According to the Centers for Disease Control and Prevention, weight loss is the result of following a simple formula. To get rid of excess body fat, all you have to do is “use up more calories than you take in. Since one pound equals 3,500 calories, you need to reduce your caloric intake by 500—1000 calories per day to lose about 1 to 2 pounds per week.” In other words, if you eat as many calories as you burn, you will maintain your weight, and if you tip the scale either way, your weight will fluctuate. But how do we know when we are in “energy balance?” How do we know how many calories we burn, or eat, and how do we know the estimates are precise enough to keep us in at or below our energy balance?

First of all, how is anyone supposed to know if they are eating 500 less calories every day? If you eat at a restaurant, how do you know how many tablespoons of oil are in the soup you ate? One extra tablespoon of oil is already an extra 120 calories. You can use various online tools to help you, but that implies that the portion size you are eating is the same as the one online, or that you can figure out the difference. A cup of pasta with a quarter-cup serving of alfredo sauce according to caloriecount.com is 320 calories(spaghetti, alfredo sauce) . If we change the portions slightly, to 1.2 cups of pasta with .4 cup serving of alfredo sauce, we end up cosuming 445 calories. Even the most experienced dietitian would have trouble determining if their lunch had these extra 125 calories in it.

One can argue that when you are on a weight loss diet, you should limit the amount of times you eat at restaurants and focus on home cooked or pre-packaged foods or places that offer nutrition information to make sure you know what you are eating. However this may not help either. According to an article in the New York Times, menus in fast-food restaurants or on the packages of frozen foods are sometimes not accurate. When researchers tested food served in 29 chain restaurants and 10 frozen meals, they found that their calorie contents averaged significantly more than was listed. Some differences were startling: Denny’s grits, listed at 80 calories, turned out to contain 258.

The Food and Drug Administration allows a 20% margin of variation in the calories listed to the actual calories. So that 390 calorie Lean Cuisine Jumbo Rigatoni with meatballs you just bought may allowably be closer to 470 calories, not to mention the recent findings that the discrepancy may be even larger. It seems nearly impossible to accurately maintain this recommended 500 calorie reduction.  Perhaps setting more measurable goals is in order.

We think there is value in using pictures to keep track of what you are eating.  PhotoCalorie can help you estimate the calories and nutrients you are consuming, while keeping a photographic journal as well, allowing you to set more concrete goals, such as ‘reduce the number of fast food meals per week from 5 to 2.,’ or ‘stop eating dessert on the weekends.’

There is no substitute for keeping track of your approximate caloric intake.  When setting goals, however, it might benefit you more to take measurable steps in directions that you can control.

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Larry Nutrition and Weight Loss