Imagine that your body is a bank and that calories are the currency. The more calories you save, the fatter your account becomes. The more calories you spend, the less you save, the thinner your wallet will be.

To lose weight, we will need to go into calorie-debt. In order to do that, we will need to understand how to spend more calories than what would be normally available to the body for the day through our diet.

How Much Is Your Calorie Budget?
Your basal metabolic rate (BMR) is the number of calories that on a typical day you need to consume through your diet in order to maintain your current weight. The BMR is calculated based on height, age, weight, gender and lifestyle. Many free BMR calculators are available for free online, myFitnessPal for example.

Here is an example of how the calculation is done manually. To calculate the basal metabolic rate with a woman who is 42 years old, 5 foot 6 inches and 245 pounds with a sedentary lifestyle:
BMR = (height in inches)*4.7 + (weight in pounds)*4.35 - (age)*4.7 + 655
=                          (66)*4.7 +                          (245)*4.35 -  (42)*4.7 + 665
= approximately 1846 calories

In order to maintain her weight, our sedentary 42 year old woman should consume approximately 1846 calories a day. In order to lose weight, she will need to either spend calories or eat less.

What Spends Calories?
Everything. Imagine that everything that you do costs a certain amount of calories. Standing costs 50 calories per hour. Running costs 600 calories per hour. If you are on a weight loss plan, the more opportunities you take to burn extra calories, the better. Stand instead of sit. Park the car further away from the store. Take the stairs. Fidget. Do something extra.

How Many Calories Are You Eating?
Look at food labels. Look at the serving size. Measure the food. Track your daily calorie intake. Journal an your food for the entire day.

How Many Calories Should You Cut from Your Daily BMR to Lose a Pound?
In order to lose one pound you need to create a calorie deficit of 3500. That means that if your BMR is 1846 and you want to lose 1 pound per week, you will need to cut 500 calories per day, bringing your maximum daily calorie intake to 1346 calories.

How Do You Survive on 1300 Calories?
You don’t - at least not in a healthy way for very long. The more you exercise the more calorie debt you create. Adding an hour of cardiovascular exercise will allow you to eat more while losing weight.

Is There an App for that?
Yes! Free apps for the iPhone and Android like myFitnessPal and Lose It! are readily available, convenient and hassle-free ways to determine your daily calorie budget and track your nutrition throughout the day.

The great thing about many of these free Smartphone diet apps is that they display your calorie goals for the day based on your daily activity level. The more you move, the higher your daily calorie goal is. Most of these apps allow show you what you eat in terms of the nutrients that you consume, teaching you how to balance the amount of sugar, fat and protein you eat based on accepted nutritional norms.

The Moral of the Story?
Weight loss is easy. Calories in. Calories out. Exercise more. Eat smarter. And yes, for those who are not mathematically inclined, there is an app for that.