We all know that obesity can lower our quality of life and increase our risk of developing heart disease, stroke and certain cancers. But who suffers the worst in terms of lower quality of life?

A recent study finds that obese women suffer the worst.

Researchers from Kaiser Permanente Center for Health Research in Portland, Oregon, analyzed survey data from 3,844 U.S. adults ages 35-89 in hopes to gauge their physical and mental quality of life. The survey asked questions about mobility, pain, cognition, "vitality," anxiety and depression. Overall, researchers found that people with "normal" body mass index (ranging from 18.5 to 24.9) reported better health-related quality of life than overweight (BMI of 25 to 29.9) or obese (BMI of 30 to 50) people. But that's not all. They also found that obese women suffer a lower quality of life than women in terms of mental health.

The authors wrote: "Although there has been some emerging evidence that obesity may be negatively associated with mental health among women in non-U.S. settings, our analysis is the first to indicate that such an inverse relationship may be significant among American women, while confirming evidence that among men, the association appears significant only with physical health."

So why do women suffer more than men?

The study's researchers seem to believe that there is more bias and stigma for women to be obese than it is for men. Just last year a study came out finding that obese women earn less than obese men (but the pay gap between gender exists obesity or not).

Strange enough, when the researchers looked at race, they found that African-Americans who were just overweight cited better quality of life than those who were obese or of normal weight. Researchers weren't sure why and admitted that more research needed to be done to find out. My guess is that perhaps our cultural perceptions that having a few extra pounds is normal and not that big of deal may mean that we are less stressed and less anxious about it.

Yet whether we know it or not, it's important to recognize that extra weight can negatively impact our lives, including our teenagers. This past April researchers from the Centers for Disease Control and Prevention found that obese teen girls were more likely to have tried cigarettes or smoke regularly than girls with a healthy weight. They also found some serious sexual risky behavior among the obese teen girls surveyed.

"Our findings would suggest that teen girls who are extremely obese are less likely to have had sex — [that] was not surprising, but what was concerning was the fact that if they were sexually active, or had been sexually active, that it was more likely to be under the influences of substances," lead researcher Meg Zeller of the Cincinnati Children's Hospital Medical Center told CNN. "So it really paints this picture of vulnerability for this sub-population of teen girls and it really makes us question what their social interactions are really like."

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