Weight control is just all about calories, right? Not so much! In fact, in my experience buying into that notion is one of the biggest barriers that hold my clients back from seeing results and optimizing their health. Here's the truth about calories and why letting go of counting them may be the best way to lose weight:

Myth: A Calorie is a Calorie

In the past few years, we've learned a lot more about how our bodies react to identical calorie levels from different foods. For example, one recent study found that saturated fats, like those found in butter, whole milk, and fatty meats, may override the body's natural satiety mechanism, whereas unsaturated fats, from plant sources like olive oil, avocado, and nuts, may enhance satiety- even when the calorie levels don't differ. A study from Wake Forest University found that even at the exact same calorie and fat levels, monkeys fed trans fat gained four times more weight and 30 percent more belly fat than monkeys given meals made with natural plant-based fats. A recent Penn State study found that over a 12-week period, dieters who consumed whole grains, rather than refined grains, lost more belly fat despite the diets being otherwise identical. This suggests that quality may be more important than quantity when it comes to the calories you consume.

Myth: Calorie Counts Are Always Accurate

By law, most products are allowed a 20 percent variance when it comes to the accuracy of the calories stated per serving. In other words, up to a 20 percent margin of error is acceptable, so if an energy bar states 250 calories it could actually contain 300. Just another reason not to get too hung up on exact numbers!

Myth: Counting Calories is the Key to Weight Control

A recent study from the University of California, San Francisco found that counting calories can actually backfire. The researchers randomly assigned 121 women to one of four diets: Group one tracked their calories, keeping them to 1,200 a day. Group two ate normally, but recorded the number of calories they consumed, Group three ate 1,200 calories a day, but did not have to record them and, Group four ate normally without any calorie-tracking.

At both the beginning and end of the three-week study, the researchers measured each woman's cortisol and stress levels. When calories were restricted, cortisol levels rose. In addition, calorie-counting (even without cutting) made the women feel more stressed out. Cortisol is a hormone that revs up appetite, spikes cravings for fatty and sugary foods, and leads to weight gain, particularly belly fat-and we've all been there when it comes to stress eating. This study supports the theory that there are physiological as well as psychological side effects to calorie constraint and counting.

Myth: Cutting 3,500 Calories = 1 Pound Lost

The formula ‘cut 500 calories a day to lose a pound a week' has been touted for decades, but it doesn't always work. In addition to the unwanted side effects mentioned above, subtracting 500 from your current calorie intake can mean you wind up eating less than it takes to support your ideal weight. This in turn could lead to loss of muscle mass and could slow down your metabolism, which makes it more difficult for you to lose weight and easier to gain it back. I never advise my clients to eat less than it takes to support their goal weight and activity levels. Sometimes that means cutting less than they think they should (e.g. not going on a 1,200 calorie diet), but it's actually more effective because the right type of weight is lost (fat, not lean tissue and fluid).

Bottom line: Don't disregard calories altogether, but focus on the balance, quality and timing of your meals and listen to your body. Not only is it freeing, it could just be the key to lasting results!


Cynthia Sass is a registered dietitian with master's degrees in both nutrition science and public health. Frequently seen on national TV, she's a SHAPE contributing editor and nutrition consultant to the New York Rangers and Tampa Bay Rays. Her latest New York Times best seller is S.A.S.S! Yourself Slim: Conquer Cravings, Drop Pounds and Lose Inches.