You want to be lean.
So you go on a diet.
You start exercising.
You lose weight at first, but then your progress slows. The scale stops dropping, the mirror doesn’t change, your clothes feel the same, and you’re not getting any leaner.
You’ve been eating less, but you’re not losing weight.
You’re confused, angry, and frustrated.
You begin to doubt your plan. You begin to question yourself and become desperate. You start looking at every supplement, every fad diet, every recommendation you can get your hands on. You’re frantic to lose fat — and you’re starting to freak out.
You’ve been through this scenario before. Every dieter has.
In this situation, you need to return to the fundamentals. You need to decide exactly what is going to help you lose fat — and what isn’t. Until you do, you’re going to stay stressed, miserable, and without the physique you want.
In this article, you’ll learn exactly what you can — and can’t — do to lose fat. You’ll learn exactly what you need to focus on and what you need to ignore.
As you’ll see, the answer is simpler than you might think.
Why Your Fat Loss Stalled
Energy In – Energy Out = Change in Body Stores (Weight)
The only way to lose weight is to create a negative energy balance — a caloric deficit.1-3
The way this formula is usually interpreted is as follows:
Eat Less + Move More = Lose Weight
Or in reverse…
Eat More + Move Less = Gain Weight
You’ve probably been disappointed by the “calories in versus calories out” approach before. You ate less and exercised more, yet you didn’t lose any weight or even gained some weight.
As hard and annoying as it is to hear, this is the truth:
You may have eaten less and exercised more, but you didn’t maintain a caloric deficit.
Why Eating Less and Exercising More Doesn’t Always Seem to Work
Weight loss is all about calories in versus calories out.
In practice, however, this simple process can be incredibly difficult for two reasons:
1. Restricting calories isn’t fun.
2. Both sides of the energy balance equation are variable.
You’ll learn how to make dieting suck less in later articles. For now, let’s focus on how your energy intake and energy expenditure can change as you diet.
The Energy Balance Equation is Variable
How much you actually eat and how many calories you actually expend can change over time, which can make it hard to predict how much you should eat or exercise to lose weight. This also makes it hard to predict your rate of weight loss.
This often leads to situations where people claim they are dieting hard, doing hours of exercise, and not losing weight.
That doesn’t mean dieting and exercise won’t help you lose weight — they will. You just have to understand that it’s not a linear process, or one that’s always easy to predict.
Let’s see why this is true. We’ll start with the first part of the equation — your energy intake.
Energy In: From Food to Body Fat
Imagine all of the food you ate yesterday arranged on a table.
If you were to put all of this food in a bomb calorimeter, burn it, and measure the heat that came off — you’d find the “gross energy” of your entire menu.1
Let’s say that’s 2,000 calories total.
As you’ve probably heard before, humans are not machines, and we process food a little differently than a furnace.
Let’s take a look at how much of that food is actually digested — and thus has the potential to become fat.
Gross Energy versus Metabolizable Energy
What you really care about is the metabolizable energy of your diet. That’s the number of calories that enter your bloodstream and have the potential to be used for energy.1
Determining exactly how many calories of metabolizable energy you consume is hard for three reasons:
1. People, including you and me, are never able to exactly measure how much food we eat. Even in a research settings where scientists weigh and measure every scrap of food people eat — they’re still estimating to a certain extent.
Most people are also terrible at remembering how much they’ve eaten, or estimating how many calories they eat per day.4-33 34-52 Even if you weigh all of your food to the gram and record everything — you’re still going to be slightly off.
Even if you were able to exactly measure your “gross” calorie intake, you still wouldn’t know how many of those calories may have the potential to be stored as fat. This is because…
2. You absorb different amounts of protein, carbohydrates, and fat, which can make it even harder to calculate how many metabolizable calories you’re eating.1,53,54
Most people absorb about 90-95% of the calories they eat. The rest gets excreted in feces and urine.55-64 However, this can change based on how much fiber you eat, how the food was processed, and your gut bacteria.1,54,56,58-61,65-78
3. Not all macronutrients have the same number of calories. Protein and carbohydrate have around 4 calories per gram, while fat has 9 calories per gram. This means that the kind of food you eat can significantly change the overall caloric density of your diet.67
While that seems fairly straightforward, different kinds of protein, carbohydrate, and fat have different caloric densities. For example, glucose — a kind of carbohydrate — has 3.692 calories per gram, while starch has 4.116 calories per gram — about 12 percent more.1
Luckily, you don’t need to know exactly how many calories of metabolizable energy you’re consuming for calorie restriction/counting to work.
Why You Don’t Need to Know Exactly How Much You’re Eating for Calorie Restriction to Work
You don’t need to know the specific number of calories that enter your blood stream. All you need to know is that to lose weight, that number has to go down. To make that number go down, you need to eat less.
What matters is your relative calorie intake. Even if your estimates are off by several hundred calories per day or more, as long as you consume fewer calories than you currently need to maintain your weight — you’ll lose weight.
Of course, this is assuming you’re smart about managing the other side of the energy balance equation.
Energy Out: Why Moving More Can Help You Lose Weight
There are basically two ways your body burns calories:
- Maintaining essential bodily functions.
- Fueling your movements.
Your total calorie expenditure is determined by the following five components:1,2
- Resting metabolic rate.
- Thermic effect of food.
- Thermic effect of activity.
- Non-exercise activity thermogenesis.
- The adaptive component.
Let’s take a look at each of these, and see which ones you can control, and which ones you can’t.
1. Resting metabolic rate.
Your resting metabolic rate is the combined total energy it takes to fuel your breathing, brain function, body temperature, blinking, immune function and all of your body’s essential processes. It’s roughly how many calories you’d burn while lying in bed staring at the ceiling all day.
Your basal metabolic rate is pretty much the same thing, except it doesn’t count little movements like blinking, yawning, scratching your head, etc. Basically, it’s how many calories you’d burn if you were in a coma, on your back, in a room about 75 degrees Fahrenheit.
Researchers usually use resting metabolic rate, since it’s harder to measure basal metabolic rate. Knowing your basal metabolic rate also isn’t any more helpful in most cases.
For most sedentary and lightly active people, about 60-80% of calories that are burned come from resting metabolic rate. Your resting metabolic rate is largely determined by your total body mass, lean body mass, gender, age, activity levels, and your genetics.79-87
There’s really not much you can do to change your resting metabolic rate. Gaining weight is one option — since you’d have more/larger cells to keep alive and move around, but gaining weight is obviously not your goal when it comes to fat loss.
Gaining muscle can help increase your resting metabolic rate, but the effect is minor. Fat tissue burns around 2 calories per day, while muscle burns about 6 calories per day at rest.88 To increase your resting metabolic rate by 200 calories per day, you’d have to gain 50 pounds of muscle. A lot of work for a small reward (in terms of increasing calorie burn).
Exercise tends to increase resting metabolic rate, but even then the effects are minuscule.
There’s some evidence that cold exposure can force your body to burn more calories to stay warm.89-95 However, there’s little evidence at this point that the effects are significant or meaningful over the long-term.
For the most part, your resting metabolic rate is determined by your genetics.83 However, the differences between people are still generally small. It’s rare for anyone to have a resting metabolic rate that’s more than about 15% lower or higher than average relative to their body mass. That’s generally going to be at most around 200-250 calories per day in either direction.
There’s really nothing you can do to increase your resting metabolic rate other than gain muscle, exercise, and maybe put up with being cold most of the time. Unfortunately, none of these techniques are going to make a huge difference.
You can also take anabolic steroids like testosterone or stimulants like ephedrine or clenbuterol, but these are generally not great long-term strategies.
Now let’s look at one of the most ironic aspects of energy expenditure.
2. Thermic effect of food.
Your body burns a fair number of calories digesting food.
After you eat, your metabolic rate increases as your digestive organs process your meal. This is referred to the “thermic effect of food,” or “diet-induced thermogenesis.”
Different macronutrients have different “thermic costs,” meaning you burn more calories digesting some macronutrients than others.96-98
Let’s say a food has a thermic effect of 20%. For every 100 calories you eat, you’ll burn an additional 20 calories digesting it.
The thermic effect of the four macronutrients are as follows:
Most mixed diets with a moderate intake of protein, fat, and carbohydrate have a thermic effect of around 10%, ranging from 5-15%.96
You can burn more calories by eating more or less of certain macronutrients, but the differences are small.
Protein has the highest thermic effect, and eating more protein can help you burn around 70-100 more calories per day.1,99-104
Alcohol has the next highest thermic effect, but there’s obviously a limit to how much you can consume, and not everyone enjoys alcohol.105 106,107 Alcohol also doesn’t have some of the other benefits of protein.
While carbs have a slightly higher thermic effect than fat, the difference is so small as to be meaningless in most cases.
If you replaced 500 calories worth of fat with carbs, you’d burn an additional 15-30 calories per day — hardly worth overhauling your diet. Studies have also shown that people who eat high- or low-carb diets lose the same amount of weight when their protein intake is identical. 1,3,108-110 High-carb diets sometimes have a slight non-significant trend toward greater energy expenditure,111, but other studies have found the opposite.112
Refined foods like cake or candy tend to be easier to digest than whole foods like vegetables, fruit, and meat, so they usually have a higher thermic effect as well. Once again, the difference is small (and certainly not worth giving up cake).
Exercise also tends to increase the thermic effect of food, although the effects can vary significantly between individuals.113
Some people burn more calories digesting food than others, but the differences are usually minor.96
Assuming you’re already eating a high protein/whole foods-based diet with plenty of fiber, there’s nothing you can do to change the thermic effect of food that will make any significant impact on long-term weight loss.
Now let’s talk about something you can control.
3. Thermic effect of activity.
Exercise is generally the most effective way to increase your energy expenditure.
Both strength training and cardio can burn a fair number of calories. In extreme cases, this can be massive. It’s common for highly trained endurance athletes to burn 800-1,000 calories per hour.114-121 For most people, 300-500 calories per hour is still doable without too much suffering.122-128
Harder and longer workouts also cause a greater rise in excess post-exercise oxygen consumption, also known as “EPOC,” or “the after-burn effect.” This occurs when your body works hard enough during the workout that your metabolic rate stays elevated afterwards, probably due to metabolic stress and increased protein turnover.129
Unfortunately, this effect is extremely small. For most steady-state cardio workouts, this will be about 7-8% of the total calorie burn. For intervals it’s closer to 12-14%. So if you did a 60 minute bike ride at a moderate pace, you’d burn maybe 500-600 calories during, and about 35-42 calories afterwards.129
Even if you were able to work at near maximal intensities for several hours, like riders in the Tour de France, this would only add up to a few hundred calories per day. Considering you could have burned around 4,000-5,000 calories during the workout, the “after-burn effect” is pretty minor. A nice bonus, but not significant.
Exercise of any kind is easily the most powerful thing you can do to increase your energy expenditure. It doesn’t matter what kind you do — just do something.
The problem is that most people don’t enjoy or don’t want to make time for lots of formal exercise, at least initially. Luckily, there are other ways to burn more calories throughout the day.
4. Non-exercise activity thermogenesis (NEAT).
This is a technical way of saying “all of the little movements throughout the day that don’t technically count as formal exercise.” This includes fidgeting, standing, changing your posture, scratching yourself, tapping your feet, pacing back and forth, etc.130-134
While none of these activities burn many calories by themselves — they add up. In some cases people can burn a staggering number of calories through NEAT.
In one study where people were overfed by 1,000 calories per day, some of the subjects produced enough NEAT to burn 600-700 calories per day.135
Here’s the downside. NEAT seems to be mostly subconscious and largely determined by genetics.
Everyone expends some calories through NEAT, but some people are genetically inclined to be far more active throughout the day without much — if any — effort.133 Generally, it’s the skinny ectomorph people who produce more NEAT, and part of the reason they’re skinny ectomorphs is because they burn so many calories through NEAT. Basically, the people who don’t need to lose weight are the ones who burn tons of calories with small subconscious movements throughout the day.
Depending on who you are, this makes NEAT one of the most frustrating or satisfying aspects of weight loss or weight gain. Some people fidget and move all day without using an ounce of will power, while others have to motivate themselves to get out of a chair.
How many calories you burn through NEAT also changes depending on whether or not you’re dieting. When you eat less, you tend to become more lethargic, your movements become more efficient, and you burn fewer calories through NEAT.136-138 This is true for everyone, but some people are much better at maintaining NEAT than others while dieting.
The opposite is also true. Some people are able to eat ridiculous quantities of food and barely gain any weight, while others gain fat almost in exact proportion to the number of excess calories they eat.135,139 Again, the former tend to be skinny people who don’t need to lose weight in the first place.
Here’s the good news: While you might not have the “skinny genes” that help some people stay lean, you can significantly increase your daily energy expenditure with small movements throughout the day.
It might not be effortless or easy, but it might be more convenient and less unpleasant than formal exercise. Here are a few simple ways to increase your non-exercise energy expenditure throughout the day:
- Use a standing desk.
- Park further away from buildings (so you have to walk further).
- Stand while talking on the phone.
- Pace back and forth while brushing your teeth.
- Stand while waiting for someone (doctor’s office, meeting, etc.).
- Bounce your legs while sitting.
- Stand in between sets at the gym.
These small actions can add up over time.
Now let’s talk about the last aspect of energy expenditure.
5. The adaptive component.
You probably know this by several different names:
“Major pain in the ass.”
The adaptive component represents all of the little adjustments your body makes while dieting to burn fewer calories. Dieting is a minor degree of starvation, and your body doesn’t like starvation.137,140-143
To keep you alive, it fights back against calorie cutting by making you burn fewer calories.
It does this by modifying the processes we just talked about:
- Your central nervous system output and thyroid and leptin levels decline, which reduces your resting metabolic rate.
- You feel more lethargic and fatigued, and you don’t recover quite as fast from workouts, which makes it harder to exercise.
- NEAT drops for the same reasons, sometimes by hundreds of calories per day.
This is true for everyone. The problem is that it can be far more severe for some people than others.
The same people who tend to have slightly higher resting metabolic rates, activity levels, and NEAT, also tend to maintain their energy expenditure better while dieting. As some researchers say, these people have “spendthrift metabolisms” — they tend to “waste” a lot of calories.
The people who usually have a lower energy expenditure also tend to have a larger decline in calorie burn when they diet.
You also burn fewer calories digesting food, since you’re eating fewer total calories.
What You Can — And Can’t — Do to Lose Fat
It’s easy to get overwhelmed and confused by fat loss.
There are thousands of options, gimmicks, and false promises that guarantee an effortless physique.
The truth is that these don’t work.
The only way to lose weight is to create a caloric deficit.
The two most powerful things you can do to create a caloric deficit are to eat fewer calories and burn more calories through exercise.
If you want to lose weight you have to eat less and move more.
Those are really your only two options.
You don’t necessarily have to count calories or start a formal exercise program, but your total calorie intake has to go down, and your movement levels have to go up.
In the next article in this series, we’ll take a look at some of the most common reasons people claim calories don’t count, and why they’re wrong.
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