How to Calculate "Calorie Deficit"

You've probably heard by now that if you want to lose weight, you have to eat in a calorie deficit. But what does that mean? Does it mean eating 1200 or less a day? That's what calorie trackers like MyFitnessPal told me. Does it mean restricting certain foods or entire categories of foods? That's what a low fat diet, or Keto diet, and many other types of diets do. 

I don't follow any specific diet, and only use a calorie tracker app every once in a while to calculate the calories in any new foods or recipes I'm eating. Following a moderation approach, eating nutritious foods I enjoy and treats, in a slight calorie deficit, has worked for me and my clients to lose weight. 

To calculate a true calorie deficit, most dietitians will use the Harris-Benedict Equation calculate BMR (basal metabolic rate), and then TEE (total energy expenditure), adjusting for PAL (physical activity level), and then subtract anywhere from 200 to 500 calories. It's a complicated equation, which is why I use this online Harris-Benedict Equation Calculator to determine my clients and my own Basal Metabolic Rate, Total Energy Expenditure, and adjust for Physical Activity Level. 

If you really want the exact equation, I'll write it out at the end of this post. 

In the meantime, this is how I use the online Harris Benedict Calculator

First, I plug in my numbers: 

You'll notice that my TEE (total energy expenditure) is 1,783 calories per day. 

This is how many calories I need to maintain my weight if I sat around and did nothing all day, but breathe and think. 

That is far more than 1,200 calories, and this isn't even adjusted, yet, for my PAL (physical activity level). 

PAL is how much I move during the day, AND any workouts I do. My job requires me to stand much of the day and do lots of walking on campus. I also take clients through fitness routines, in addition to my own workouts. So, let's adjust for PAL. 

Second, click the "Advanced Mode" to add in PAL: 

I strength train three to four days per week, and do cardio on the others days. This is in addition to all the activity in my job. 

Now my total calories per day necessary to maintain 135 pounds is 2,237! If you've dieted frequently, this may seem like a lot of calories. It's not. Our body needs energy and is hard-wired to fight calorie restriction. 

From this final number of 2,237, if I want to lose weight, I would subtract anywhere from 200-500 calories per day. Most of my clients want to start right away subtracting 500, the maximum amount, but remember, the body is hard-wired to resist calorie restriction, intentional or not, which is why diets don't work. 

I usually suggest starting by subtracting 250 calories per day. So, for me, that would mean I would eat 1,987 calories per day. The goal is to aim for consistent, steady weight loss, without binging because we've restricted too much. 

Will you calculate your TEE? Let me know how you do! 

Equation as promised: