Understanding calories does a lot more for your body than the best training program.

“You can’t out-train a bad diet”

“Abs are made in the kitchen”

“Calories in versus calories out”

These staple mantras of fitness are repeated often, and with good reason-they’re true.

Before anything else, we have to understand why we eat. Food is many things-an integral part of ceremony,  representative of cultures and their histories, etc.,-but if nothing else, food is fuel. It is what gives energy to the machines that are our bodies.


This energy is accounted for through units called calories. Every day, just by existing, your body requires a certain amount of energy just to maintain itself. This number varies from each individual, and is affected by muscle mass, gender, and activity level. This number is your Basal Metabolic Rate.

To find your Basal Metabolic Rate (or BMR), there are several formulas available, but I prefer the Katch-McArdle Formula.

  • BMR=370+(21.6xLean Body Mass in KG)
  • Lean Body Mass = (Weight in KG x (100-(Body Fat)))/100

Your lean body mass is your bodyweight less the weight of your body fat. For example, I currently weigh 200 lbs and am 15% body fat. Therefore, I have 170 lbs of muscle.

My formula looks like this:

  • 370+(21.6×77.2)=2039

2000 is a miniscule calorie count for me, all things considered. I strictly adhere to it when I decide to get really lean, but normally, I stay at ~3,000 calories ( a little less than three Chipotle burritos) per day. So why, then, am I getting this BMR calculation of only a few thousand calories? Because I have yet to factor in my activity level. Katch-McArdle has recommended multipliers for your activity level, which you use against your calculated BMR. They are:

  • 1.200 = sedentary (little or no exercise)
  • 1.375 = light activity (light exercise/sports 1-3 days/week)
  • 1.550 = moderate activity (moderate exercise/sports 3-5 days/week)
  • 1.725 = very active (hard exercise/sports 6-7 days a week)
  • 1.900 = extra active (very hard exercise/sports and physical job)

I exercise moderately, all things considered, a few times a week, so:

2039×1.550=3,160 calories= Total Daily Energy Expenditure or TDEE

From there, decide what how aggressive you want your weight-loss to be.


 A caloric deficit is the amount of calories under your maintenance calories that you eat per day. When you are consistent over a period of time, eating in a caloric deficit is how you lose weight. For example, if you want to lose one pound per week, eat at a deficit of ~3500 calories (calories in one pound) over the course of the week. That’s only a deficit of ~500 calories per day. If you want it to be extremely aggressive (not recommended), take a 25-30% deficit from your TDEE. A more moderate and suggested choice is between 20-25%. If you have all the time in the world, start slow, at 15%, then gradually move into steeper deficits as your body adjusts.


This is meant to be a nutrition overview, not a thesis, so quickly and dirtily: calories are energy. Your body has different energy processing systems, which your body uses depending on what activity it is fueling. There are three types of fuel: proteins, fats, and carbohydrates. While there is no one-size-fits-all plan, most people’s bodies will function very well with more or less even distribution of all three fuels.

Micronutrients are things like iron, selenium, calcium, etc. If carbs, fats, and proteins are gasoline to your car, micronutrients are like windshield wiper fluid, fresh blades, and quality A/C coolant. Your ride is much more enjoyable with them than without them. They come from nutrient-dense foods. A nutrient dense food” are simply foods high in nutrients but low in calories. Most often, they are grown and not manufactured. 


Again, there is no one size fits all solution. Nutrition is unique to the individual, and a quality plan considers many variables. There are no “good carbs” and “bad carbs”. There are carbs that are slowly digested and carbs that are quickly digested. They are known as low-glycemic index and high-glycemic index carbs, respectively. You get fat when you consume more energy than your body needs immediately, and you are more at risk of doing this by eating high-GI carbs. These are sugars and processed foods. Generally speaking (again, quick and dirty overview), if it is lacking in color (bread/baked good) and/or sweet (fruit/gummy bear) it is high-GI.

Carbohydrates are the body’s preferred fuel source for intense activity. That isn’t limited to running sprints or one-rep maxes-your brain uses about a third of your daily calories, and it prefers glucose (the fuel that carbs are converted into).

There are several complex systems for converting carbohydrates into usable energy. Their respective usage depends on the intensity of the activity you’re demanding of your body.

TL;DR The worst carbs are too many carbs, and ones that come from processed foods and sugars. These are poison to your body. Carbs are very useful, but many people have great success in low-carb, high-fat nutrition plans. One plan will not fit all, and you have to experiment with what macros are right for you.


Mono-unsaturated fat-the kind found in steak, salmon, nuts, olives, and avocados-is extremely beneficial to your body. Your body needs fat to provide raw materials for many hormones (and regulate other hormone functions), and to provide fuel for low demand activities-sleeping, chilling, and other activities of leisure.


Calories are energy, and energy has to go somewhere. When you consume energy and don’t use it, your body stores it. Your body’s default storage setting is brown adipose tissue, also known as body fat.

Excess carbs, fats, and proteins get stored in different ways, but ultimately, caloric surplus results in fat storage.

It is as simple as that.


Protein is the brick and mortar of your body. When you ingest protein, your body breaks it down into amino acids. These amino acids make your body stronger through protein turnover. This is the process through which your body rebuilds itself. For example, when you put stress on your muscles and break down their tissue, it is the amino acids from protein that rebuild that muscle tissue through protein synthesis.

As with carbohydrate and fat intake, you determine your protein needs based on your goals and activity level. When you want to build muscle (and lose fat), you need to be training. In order to go through the aforementioned process, your body has to have enough amino acids available for building to be possible.

While high-carb/low-fat nutrition plans can work for some people, and high-fat/low-carb for others, the presence of protein is non-negotiable. Some schools of though prescribe 2 grams of protein per pound of bodyweight, others 1g per pound, and others .8 grams per pound. A good starting point is this method:

  • Eat 1g per pound of lean body weight (which you already know from calculating your TDEE).

While the number can seem daunting at first, it is easy to meet when you break it down into manageable portions. For example, say my requirement is 170 grams at 200 lbs and 15% bf. If I eat three times per day, that’s only about 60 g per meal. For reference, 1 pound of chicken contains about 130 grams.

A sample day of eating would look like:


Half-carton of eggwhites-50 grams

2 slices of bacon-12 grams

1/2 cup of oats


Spinach salad w/8 oz. of chicken and olive oil-65 grams



8-10 oz of salmon-50 grams

1 cup of sweet potatoes

Asparagus with olives/olive oil

This is a sample day that is low in carbs and higher in fat. Depending on your needs, you would add or remove carbohydrate sources, but understanding how to get adequate protein is the focus here.

TL;DR Caloric balance is king. Caloric deficit (less calories than you burn) is the only way to burn fat/lose weight; caloric surplus (more than you burn) is the only way to gain muscle/gain weight.

You can recomposition (stay the same weight, increase muscle mass and lose fat) by eating at maintenance calories and upping protein (and finding what carb/fat ratio works for you) and resistance training.

There are no good carbs or bad carbs, only too many.

Fat will not make you fat.

Calories are just units of energy, and you need to know how many you need.

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