Being extremely overweight or underweight isn't healthy, but what about those few extra pounds that just keep hanging around? According to a new Canadian study published in Obesity, a little extra weight can't hurt...in fact, you might live longer. Researchers looked at the relationship between body mass index (BMI) and death over a 12-year period and found that people who were slightly overweight (defined as having a BMI between 25 and 30) lived longer than those of normal weight. While underweight people and extremely obese people were 70 percent and 36 percent more likely to die than people of normal weight, overweight people were 17 percent less likely to die than people of normal weight.

But since the study's focus is on mortality and doesn't include the health risks of obesity, researchers caution that people of normal weight shouldn't try to pack on the pounds. Dr. Madelyn Fernstrom, Today diet and nutrition expert, says, "The BMI is a guideline, and not a perfect number. More than a decade ago, a BMI of 27 was considered 'healthy', and with newer data is now considered overweight. That is an important observation: a BMI of 26 or 27, in the absence of health risks, can be a stable and healthy weight. Even a BMI under 30, if not connected to health risks like diabetes, high blood pressure, or high cholesterol can be more realistic for people to maintain."

Dr. Fernstrom's advice:

• Maintain a stable weight, rather than worrying about an elusive goal of a BMI under 25. (A BMI under 25 is very challenging for many people, and oftentimes not realistic).
  
• Talk with your doctor to determine if a BMI in the overweight range is a potential health risk for you.
  
• Current lifestyle and family history are both important factors, in addition to your BMI, when it comes to choosing a healthy weight.

The key to finding stability on the scale? Aim for a healthy lifestyle, without going to extremes. 

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