The following article is a quick step-by-step guide to estimate how many calories you should eat to lose weight, which is a question I’m asked all the time.
When someone says lose weight, I take it to mean “lose fat without losing muscle”, so the following takes that into account.
In order to lose weight, you must eat less calories than you burn. This is a scientific fact!
Here’s the basic equation to calculate many calories you should eat to lose weight:
Step 1: Calculate How Many Calories You Burn Per Day
Here’s a quick way to estimate your calorie burn:
The equations above assumes (1) you have a sedentary job, (2) you exercise moderately 3-5x per week and (3) your body fat is around 20%-25%. Don’t worry too much if you are not perfect with your estimate, just move to the next step.
Step 2: Determine Your Calorie Deficit Per Day
Many people will choose a random daily calorie deficit say 500, or 1000 calories, but I strongly recommend NOT doing this, because you can easily put yourself in starvation mode. Instead, choose a calorie deficit percentage range of 20%-35% less calories than your total calorie burn.
For example, take a guy who is 190 pounds and wants an aggressive calorie deficit to lose weight. He would take his total daily burn of 2,660 (190 pounds x 14) and apply a 30% calorie deficit, which would be 800 calories (30% x 2,660). His target calorie intake to lose weight is 1,860 calories per day (2,660 daily calorie burn – 800 calorie deficit).
Now if you multiply your daily calorie deficit by 7, you get your total weekly calorie deficit. Since 1 pound of fat has 3500 calories, you can estimate how many pounds of fat you can lose each week (usually 1-2 pounds) based on your weekly calorie deficit.
If these equations are starting to seem too complicated, a shorthand method to arrive at your target calorie intake to lose weight is multiply your bodyweight x 10 in pounds, or bodyweight x 22 in kilograms. You will arrive at a very similar number as going through these 3 steps. I think going through these steps, however, helps you understand the process of losing fat better.
Most health organizations recommend men don’t eat below 1,600 calories and women don’t eat below 1,200 calories, but keep in mind this is a law of averages approach. It really depends on how many calories you burn.
So how large of a deficit should you create? The leaner you are the lower your calorie deficit percentage should be (15-20%) whereas for people who have a lot of weight to lose, a 35% deficit could work well.
Step 3: Track Your Progress
In order to validate that you have estimated your calorie burn properly and are eating the right calorie level, we need a way to track your progress. I’m a big fan of tracking body weight with Monday Morning Weigh for all guys and women (depends on if you are comfortable). If you have any issues with weighing yourself, then monitor how your clothes are fitting.
Losing fat is more complex than simply “calories in and calories out” and establishing a target calorie intake. For optimal fat loss, you should also consider the quality of calories, timing of calories, and breakdown of calories (protein, carbs, and fat).
Finally, positive hormonal and metabolic changes from exercise can accelerate losing fat and have a HUGE impact.
Be Smart.