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Key Takeaways

  1. The Legion Weight Loss Calculator is the only weight loss calculator that helps you plan how long you should cut to maximize fat loss and minimize muscle loss and tells you what and how much you should eat to reach your goal.
  2. The calculator will tell you exactly how much you should eat every day to lose weight by your goal date, as well as how you set your “macros” (protein, carbs, and fat).
  3. To use the Legion Weight Loss Calculator, enter your body weight, body fat percentage, activity level, goal weight, and the date you’d like to reach it by.

Just here for the weight loss calculator? Here you go:

Step 1: Your Current Stats
LBM
Fat Mass
BMR
TDEE
Step 2: Your Goals
I want to weigh pounds.
Your body fat percentage will be 0%.
I want to reach my goal in days.
I want to reach my goal by
Step 3: Your Calories & Macros
You will need to eat 0 calories per day to reach your goal on time.
You will need to maintain a 0% calorie deficit to reach your goal on time.
0 kcal
0 kcal
0 kcal

Want to learn how to use this weight loss calculator to lose weight faster and more efficiently? Read on.

One of the most frustrating aspects of weight loss is its unpredictability.

That is, you could be doing everything “right” on paper, only to see the scale and mirror thumb their nose at you every day.

Anybody who has tried to predict how long it’ll take to lose a certain amount of weight or reach a certain body fat percentage knows what I’m talking about.

After enough disappointments, many times, people just resign themselves to the disheartening reality that it’ll “take as long as it takes.”

What if weight loss didn’t have to be a guessing game, though? 

What if you could predict roughly how long you’ll have to restrict your calories to reach your desired body weight?

Not to the day, per se, but certainly to the week or two.

Well, while predicting weight loss will always be a bit slippery, with the right tools and know-how, you can come up with fairly accurate forecasts.

All you need is a weight loss calculator, a properly designed meal plan, a solid workout routine, and a bit of piss and vinegar, and you’ll not only reach your goal weight, but you’ll reach it as quickly and efficiently as possible.

Enter the Legion Weight Loss Calculator.

All you have to do is enter your current weight, body fat percentage, activity level, and goals, and it’ll tell you how many calories you should eat per day and how you should divide those calories into protein, carbs, and fat. 

What’s more, the calculator also tells you whether you should raise or lower your calorie intake to optimize your results. 

It also has a few bonus features for making your cuts as productive as possible, which you’ll learn about in a moment.

Before we get to how our weight loss calculator works, however, let’s back up and discuss the topic a bit more generally.

How Do Weight Loss Calculators Work?

weight-loss-goal-calculator

A weight loss calculator works by using your calorie intake, activity levels, and body fat percentage to predict how long it’ll take you to reach your desired body weight. 

Some weight loss calculators use highly complex algorithms that also take into account the natural reduction in calorie burning that occurs while dieting. 

Others simply tell you how many pounds you can expect to lose per week based on your estimated energy expenditure and intake. 

The problem with the more intricate calculators is many of the formulas they use to adjust for reductions in calorie expenditure are just rough estimates, and in the end, these calculators often produce numbers more or less the same as simpler ones.

On the other hand, oversimplified calculators that only consider your calorie intake and expenditure aren’t all that helpful, either. 

In most cases they don’t tell you how long it will take to lose weight if you follow the dietary recommendations produced by the calculator. The few that do help you estimate how long your diet will take usually don’t offer any advice on how you should adjust your diet to optimize your results. 

That’s why I created the Legion Weight Loss Calculator, which is unique for several reasons:

1. It allows you to pick a goal weight and date for reaching it, and then tells you how many calories you’ll need to eat per day to get there. 

This is perfect if you’re preparing for a specific event like a wedding, vacation, and so forth. 

2. Alternatively, it allows you to pick duration for your weight loss diet (such as 60 days), and then see what weight you’ll be able to reach within that time frame.

This is perfect if you’re the kind of person who likes to have realistic expectations and a clear light at the end of the tunnel before beginning.

3. It also allows you to pick a calorie deficit you’re comfortable with, and then see how long it’ll take to reach your goal weight if you eat that much food every day. 

This is perfect if you’re the kind of person who likes to settle into a routine while dieting, and once you’ve hit your stride, don’t much mind how long the process takes.

4. Finally, it gives you evidence-based guidelines on how to adjust your calorie intake to maximize fat loss and minimize muscle loss.

This is extremely helpful for planning how long you should give yourself to cut if you’re also trying to retain lean mass (and you should be!).

So, as you can see, regardless of your weight loss goals, this calculator has something to offer.

Whether you’re already lean and looking to get even leaner without losing strength or muscle, or if you’re very overweight and looking to lose weight as fast as possible, the Legion Weight Loss Calculator will help you reach your goal faster and more enjoyably.

So, let’s look at this calculator, shall we?

Use this workout and flexible dieting program to lose up to 10 pounds of fat and build muscle in just 30 days…without starving yourself or living in the gym.

How to Use the Legion Weight Loss Calculator

Step 1: Your Current Stats
LBM
Fat Mass
BMR
TDEE
Step 2: Your Goals
I want to weigh pounds.
Your body fat percentage will be 0%.
I want to reach my goal in days.
I want to reach my goal by
Step 3: Your Calories & Macros
You will need to eat 0 calories per day to reach your goal on time.
You will need to maintain a 0% calorie deficit to reach your goal on time.
0 kcal
0 kcal
0 kcal

The first step of using the Legion Weight Loss Calculator is to enter your current stats.

Select which unit you’d like to use–imperial (pounds) or metric (kilograms)–followed by your weight, estimated body fat percentage, and activity level, like this: 

weight loss calculator kg

If you aren’t sure what your body fat percentage is, use the images in this article to estimate your level of body fatness (and round up when unsure):

How to Calculate Your Body Fat Percentage Easily & Accurately (With a Calculator)

You have a few options to choose from in the Activity Level dropdown, from Sedentary (little to no exercise) to Extra Active (10+ hours of exercise or sports per week). 

Select whichever Activity Level best matches your level of average weekly physical activity.

For example, if you normally lift weights five times per week and each workout lasts about an hour, and you do an hour of cardio on the weekend, that’s 6 hours of exercise per week. In this case, you’d select the “Moderately Active” option (4 to 6 hours of exercise or sports per week).

And remember, this is how much you actually are consistently exercising every week—not how much you’d like to exercise or have done in the past. 

If you have a very active job like construction, military service, or so forth, choose the next highest Activity Level. 

Based on this data, the calculator computes your lean body mass, fat mass, basal metabolic rate (BMR), and total daily energy expenditure (TDEE).

Your BMR is the number of calories your body burns every day just to keep you alive, and your BMR plus however many calories you burn through activity and digesting food gives you your TDEE. 

If the preset activity levels don’t accurately represent how much you exercise, you can also enter a custom level of activity using the “Activity Multiplier” option. This is mainly for people who do a lot of exercise, like triathletes. If you’re like most people, and you work out a few hours per week, stick with the default Activity Level options in the calculator.

Next, you need to enter your target weight, like this:

bmi weight loss calculator

You probably have a number in mind already, but if you aren’t sure how much you want to weigh at the end of your cut, you can use the calculator to figure that out, too.

As you adjust your goal weight, the calculator will also show you what your approximate body fat percentage will be at different body weights. 

A basic guideline is if you’re a man, you generally want to end your cuts around 10% body fat, and around 20% body fat if you’re a woman. 

So, if you aren’t sure what your goal weight should be, enter whatever number will put your body fat percentage at 10% (men) or 20% (women). 

For example, my body weight normally hovers around 195 pounds at 10% body fat, and if I wanted to get down to 8% body fat, some back-of-envelope math would suggest I’d need to lose just a few pounds and get down to 191 pounds.

The problem here is this assumes all of the weight I lose will be fat, which is never the case. 

Whenever you restrict your calorie intake, you also lose body weight in the form of glycogen, water, food mass, and connective tissue and other components of fat cells, which can make up a significant portion of your total weight loss.

And let’s not forget you can lose muscle when dieting, too.

All this is to say that each pound you lose through dieting isn’t exclusively body fat, and this means you need to lose more weight than might think to reach any given body fat percentage.

For example, from experience, I know I need to be closer to 187 pounds to be at 8% body fat, not 191 pounds.

The Legion Weight Loss Calculator takes this into account by assuming that about 25% of the weight you lose won’t be comprised of body fat.

And in case you’re wondering, this number comes from what I’ve read in the scientific literature and experienced myself many times with my own body and the thousands of men and women I’ve worked with over the years.

Practically speaking, this means that if you need to lose 10 pounds of fat to reach your desired body fat percentage, the calculator will assume you need to lose about 12.5 pounds of body weight to do that.

This adjustment for non-fat losses won’t be perfectly accurate for everyone, of course, but it’ll be more precise than making no adjustment at all.

Now it’s time to work out the duration of your cut. You can go about this in two ways:

  1. You can enter how many days you’d like to be in a deficit, and the calculator will tell you the date your cut will end and how many calories you should eat per day to reach your goal in the time frame you’ve specified. 
  2. You can enter the date you’d like your cut to end, and the calculator will tell you the number of days it’ll take to reach your goal and how many calories you should eat per day to reach your goal by then. 

And if you’re not sure how long you want to cut or simply want to go as long as it takes to reach your goal, you can tinker with the calculator to find a sweet spot that allows you to rapidly lose fat with minimal muscle loss.

For example, maybe you have a summer vacation coming up in a few months and thus know that you want your cut to last three months, so you enter 90 days for the duration or the date before you leave and learn it’s 90 days from today.

Next, the calculator shows you how large of a calorie deficit you’ll need to maintain every day in order to hit your goal weight by your goal date. 

As a rule of thumb, you don’t want to maintain a calorie deficit of more than about 25% for any length of time. If you do, you’ll lose weight faster, of course, but you’ll also struggle more with hunger, lethargy, and potentially muscle and strength loss as well.

As you’ll learn in the next section, the ideal size of your calorie deficit will also vary depending on how much body fat you have to lose. If you’re someone like myself, with very little body fat, then you’ll also need to maintain a smaller calorie deficit. 

That’s why I like to keep my calorie deficit in the range of 15 to 20%, or even lower toward the end of my cuts. Most people with slightly more body fat can maintain a deficit of closer to 20 to 25%, and you can use the calculator to make sure you stay in this sweet spot.

For example, let’s say you want to lose 7 pounds in 30 days, but the calculator says that would require a 30% daily calorie deficit, which is a bit too aggressive. 

You then adjust your goal to losing 7 pounds in 40 days, which brings the daily deficit down to 23%, which is more reasonable.

This can go in the other direction, too.

For instance, if you find you only need to maintain a calorie deficit of 15% to reach your goal weight in 60 days, you could reduce your cut to just 40 days and maintain a 20% daily calorie deficit. 

If you want to be even more precise, the calculator also computes the ideal size calorie deficit for losing fat without losing muscle. 

This is particularly useful for people who are already fairly lean and muscular and looking to get even leaner because there’s a limit to how much body fat you can burn every day before you start to lose muscle.

Thus, if you input targets that’ll require a daily calorie deficit that’s likely to cause muscle loss, the calculator will tell you how to adjust it to avoid this as much as possible, like this: 

extreme weight loss calculator

Likewise, if your targets are overly conservative and would have you losing fat slower than you could, the calculator will suggest you increase the size of your calorie deficit to lose fat faster without losing muscle, like this: 

weight loss calculator percentage

Now, while calorie intake is all you need to control if all you care about is body weight, if you want to focus on body composition, you need to go beyond just calories in and out.

Specifically, you need to also pay attention to how your daily calorie intake breaks down into protein, carbohydrate, and fat, generally referred to as “macros” (short for macronutrients).

The calculator makes this easy to do because it automatically translates your calories into a balanced diet of 40% of calories from protein, 40% from carbohydrate, and 20% from fat.

If you want to change these proportions for any reason, however, you can simply adjust things using the input fields or sliders.

And that’s it! You’re ready to begin your weight loss diet!

All that’s left is to use this information to create a meal plan you can stick to and you’re off to the races.

Summary: To use the Legion Weight Loss Calculator, enter your current weight, body fat percentage, and activity level, as well as your target weight and time frame. The calculator will then tell you how much to eat every day to reach your goal and whether or not you should make adjustments to ensure you don’t lose weight too slowly or quickly and sacrifice muscle. 

How Fast Can You Safely and Healthily Lose Weight?

There’s a limit to how much fat your body can metabolize (burn) per day before it gets serious about breaking down muscle for energy.

This is something bodybuilders have known for decades, but a study conducted by Professor Seymour Alpert at the University of New Mexico sheds light on exactly how fast you can lose fat before you start losing appreciable amounts of muscle.

Alpert parsed through data from previous weight loss studies that included measurements of body composition. Using several different mathematical models, he then compared how much fat and muscle the people lost at different levels of calorie restriction.

In other words, he analyzed how the size of the calorie deficit affected how much fat or muscle people lost while dieting.

This resulted in what Alpert believes to be the maximal threshold of calories (energy) the body can extract from body fat per day: 30 calories per pound of body fat per day.

We can use this formula to find how many pounds of fat you can lose per week before you have to worry about losing muscle.

To do this, first, find your body fat percentage. 

I’ll use myself as an example. I’m 195 pounds and based on the information in this article, I’m about 10% body fat.

Next, find how much total body fat you have.

To get this number, multiply your weight by your body fat percentage as a decimal.

195 x 0.1 = 19.5 pounds of body fat, which we’ll round up to 20 pounds.

Next, multiply your total fat mass in pounds by 30 to find roughly how many calories of fat you can lose per day before you start to lose muscle:

19.5 x 30 = 585

That means I can realistically maintain a daily calorie deficit of about 585 calories per day without losing muscle.

And to determine how many calories of body fat I could “safely” lose per week, I’d multiply the daily calorie deficit by 7:

585 x 7 = 4,095

And as there are about 3,500 calories in a pound of body fat, that translates to about 1.2 pounds of fat loss per week (4,095 / 3500).

What that means, then, I could expect to lose no more than around 1.2 pounds of body fat per week before I started losing significant amounts of muscle.

This neat little formula also explains why people with extremely high levels of body fatness are able to lose 3, 4, or even 5 pounds of fat per week while not just preserving but even gaining muscle. 

In some cases, these guys and gals are carrying over 100 pounds of body fat, so they can sustain much higher levels of weekly fat loss without losing any muscle to speak of.

For example, per the data we just discussed, if someone is carrying 100 pounds of body fat, they could theoretically maintain a daily calorie deficit of 3,000 calories (producing nearly 6 pounds of fat loss per week) and lose more or less no muscle.

(Actually doing this would be nearly impossible unless they’re extremely active, of course, but it’s food for thought nonetheless).

Other researchers (including Eric Helms, a member of our Scientific Advisory Board) have suggested the maximum weekly rate of weight loss should be 0.5 to 1% of body weight per week based on their current leanness, which falls right in line with Alpert’s research.

For instance, according to Eric’s model, I should shoot for about 1 pound of fat loss per week (0.5% x 195 = 0.975).

Now, it’s worth remembering that the studies Alpert reviewed to produce his findings weren’t conducted with resistance-trained people and in many cases, certainly included people who weren’t eating enough protein.

This means that those of us who work out regularly and eat enough protein might be able to lose slightly more fat before experiencing muscle loss, but it’s likely not much higher, as evidenced by Eric Helms’ recommendations.

Finally, it’s worth mentioning that none of what I just shared is dogma. The true test of whether your calorie deficit is too large or small is how you actually get on in your cut.

If you’re losing weight at a snail’s pace and you feel fine and are having great workouts and sleeping well, you can probably reduce your calorie intake slightly without suffering any negative effects.

On the other hand, if you’re losing weight at an “ideal” rate but are also struggling to get through your workouts and workdays, you probably should increase your calorie intake slightly.

Summary: The amount of fat you have affects how quickly you can lose fat without losing muscle. To maximize fat loss while minimizing muscle loss, aim to lose 0.5% to 1% of your total body weight per week when cutting.

Why You Need to Know How Many Calories to Eat

weight-loss-calculator-how-long

As you can see, this calculator revolves around calorie intake, because this is what determines your rate of weight loss and how much protein, carbs, and fat you should eat.

Why is calorie intake so important?

Because the relationship between the amount of calories you’re eating and burning (also known as energy balance) is the primary factor that determines your body weight.

Think of it this way: 

Imagine someone tells you that he wants to drive across the country without paying attention to his gas tank.

He plans on stopping for gas whenever he feels like stopping and pumping as much as he feels like pumping.

How would you respond?

I don’t know about you but this would probably be me:

You’re probably a nicer person than I am, though, so let’s say you just politely asked how he came up with such a plan.

Imagine this is his reply:

“I hate feeling like a slave to the oppressive fuel meter. I should be able to drive as far as I want before refueling and shouldn’t have to pay attention to how much I pump into my tank.

“Plus, I read this book that said you don’t have to watch your fuel if you use organic, gluten-free, low-carb, non-GMO, #blessed gasoline.

“It doesn’t clog your engine like other gasolines and burns more efficiently.”

Again, I don’t know about you, but this would be me:

And I would calmly gather up my toys and go play with someone else.

My point:

When someone says he wants to lose weight without having to pay attention to calorie intake or energy expenditure and instead focus on something else like food choices (“clean eating”) or meal timing (intermittent fasting), he’s missing the forest for the trees.

While it’s certainly possible to lose weight without watching your calories, this can only work for the same reason that calorie counting can work. 

What’s more, ignoring calories isn’t likely to work well over the long term because there are just too many ways to mess it up.

If you want to know how to lose weight efficiently and reliably, then, you want to know how calorie intake affects weight loss and gain, and you want to make sure this is working for and not against you.

And that requires that you understand a few things, starting with your basal metabolic rate.

Summary: Energy balance (calories in versus calories out) is the most important dietary factor when it comes to gaining or losing weight. 

Basal Metabolic Rate and Weight Loss

Your basal metabolic rate is the amount of energy your body burns at rest.

It’s the minimum amount of energy it costs to stay alive.

It’s called this because basal means “forming a base; fundamental” and metabolic means “related to the metabolism,” which is “the physical and chemical processes in an organism by which it produces, maintains, and destroys material substances, and by which it makes energy available.”

Unless you’re very physically active, your basal metabolic rate accounts for the majority of the energy your body burns every day.

That is, your basal metabolic rate burns more calories than your exercise and other activities. 

BMR is often expressed in calories, which are a measurement of energy.

One calorie is the amount of energy it takes to heat one kilogram of water one degree Celsius (also called a kilocalorie or Calorie with a capital “C”).

We can measure the amount of energy contained in food and the amount of energy our bodies burn in calories.

For example, I’m 35 years old, 6’2 and 195 pounds and my BMR is about 2,100 calories.

I say “about” because BMR calculation formulas like what you’ll find in this article and the calculator above aren’t 100% accurate for everyone.

That said, they’re accurate enough to be practically useful for diet and meal planning.

So that’s BMR. Simple enough.

And in case you’re wondering how the calculator determines your BMR, it uses a formula that’s based on your weight and approximate body fat percentage.

Now, the next thing you need to understand to control your body weight is your total daily energy expenditure (TDEE).

Summary: Your BMR is how many calories your body needs to burn to stay alive. 

Total Daily Energy Expenditure and Weight Loss

weight-loss-percentage-calculator

If you guessed that total daily energy expenditure refers to the total amount of energy your body burns every day, you’re right.

When you add up the energy burned by your basal metabolic rate (BMR) plus the additional energy burned through physical activity and the food you eat, you arrive at your TDEE.

You already know how BMR fits into this equation and everyone knows that physical activity burns energy, but many people don’t know that digesting and absorbing food costs energy too.

This is known as the thermic effect of food, or TEF, and research shows it accounts for about 10% of total daily energy expenditure, with amounts varying based on the foods you’re eating.

(Protein costs more energy to process than carbohydrate, and dietary fat costs the least amount of energy.)

Like BMR, the calculator in this article also shows you your approximate TDEE.

You calculate this by first determining your BMR and then multiplying it by a number based on how physically active you are.

(The more active you are, the bigger the multiplier.)

If you’re familiar with these types of formulas, you’ll notice that my activity multipliers are lower than what you normally see.

This is intentional because the standard multipliers that come with TDEE formulas like the Katch-McArdle are just too high.

They will likely overestimate your actual TDEE, which means you’ll either lose weight slower than you should or not lose any weight at all.

If you want to learn more about this, check out this article on calculating your TDEE.

So, now that you know what TDEE is, let’s move to the next piece of the puzzle: “macros.”

Summary: Your TDEE is how many calories you burn over the course of the day. This includes your BMR and calories burned through exercise, other activity, and the thermic effect of food. 

Macronutrient Intake and Weight Loss

weight-loss-calculator-calories

A macronutrient is any of the nutritional components of the diet that are required in relatively large amounts:

  • Protein
  • Carbohydrate
  • Fat
  • Water
  • Minerals such as calcium, zinc, iron, magnesium, and phosphorous.

(Most people think of “macros” as just protein, carbohydrate, and fat, but technically it includes the minerals as well.)

For weight loss purposes, the macronutrients you’re going to pay special attention to are protein, carbohydrate, and fat.

Let’s quickly review each.

Protein Intake and Weight Loss

If you want a strong, lean body that you can maintain with ease, then you want to make sure you’re eating enough protein.

There are quite a few reasons for this, but the are a high-protein diet . . .

Your protein intake is even more important if you’re exercising regularly because this further increases your body’s need for protein.

If you want to know how much protein you should be eating to build muscle and lose fat, check out this article:

How Much Protein Do I Need? The Definitive (and Science-Based) Answer

Carbohydrate Intake and Weight Loss

Ask Google how many carbs you should eat, weed out the idiots, and you’re left with a lot of contradictory answers.

Many well-respected health and fitness authorities argue why low-carb dieting is the way of the future.

Many others rail against it as just another fad.

Many still are in the middle saying “it depends . . .”

Well, here’s my position:

If you’re healthy and physically active, and especially if you lift weights regularly, you’re probably going to do best with more carbs, not less.

And yes, that applies to both building muscle and losing fat. The reality is a relatively high carbohydrate intake can help you do both.

This is largely because eating more carbs helps you maintain higher glycogen stores, which are beneficial for muscle growth for a number of reasons you can learn about in this article: 

What Every Weightlifter Should Know About Glycogen

And if you want to know how many carbs you should eat, check out this article to learn more:

How to Know Exactly How Many Carbs You Should Eat

Dietary Fat Intake and Weight Loss

Remember when low-fat dieting was all the rage?

When fat-free products flooded the supermarkets and fitness gurus used to say dietary fat made you fat?

Well, that pendulum has swung hard in the other direction.

Now we’re told carbohydrates are the real enemy and we should be eating copious amounts of dietary fat if we want to be healthy, lean, and strong.

What gives?

Well, the truth is dietary fat plays a vital role in the body.

They’re used in processes related to cell maintenance, hormone production, insulin sensitivity, and more.

If fat intake is too low, these functions can become compromised, which is why the Institute of Medicine recommends that adults should get 20 to 35% of their daily calories from dietary fat.

That said, those percentages were worked out for the average sedentary person, who often eats quite a bit less than someone that exercises regularly.

And even more so if that person has a higher than average amount of muscle mass.

For example, a 190-pound sedentary male with a normal amount of lean mass would burn around 2,000 calories per day.

Based on that, the IoM’s research says he would need 45 to 80 grams of fat per day. That makes sense.

Now, I weigh around 195 pounds . . . but I also have a lot more muscle than the average person and I exercise about 6 hours per week.

Thus, my body burns about 3,000 calories per day and if I were to blindly apply the IoM’s research to that number, my recommended fat intake would skyrocket to 65 to 115 grams per day.

But does my body really need that much more dietary fat simply because I’m muscular and burn a lot of energy through regular exercise?

No, it doesn’t.

Based on the research I’ve seen, as long as you’re getting at least 15 to 20% of your calories from fat, you’ll be fine.

Summary: Dietary fat plays a vital role in the body and doesn’t inherently make you fat. Ensure you get enough dietary fat by eating at least 15 to 20% of your daily calories from fat.

How to Use This Knowledge to Lose Weight

weight-loss-calculator-date

We’ve put three dots on a page:

  • Basal metabolic rate
  • Total daily energy expenditure
  • Macronutrient intake

Let’s now connect them and see how they relate to actually losing weight.

The first thing we have to review to do this is energy balance.

Energy Balance and Weight Loss

Energy balance refers to the relationship between the energy you feed your body and the energy it expends.

Yes, we’re entering “calories in vs. calories out” territory, but don’t worry–this isn’t our final destination.

It is, however, a necessary waypoint.

You see, the scientifically validated, “boring” weight loss reality is this:

Meaningful weight loss requires you to expend more energy than you consume.

A simple way to understand this is to imagine your body has an “energy checking account.”

  • If you eat more energy than you burn, you’re in a positive energy balance.

A positive energy balance causes body fat levels to rise because a portion of the excess energy is stored as body fat.

  • If you eat less than you burn, you’re in a negative energy balance.

And a negative energy balance causes body fat levels to fall because a portion of the energy deficit is filled by burning fat stores.

The real kicker for many people is the foods that provide the energy have little to do with this.

That is, when we’re talking weight gain or loss, what you eat isn’t nearly as important as how many calories you eat.

You can eat nothing but the “cleanest” foods but if you’re in a positive energy balance, you will gain weight.

On the other hand, you can eat nothing but gas station fare but if you’re in a negative energy balance, you will lose weight.

This is why Professor Mark Haub was able to lose 27 pounds on a diet of protein shakes, Twinkies, Doritos, Oreos, and Little Debbie snacks.

He simply ate fewer crappy calories than his body burned and, as the first law of thermodynamics dictates, this resulted in weight loss.

Now, if you’re shaking your head, thinking I’m drinking decades-old Kool-Aid, let me ask you a few questions.

Why has every single controlled weight loss study conducted in the last 100 years…including countless meta-analyses and systematic reviews…concluded that meaningful weight loss requires energy expenditure to exceed energy intake?

Why have bodybuilders dating back just as far…from Sandow to Reeves and all the way up the line…been using this knowledge to systematically and routinely reduce and increase body fat levels?

And why do new brands of “calorie denying” come and go every year, failing to gain acceptance in the weight loss literature?

The reality is a century of metabolic research has proven, beyond the shadow of a doubt, that energy balance is the basic mechanism that regulates fat gain and loss.

This is why claims that some foods are “better” than others for losing weight is misleading.

It misses the forest for the trees because foods don’t have any special properties that make them better or worse for weight loss.

What they do have, however, are varying amounts of calories and varying types of macronutrient profiles.

And a more accurate statement is the caloric content and “macros” of foods make them more or less suitable for weight loss.

The “best” foods for weight loss are nutritious and filling and relatively low in calories.

Examples of such foods are lean meats, whole grains, many fruits and vegetables, and low-fat dairy.

Foods more suitable to gaining weight are those that are high in calories but relatively low in satiety.

These foods include the obvious like caloric beverages, candy, and other sugar-laden goodies, but quite a few “healthy” foods fall into this category as well:

  • Oils
  • Bacon
  • Butter
  • Avocado
  • Sugar
  • Low-fiber fruits
  • Whole fat dairy products

Think of it this way:

You can only “afford” so many calories every day, whether dieting to lose fat, you have to watch how you “spend” them.

You want the majority of your calories to come from foods that allow you to hit your daily macronutrient and micronutrient needs without “overdrafting” your energy balance “account.”

Now, don’t mistake this section as me railing against eating healthy foods. Just because you can lose weight eating Pop Tarts, Doritos, and pizza rolls every day doesn’t mean you should.

Long-term health matters more than proving you can get abs on a TV commercial diet.

That said, if you have your diet set up properly, you don’t have to completely abstain from “unhealthy” foods, either.

Here’s a good rule of thumb:

Get the majority (~80%) of your calories from relatively unprocessed, nutrient-dense foods, you can fill the remaining 20% with your favorite dietary sins and be healthy, muscular, and lean.

Now, if you have to eat less energy than you burn to lose weight, how much less should you eat?

Summary: Losing weight requires maintaining a negative energy balance over time, and this is accomplished by consistently burning more calories than you consume. 

Calorie Deficit and Weight Loss

When you eat less energy than you burn, you’re placing your body in an “energy deficit.”

This is also referred to as a “calorie deficit.”

And the name of the game here is you want to keep your body in a large enough calorie deficit to significantly impact your weight…but not so large that you cause physiological problems.

For example, if you ate 50% of your TDEE, this would certainly reduce body fat levels, but it would also cause various problems.

Namely, muscle loss, metabolic adaptation, mood disturbance, and even bone frailty and immunosuppresion.

On the other hand, if you ate about 95% of your TDEE, you wouldn’t experience those negative side effects, but weight loss would be so slow that you’d eventually just give up.

Thus, the key is being aggressive enough with your calorie deficit to reach your goal without sacrificing your health or sanity.

Well, here’s my recommendation:

When combined with a high-protein diet and reasonable workout schedule, a calorie deficit of 20 to 25% allows for rapid fat loss without any negative side effects.

That is, if you eat 75 to 80% of your TDEE, balance your macronutrients properly, and use exercise to keep your energy expenditure high, you’ll do great.

And in case you’re wondering, I didn’t choose this calorie deficit at random.

It’s based on the findings of a study conducted by scientists at the University of Jyväskylä.

The study involved national- and international-level track and field jumpers and sprinters with low levels of body fat (at or below 10%).

The researchers split them into two dietary groups: a 300-calorie deficit (about 12% below their total daily energy expenditure) and 750-calorie deficit (about 25% below TDEE).

Both groups ate a high-protein diet.

And the results?

After 4 weeks, the athletes using a 300-calorie deficit lost very little fat and muscle while the group utilizing a 750-calorie deficit lost, on average, about 4 pounds of fat and very little muscle.

These findings are also in line with what I’ve experienced working with thousands of people.

A calorie deficit of about 20 to 25% is a good starting place for most people to lose about one pound of fat per week with little to no muscle loss and without feeling starved or deprived.

You may need to adjust this up or down based on your body fat percentage, but in my experience, it’s a good baseline.

Just remember the ultimate litmus test of the size of your calorie deficit is how well it’s working for you in terms of how you feel and how much weight you lose.

Summary: A calorie deficit of 20 to 25% is a good starting place for most people to enjoy rapid fat loss without any negative side effects like muscle loss or mood disturbance. 

How to Set Up Your Macros for Losing Weight

You now know a few of the most crucial things about effective weight loss:

  • You need to eat 75 to 80% of your TDEE.
  • You need to eat a lot of protein.
  • You will probably do better with more carbs than less.
  • You don’t need to eat a high-fat diet to be healthy.

The next step is learning how to turn all of this into daily macro targets that you can build a meal plan around.

How should you “spend” your calories in terms of macros?

Well, it’s pretty simple.

  • Set your protein intake to 40% of your total calories.

Unless you’re very overweight, this usually comes out to about 1.1 grams of protein per pound of body weight. 

  • Set your carb intake to 40% of your total calories.

This usually comes out to about 1.1 grams of carbohydrate per pound of body weight.

  • Set your fat intake to 20% of your total calories.

This usually comes out to about 0.25 grams of fat per pound of bodyweight, and gives your body what it needs for basic health purposes and leaves plenty of calories for carbs and protein.

One little caveat: 

If you’re sedentary, or have a medical condition like diabetes, then you’ll probably do better with fewer carbs.

In those cases, set your carbs to around 25% of your total calories. Keep protein at 40%, and get the remaining 35% from fat.

Summary: To lose fat efficiently, set your calories to 75 to 80% of your TDEE (as a starting point) and get 40% of those calories from protein, 40% from carbs, and 20% from dietary fat. 

Frequently Asked Questions About Weight Loss

weight-loss-calculator-calories-exercise

Should I “eat back” the calories burned from exercise?

No. 

The calories you burn from working out are already included in your TDEE calculation, which is what your calorie target was based on. 

So, if you eat more to compensate for the calories burned during exercise, you’d be reducing the size of your calorie deficit and thus slowing down your weight loss (or halting it altogether).

Additionally, estimating exactly how many calories you burn through exercise isn’t as simple as many people believe. It can be influenced by various factors, including your weight, age, experience level, etc.

You can’t rely on your fitness tracker or Apple watch, either, because it isn’t all that accurate in measuring how many calories you’re burning in your workouts, and particularly your resistance training.

So, at bottom, the smartest choice you can make for guaranteeing results is to use the Legion Weight Loss Calculator or a similar equation to figure out your ideal calorie intake to reach your goals and then just stick to it every day.

If you find you’re losing weight too fast or too slow, you can always adjust your calories up or down, but you shouldn’t worry about micromanaging your daily calorie intake based on your workouts.

Should I eat more on the days I work out?

Probably not.

There’s no great advantage to eating more calories on the days you work out versus eating the same amount every day. 

That said, if you’re an intermediate or advanced weightlifter, you might find calorie cycling more enjoyable because your body is more sensitive to a calorie deficit, so to speak, but most people don’t need to bother with this. 

Why am I not losing weight?

There are a few things that can cause this.

  1. You’re gaining muscle while losing fat. This is called recomping.
  2. You’re eating more than you think you are.
  3. You’re not burning as much energy as you think you are and are no longer in a large enough deficit to cause meaningful weight loss. 

If it’s number one, your body composition is improving, don’t worry about the lack of weight loss. 

Instead, focus on your measurements, how your clothes fit, and how you look. If you’re losing fat and gaining muscle, all of these things will be moving in the right direction.

If your body composition isn’t improving and you feel like you’re not making any progress, though, the solution is simple. 

To get the needle moving, you need to widen the gap between the amount of energy you’re burning and eating, and to do that, you need to either increase activity levels or reduce your calorie intake or both.

Two simple ways of accomplishing this:

  1. Add a session or two of HIIT cardio to your weekly regimen or even walk more throughout the week
  2. Reduce your daily calorie intake by 100 calories or so.

If you want to know more about what a fat loss plateau is, what causes it, and how to start losing weight again, read this article:

The Definitive Guide to Why You’re Not Losing Weight

How can I eat less without being hungry?

The easiest way to curb hunger when cutting is to make some simple changes to your diet. 

Assuming you’re eating plenty of protein, the following tips can help you control your appetite:

  1. Eat more fiber (and soluble fiber in particular).
  2. Drink more water.
  3. Eat fewer calorie-dense foods. This means eating less cookies, sugary drinks, oils, and fatty meats, and the like, and more vegetables, fruits, legumes, and lean meats.
  4. Get enough sleep.  

If you want to learn more about how to reduce your appetite, check out this article: 

8 Ways to Improve Hunger Control and Weight Loss

And listen to this podcast:

https://legionathletics.com/appetite-podcast/

I can’t eat this few calories. What should I do?

First, make sure you’re not losing weight too quickly. 

The only time you should be losing more than 1% of your body weight per week is if you’re very overweight (more than 20% body fat as a man or 30% body fat as a woman), or, if it’s the very beginning of a cut. 

It’s not uncommon for most people to lose several pounds per week during the first few weeks of starting a diet, but after this initial “whoosh” of fat loss, it should slow down.

So, if you’re losing more than 1% of your body weight per week, you aren’t very overweight, and you’re more than a couple weeks into your cut, you’re in too large of a calorie deficit.

Raise your daily calorie intake by eating 25 more grams of carbs per day and reassess over the next week or two.

If you’re losing weight at a reasonable rate, but it just feels like you’re not eating enough, make sure you’re following my previous tips on managing your appetite.

Beyond that, if you’re still dealing with issues with hunger and cravings, you can try exercising more and raising your calories to maintain the size of your current deficit. Sometimes the size of the calorie deficit isn’t the problem but simply the total amount of calories being eaten.

Now, if you’ve been cutting for many months, fat loss has plateaued, and you can’t increase your activity levels any further without running into issues related to overtraining (or for any other reason), try taking a diet break where you eat at maintenance calories for a week or two.

Then, go back to cutting and see how your body responds.

How should I count and track my calories and macros?

The first thing you’ll need is a food scale so you can weigh the foods you eat. 

While eyeballing portions is better than nothing, it’s too easy to mess up, and especially when you’re aiming for a moderate, relatively small calorie deficit.

From there, you can use a food database like SELF Nutrition DATA, the USDA Food Composition Database, or even CalorieKing or an app like MyFitnessPal, MyMacros+, or Cronometer to plan and keep track of everything you eat throughout the day. 

As far as planning in advance or tracking on the fly, I prefer the former because the latter quickly becomes a burden. You inevitably waste time debating over what to eat and working out how much you can eat and you increase the likelihood of mistakes, like forgetting to log every calorie or mistakenly logging more or less than you actually ate.

All of this is why I recommend you use a proper meal plan that ensures you can hit your calorie and macro targets eating the foods you like.

If you want to learn more about how to make an effective fat loss meal plan, check out this article: 

The Definitive Guide to Effective Meal Planning

Do I really have to count calories?

It’s possible to lose fat and gain muscle without counting calories, as all it requires is a calorie deficit and regular training.

That doesn’t mean it’s the most efficient way to improve your body composition, though, especially if you’re new to proper dieting.

The reason for this is simple: if you’re not carefully planning or tracking your calories and macros, it’s too easy to accidentally eat too much.

This is why people who take the time to create effective meal plans almost always make faster, more sustainable progress than those who try to wing it.

What’s more, often times when someone is able to successfully lose significant amounts of fat by just “eating intuitively,” they’ve spent a lot of time in the past carefully planning and tracking their food intake.

Thus, they’re already very familiar with how many calories they should be eating and how that translates into the various foods they like to eat.

And in some cases, these people often eat more or less the same foods every day and thus are essentially still following a meal plan.

That said, if you want to learn how to lose fat without following a meal plan or meticulously tracking your calorie intake, check out this article: 

How to Lose Fat without Following a Meal Plan [In 7 Steps]

The Bottom Line on the Legion Weight Loss Calculator

A good weight loss calculator uses your body weight, body fat percentage, and activity level to tell you how many calories and “macros” to eat every day to lose weight effectively.

It should also allow you to specify how long you’d like to cut and what you’d like to weigh at the end and then work out how much you’d need to eat every day to achieve that goal.

If your targets are too aggressive, the calculator should inform you of this as well and recommend an alternative approach.

That’s why we created the Legion Weight Loss Calculator. It does all that and more.

With it, you can set yourself up for long-term weight loss success by . . . 

  1. Giving you realistic expectations for how much weight you need to lose to reach your ideal body composition and how long it’s likely to take
  2. Ensuring you maintain an effective calorie deficit (not too big or small) and macro split (not too low or high in protein, carbohydrate, or fat)

So, all you have to do is follow the Legion Weight Loss Calculator’s recommendations in building your meal plan, stick to it, and your body will change.

If you liked this article, please share it on Facebook, Twitter, or wherever you like to hang out online! 🙂

What’s your take on the Legion Weight Loss Calculator? Have anything else to share? Let me know in the comments below!

 

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