# How Dieting Works

Building a Sustainable Diet

Photo courtesy USDA
The new USDA Food Pyramid.

Building a sustainable diet and exercise plan is the key to maintaining a consistent weight. This is not easy for many people. As described in the previous sections, the landscape is literally covered with calories, and exercise takes time and energy.

The first step to building a sustainable diet is to start counting the calories that you consume in a day so that you become conscious of two things:

• You need to understand exactly how many calories you are eating on a "normal" day.

• You need to realize where each calorie comes from -- you need to build a calorie database in your brain so that you know, whenever you eat something, just how many calories it is supplying.

In the United States, any food that you buy in the grocery store is required by the U.S. Food & Drug Administration to have a nutritional label with that food's calorie content. You can also look at a chart like this one to find out the number of calories in different foods. Any chain restaurant will supply you with nutrition information both at the store and on the Web (or you can see a Web site like this).

The second step is to figure out how many calories you need in a day. You can use the "12 calories per pound" rule, or you can get more precise by looking at the formulas in How Calories Work.

Pick your "ideal weight" -- the weight that you would like to maintain. Then calculate how many calories a day you can consume to maintain that weight.

The third step is to compare the two numbers -- You may be startled by the difference between the "number of calories you need" and "the number of calories that you take in" in a day. That is where the extra pounds are coming from.

The fourth step is to figure out how to bring the two numbers in line. What you will soon realize is that 1,600 or 1,800 or 2,000 calories per day just isn't that many. You have to watch and count everything you eat and drink every day and stick to your daily limit.

The fifth step might be to add exercise to the mix so that you can raise the number of calories you can consume per day. Online resources like this exercise calculator will show you how many calories different forms of exercise can burn. Burning 250 or 500 calories per day through exercise can make a big difference.