looking “skinny fat.”

Thus, your goal shouldn’t be to learn how to lose a lot of weight fast, but how to lose fat and not muscle as quickly as possible.

That’s how you get lean, toned, and defined, not skinny, flabby, and weak.

Of course, doing this requires a different approach toward eating and training, which is what you’ll learn in this article. You’ll learn you need to know about how to lose weight quickly, the best exercise routine and diet to lose weight fast, some of my favorite tips for fast weight loss, and more.

So, let’s get started.

How to Lose Weight Fast the Wrong Way (Don’t Do This!)

When left to their own devices, most people go about cutting weight all wrong. They . . . 

  • Eat a very low-calorie and low-protein diet
  • Do lots of cardio
  • Do high-rep, low-weight resistance training

. . . which will cause weight loss, will also likely make you “skinny fat,” like these guys:

skinny-fat-guys (1)

 

Or these ladies:

Skinny Fat Women

Now, I’m not saying that these people should be ashamed of their bodies, but most people are looking to achieve something a little different.

Something, perhaps, like these guys and gals:

Skinny Fat Before and Afters

So, what did these people do that everyone else gets wrong?

Well, for a start, they didn’t fall victim to any of these fast weight loss mistakes . . .

Fast Weight Loss Mistake #1: Eating a very low-calorie and low-protein diet.

Most every popular diet to lose weight fast provides very few calories and very little protein.

The problem with this is severe calorie and protein restriction doesn’t just result in fat loss—it also results in rapid muscle loss, too.

Eating too little protein also makes it harder to stay full after meals, which increases your chances of overeating and makes fat loss more difficult. 

(And if you’d like specific advice about what diet to follow to lose body fat quickly, take the Legion Diet Quiz.)

Fast Weight Loss Mistake #2: Not lifting weights (or doing the wrong kind of weightlifting).

Many people think weightlifting is only good for building muscle, not losing fat.

Others think weightlifting is worthwhile, but focus on high-rep, low-weight weightlifting when trying to lose weight fast.

Both of these ideas are horribly misguided. 

If you want to lose weight as quickly as possible while holding on to (or building!) muscle, you have to emphasize heavy, compound weightlifting. Research shows that this is the most effective way to maintain or gain muscle while losing fat and that it directly aids fat burning by increasing your metabolism.

Fast Weight Loss Mistake #3: Doing lots of cardio.

While doing cardio can help you burn calories and thus fat, doing too much can do more harm than good.

Research shows that doing excessive cardio not only interferes with your ability to gain strength and muscle, it accelerates muscle loss and makes it harder for you to recover from your workouts.

What’s more, research shows that excessive amounts of cardio increases hunger, which makes it easier to accidentally eat too much. Overeat often enough and you’ll not just prevent fat loss, you’ll cause fat gain.

That said, there is a correct way to use cardio to lose weight, which I’ll explain in just a moment. 

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The Best Diet to Lose Weight Fast

If you want to lose weight like clockwork while preserving (or even gaining) muscle, and without struggling with hunger, cravings, or lethargy, here’s what to do.

1. Use an aggressive (but not reckless) calorie deficit of about 25%.

Studies show that the only way to lose fat is to eat fewer calories than you burn.

The reason you’re carrying excess body fat is, over time, you consistently ate more calories than you burned. And the only way to get rid of that excess fat is to do the opposite: eat less than you burn.

When you do this, you’re in a “calorie deficit” because your energy intake is less than your body needs. It must get that additional energy from somewhere, and so it taps into its own fat stores.

The larger your calorie deficit, the faster you’ll lose weight, but if you make it too large (by eating too little), you can shoot yourself in the foot by priming yourself for muscle loss and binge eating. 

We want to avoid that, but we also want to push the needle as much as we can. This way you can lose fat as fast as possible.

This is why I recommend that you set your calorie deficit at 20 to 25% (eat 20 to 25% fewer calories than you burn every day). This is enough to lose fat lickety-split without losing muscle or wrestling with excessive hunger, lethargy, and the other hobgoblins of low-calorie dieting.

If you want to learn how many calories this is for you, check out the Legion Calorie Calculator.

(And again, if you feel confused about how many calories, how much of each macronutrient, and which foods you should eat to reach your goals, take the Legion Diet Quiz to learn exactly what diet is right for you.)

2. Eat a high-protein and high-carb diet.

When we’re talking body composition, protein is by far the most important macronutrient.

Studies show that eating adequate protein helps you . . .

The bottom line is high-protein dieting beats low-protein in every way, especially when you’re trying to lose weight fast.

Despite what you may have heard, you also want to eat a high-carb diet when losing weight. 

Studies show that a low-carb diet isn’t better for fat loss, and is generally worse for preserving muscle while dieting.

In contrast, a high-carb diet will . . . 

  • Help you gain muscle and strength faster
  • Improve your mood and reduce fatigue
  • Allow you to push harder in your workouts

Furthermore, when you’re exercising regularly, your body stores the carbohydrate you eat as glycogen in your muscles instead of converting it into body fat (which can occur when you’re sedentary and eat too many calories).

So, how much protein and carbs should you eat while cutting? Simple: 

  • 1 to 1.2 grams of protein per pound of body weight per day. (And if you’re very overweight (25%+ body fat in men and 30%+ in women), you can reduce this to 40% of your daily calories.)
  • 1 to 2 grams of carbs per pound of body weight per day.

This is enough to preserve muscle and fuel your workouts while still allowing you to lose weight fast.

If you want to know more about how much protein you should eat, check out this article, and if you want to learn more about how many carbs you should eat, check out this article. 

3. Take supplements proven to accelerate fat loss.

Unfortunately, no amount of pills and powders are going to help you lose weight fast. In fact, most fat-loss supplements are completely worthless.

But here’s the good news:

If you know how to diet to lose weight fast—following the steps in this article—certain supplements can help. (And if you’d like to know exactly what supplements to take to reach your fitness goals, take the Legion Supplement Finder Quiz.) 

Here are the best supplements to lose weight quickly:

  • 3 to 6 mg of caffeine per kilogram of body weight per day. This will raise the number of calories you burn and also increases strength, muscle endurance, and anaerobic performance. If you want a clean, delicious source of caffeine that also contains five other ingredients that will boost your workout performance, try Pulse.
  • 0.1 to 0.2 milligrams of yohimbine per kilogram of body weight before training. This increases fat loss when used in conjunction with fasted training, and is particularly helpful with losing “stubborn” fat. If you want a 100% natural source of yohimbine that also contains two other ingredients that will help you lose fat faster, preserve muscle, and maintain training intensity and mental sharpness, try Forge.
  • One serving of Phoenix per day. Phoenix is a 100% natural fat burner that speeds up your metabolism, enhances fat burning, and reduces hunger and cravings. You can also get Phoenix with caffeine or without.

How to Lose Weight Fast with Exercise

Although many people have their hearts set on losing weight fast without exercise, they’re missing out on the single best way to preserve and build muscle while quickly losing fat. Here’s how to exercise properly for rapid fat loss.

1. Do a lot of heavy, compound weightlifting.

When your goal is to hold on to (or build) as much muscle as possible while losing fat quickly, nothing beats heavy compound weightlifting.

What do I mean by “heavy, compound” lifting, though?

By “heavy,” I mean primarily working with weights in the range of 75 to 85% of your one-rep max (1RM), which includes weights that you can do ~4 to 10 reps with before failing.

And by “compound,” I mean that you should focus on exercises that train several major muscle groups at the same time, like the squat, deadlift, and bench and overhead press.

Training this way doesn’t just help you build more muscle—research shows it can also help you lose fat faster. 

You don’t have to do much to reap the benefits, either: just two or three weightlifting workouts per week is enough to see noticeable improvements, and four or five workouts per week is about the maximum you’d ever need to do. 

Read this article to find a strength training program that will work for you: 

The 12 Best Science-Based Strength Training Programs for Gaining Muscle and Strength

2. Be stingy and strategic with your cardio.

When many people want to lose weight, the first thing they do is lace up their running shoes and start pounding the pavement. While this can burn a lot of calories, it’s not the best way to use cardio to lose weight fast. 

Instead, the best way to use cardio to lose weight is to do as little as needed to reach your desired rate of weight loss and stay fit, and no more.

Here’s what typically works best: 

  1. Do mostly low- to moderate-intensity cardio like walking or rucking. This will burn plenty of calories, requires very little motivation to complete, and interferes with weightlifting less than high-intensity cardio.
  2. Do small amounts of HIIT if you enjoy it. You don’t actually need to do HIIT as it’s no more effective for weight loss than low- to moderate-intensity cardio, but it does offer some health benefits you can’t get from other kinds of cardio.
  3. Do at least two easy cardio workouts per week of 20-to-40 minutes each. This is a good starting place for maintaining your health and boosting calorie expenditure.
  4. Limit the time you spend doing cardio to no more than half the amount of time you spend weightlifting each week. If you lift weights for four hours per week, don’t do more than two hours of cardio per week.
  5. Do your cardio and weightlifting on separate days if possible, and if you have to do them on the same day, try to separate them by at least six hours and avoid doing cardio on the same days you train your lower body.

If you want to know more about how to cut weight as quickly as possible using cardio, check out this article:

The Best Way to Lose Weight Fast with Exercise

3. Stay active.

You don’t need to do formal exercise to speed up fat loss. You can significantly increase calorie burning by staying physically active whenever possible throughout the day.

Every little helps, including taking the stairs instead of the escalator, doing household chores, and parking further away from work than normal, so try and find as many ways as you can to “sneak” in activity throughout each day.

These little spurts of activity might seem trifling, but research shows they can add up to hundreds of calories per day.

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How to Lose Weight Fast for Teens and Kids

Finding weight loss tips for teens and kids can be more difficult because many think of it as inappropriate. 

“What, you want me to put my child on a diet?!” is often their knee-jerk reaction. 

I sympathize with their sentiment—in a perfect world, kids and teens wouldn’t need to lose weight—but the skyrocketing rates of childhood obesity are proof positive that we don’t live in a perfect world.   

Although many parents, doctors, and health experts dogmatically insist that “kids shouldn’t diet,” the truth is that many children and teenagers can and should use diet to reach a healthy body weight. If a youngster is obese or even very overweight, every day they stay that way is damaging their health, and they absolutely should diet to lose weight quickly, safely, and healthily. 

Luckily, this doesn’t have to involve crash dieting, fad diets, or special weight loss supplements (in fact, it shouldn’t). Instead, it involves embracing a handful of healthy eating habits and eschewing a few bad ones:

1. Eat lots of protein. High-protein foods help kids feel more satiated after meals which reduces their urge to overeat (especially on high-calorie junk between meals). Protein also supports bone and muscle growth, which is essential for young, active people. 

2. Eat lots of fruits and vegetables. Fruits and vegetables are rich in vitamins, minerals, and fiber which are crucial for maintaining good health. They’re also low in calories and fat and high in water and fiber, which means they’re great for filling kids up while keeping their appetites under control. 

3. Eat a moderate amount of whole grains. Whole grains have been shown to reduce your risk or numerous health conditions, including obesity, largely because they reduce hunger more than processed, refined grains. They’re also high in fiber and many other nutrients which support good general health and digestion.

4. Minimize junk food (but don’t eliminate it entirely). The vast majority of the foods kids eat should be minimally-processed, nutrient-dense, whole foods, but that doesn’t mean they can’t enjoy their favourite dessert or junk food from time to time. The key is to teach kids that pancakes, ice cream, chips, and so forth are indulgences, not staples.

5. Stay active. Kids don’t need to play sports to be active—dancing, hiking, and playing outdoors with friends are all perfectly legitimate ways to exercise, which will improve their health and fitness, help them better control their food intake, and burn calories and lose weight.

5 Tips for Losing Weight Fast

Here are a few more wrinkles that will make it easier to lose weight quickly. 

1. Eat a high-protein breakfast.

Studies show that eating plenty of protein at breakfast can help you to eat less throughout the rest of the day and reduce cravings for unhealthy foods. You don’t need to eat breakfast if you don’t want to, but if you do like to eat breakfast, make sure it’s high-protein.

2. Avoid liquid calories.

Alcoholic drinks, sugary sodas, and fruit juices don’t offer much in the way of nutrition and can increase your calorie intake by several hundred calories per day. Likewise, cutting these out of your diet can also decrease your calorie intake by hundreds of calories per day and cause rapid weight loss. That’s why they’re best avoided when you’re trying to lose weight quickly.

3. Eat a lot of fruits and veggies.

Including fruits and vegetables with every meal aids weight loss because they’re low in calories and fat, which means you can fill up on large portions without consuming very many calories.

4. Eat at regular meal times.

This helps you eat a consistent amount of food every day and minimizes the need for snacking, which often leads to passive overeating and weight gain. 

5. Get enough sleep.

Research shows that getting enough high-quality sleep is important for maintaining a healthy weight. What’s more, getting enough sleep also helps your body burn fat instead of muscle while dieting.

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FAQ #1: Can you lose weight fast without exercise?

Absolutely.

If you’re willing to eat very little food every day, you can create a large calorie deficit without doing any exercise. However, you’ll also lose quite a bit of muscle, and you’ll probably wind up skinny fat.

That’s why it’s better to do plenty of heavy, compound weightlifting and to try to get stronger in every workout while you’re dieting. And if you want to lose fat even faster, include a little cardio in your workout routine, too. 

Many studies show that if you want to lose fat and not muscle as quickly as possible, this is the way to go.

FAQ #2: How can I lose my belly fat fast? 

Losing belly fat is the same as losing any other kind of fat—you have to burn more calories than you consume.

That said, there are a few strategies you can employ that are particularly effective at getting rid of the stubborn fat a lot of people accumulate around their belly, hip, and thigh regions.

If you want to learn the best ways to lose stubborn belly fat fast, check out this article:

Why Belly Fat Is So Stubborn (and How to Lose It)

FAQ #3: How much weight can you lose in 30 days?

Most people think they can lose weight much faster than they really can (or should).

The reality is that a safe, healthy, and realistic goal is to lose 0.5 to 1% of your body weight per week, which is around 1 to 2 pounds of weight loss per week for most people.

If you push the envelope and try to lose weight significantly faster than this, you’ll run head first into the many problems associated with “starvation dieting” like muscle loss, fatigue, overtraining, irritation and depression, and others.

This is because your starting body weight and body fat percentage has a major impact on how quickly you can (and should) lose weight.

The long story short is the more fat you have to lose, the faster you can safely and healthily lose it.

People who are very overweight (men over 25% body fat and women over 35%) can often lose 2 or 3 pounds per week without losing muscle, but people who are lean and looking to get leaner (men around 10% and women around 20%) may only be able to lose one half to one pound of fat per week.

If you want to learn how to lose weight quickly and safely if you’re very overweight, check out this article:

How Fast Can You Lose Fat if You’re Very Overweight?

FAQ #4: Why is it so hard to lose weight fast?

There are four primary reasons why people struggle to lose weight fast:

1. Many people make little dietary mistakes that stall weight loss.

For example, let’s say you add an extra 2 tablespoons of half-and-half to your coffee (40 calories), an extra tablespoon of peanut butter to your oatmeal (100 calories), and eat an extra large banana instead of the medium one you accounted for (50 calories) at breakfast.

You’ve just accidentally eaten 200 calories more than you thought, which might be enough to severely dent, or even wipe out, your calorie deficit for the day.

If you want to learn how to count calories correctly, read this article:

How to Count Calories Correctly for Effortless Weight Loss

2. When you restrict your calories to lose fat, your body tries to decrease energy expenditure and increase intake.

This “defense mechanism” is in place to fight back against the period of mild and prolonged starvation you’re forcing your body into, and can slow down fat loss, especially as you get leaner and leaner.

Check out this article to learn more:

“Metabolic Damage” and “Starvation Mode,” Debunked by Science

3. When you stay in a calorie deficit for any length of time, your body produces a stress-hormone called cortisol, which impacts the body in a variety of ways, including an increase in fluid retention.

This can be fairly significant as well. It’s possible to lose four or five pounds of fat in a month and not see a change in scale weight or the mirror due to increased water retention.

Learn more about water retention here:

What Causes Water Retention and How to Get Rid Of It

4. When you’re new to lifting weights, it’s possible to build muscle almost as quickly as you can lose fat, resulting in no change in your scale weight.

This doesn’t last long, though—a few months at most—so if the scale doesn’t change after three or so months, this probably isn’t the issue.

If you want to learn more about building muscle and losing fat at the same time, check out this article:

The Secret to Body Recomposition: Lose Fat & Gain Muscle

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