Taken from the article
Overall, people who were overweight but not obese were 6% less likely to die during the average study period than normal-weight people. That advantage held among both men and women, and did not appear to vary by age, smoking status, or region of the world. The study looked only at how long people lived, however, and not how healthy they were whey the died, or how they rated their quality of life.
Why would overweight people live the longest?
Flegal and her co-authors suggest that it's possible that overweight and obese people get better medical care, either because they show symptoms of disease earlier or because they're screened more regularly for chronic diseases stemming from their weight, such as diabetes or heart problems.
There is also some evidence that heavier people may have better survival during a medical emergencies such as infections or surgery; if you get pneumonia and lose 15 pounds, it helps to have 15 pounds to spare, for example.
Do you think it's beneficial for people to be told that being overweight may help them live longer? Would you gain 15lbs if you thought it would help you live longer? Or slack off on losing the weight you felt like you needed to before hearing that?