Are you sick of drinking diet soda with your salad while your skinnier girlfriend gulps down supersize colas and cheeseburgers? You could blame your waistline on bad luck or bad genes, but the difference in your body shapes is more likely the result of your eating patterns.

A growing body of research suggests that most people who appear to be naturally slim actually share several characteristics that keep them from packing on the pounds. The good news? You can learn from their success. Follow these six easy tips to become naturally slim, too.

 

1. Low fat isn't necessarily better.

People who are thin often eat full-fat foods and drink regular soda, while dieters choose zero-calorie or reduced-calorie alternatives. However, foods with few calories that are sweet can impede the body's natural ability to judge how many calories a person consumes. One study shows that diet foods trick your body into believing foods sweetened with real sugar have no calories, which can lead to patterns of over-consumption.

2. Listen to your brain, not your cravings.

Lean people are less likely to eat immediately when they feel the urge. Food cravings, which can be triggered by familiar smells or fast-food commercials, are really just a temporary urge. With the exception of people who have diabetes and other-blood sugar problems, people can usually ignore their cravings by distracting themselves with another task. Try taking a walk, calling a friend, or reading. Thin people don't eat out of boredom.

3. Don't abandon the scale.

While diet experts once advised against weighing yourself on a daily basis, patients enrolled in the National Weight Control Registry prove that weighing yourself every day on the same scale helps people to lose weight and keep it off, according to Rena Wing, Ph.D., founder of the registry. She attributes the scale's effectiveness to the fact that people can catch small changes as they occur and take measures to correct the weight gain immediately.

 

4. Figure out what four ounces looks like.

People who have always been slim tend to have a better understanding of what portion distortion looks like. A study in the Journal of the American Medical Association found that when thin teenagers ate fast food, they automatically ate less than usual for the rest of the day, compensating for the extra calories from the fast food. Overweight teens, by contrast, ate just as much food as normal after eating the fast food, therefore consuming hundreds of extra calories.

5. Hit the snooze.

A good night's sleep is actually important for maintaining a healthy weight. Researchers at the University of Chicago studied healthy men and women who were allowed to sleep only four hours each night. After six days, the metabolisms of the sleep-deprived men and women were so irregular that their bodies weren't processing glucose in the blood in a normal manner.

6. Say later on instead of no.

Eliminating favorite foods from your diet can actually have adverse effects on your diet goals. People who sacrifice their favorite treats often wind up eating several other foods to replace the ones they gave up because they didn't feel satisfied. Most experts believe that it's okay to eat virtually any foodthe key is moderation. Treating yourself an occasional reward can actually be a practical way to limit your intake of your favorite junk foods.