A Calorie or kilocalories (kcal) is a unit of measurement given to the amount of energy your body generates from the food you eat.

The human body uses this energy for all our daily functions like breathing, talking, walking, digesting, our heat beat, and yes, exercise! So how many calories you consume can either help you or harm you. If you’re eating more calories than your body is using for energy it’s being turned into adipose tissue or in other words, stored as fat. And this happens whether you’re eating carbohydrates, protein or fat.

On the other hand, when you eat fewer calories than you expend your body taps into your fat stores and uses that for energy. This is called a calorie deficit. But having too big of a deficit can be harmful to your body and hurting you more than helping. In addition to tapping into your fat stores your body can also break down your lean body mass (muscles) as fuel and you definitely don’t want that. With that being said, it’s best to not let your calorie deficit fall below 500 calories a day.

There are many “calorie calculators” out there and your doctor or fitness guru will have them on hand, but Beachbody On Demand has a great formula to use, which is shown below:

If you want to maintain your weight, and you have a:

• Sedentary lifestyle (desk job): Current weight in pounds x 12 = Maintenance Caloric Needs

• Moderately active lifestyle (server in a restaurant and/or doing a 30-40min cardio exercise): Current weight in pounds x 13 = Maintenance Caloric Needs

• Highly active lifestyle (construction worker and/or doing a 50-60min cardio or work-out program): Current weight in pounds x 14 = Maintenance Caloric Needs

If you want to lose weight:

• Subtract 500 calories from your maintenance caloric needs (equation above), and that’s probably a good deficit for weight loss. But make sure that number stays at 1,200 or above. Anything lower can be dangerous in the long term.

If you want to gain muscle mass:

• Add 300 calories or so to your maintenance caloric needs (equation above) — but make sure you’re also doing a solid weightlifting program with a trainer or professional at-home workout program, so those calories have a place to go.

Your caloric intake number will probably range from 1300-2500 calories. Stay with your number in the beginning but if you have hit a stall or think it’s stopped working try tweaking the numbers. Decrease your calorie intake moderately; start by subtracting 200-300 calories from your current number. Try your new caloric number for a week to 10 days. If still no change, try increasing your calories to 200-300 for seven to 10 days. Sometimes we think were eating too much, when in reality we’re eating too little.

Calories are a necessity to survive so don’t look at them in a negative light. Your body needs fuel to survive just like your car needs fuel to go. Based on your activity level, figuring out the appropriate calories your body needs to burn energy is the key to weight-loss success and maintenance. However, there are good calories and bad calories so make sure you’re consuming the healthy, nutrient dense foods to best fuel your body. Even if a type of food fits into your caloric needs or as some say, “fits in your macros” doesn’t mean your body will use it the right way. Even though calories are necessary, remember that quality nutrition will always outweigh those necessary calories.