A new study found that overweight women who believe negative messages about their bodies are at greater risk for heart disease and diabetes than those who maintain a more positive body image.
The research, published in the journal Obesity, showed that higher levels of "weight-bias internalization" -- the term for what happens when people are aware of negative stereotypes about obesity and apply those stereotypes to themselves -- were associated with more cases of metabolic syndrome, a combination of health issues that raise the risk for heart disease and diabetes.
This was true above and beyond the effects of body mass index (BMI), indicating that internalization isn't just a result of weight or other issues, but a risk factor on its own.
"There is a misconception that sometimes a little bit of stigma is necessary to motivate people to lose weight," says lead author Rebecca Pearl, PhD, assistant professor of psychology in psychiatry at the University of Pennsylvania's Perelman School of Medicine. "But time and time again, research shows that this is just not the case."
The new study supports the idea that when people feel bad about themselves, it can affect their physical health as well as their mental health, Pearl says.
To study this effect, Pearl and her colleagues at Penn's Center for Weight and Eating Disorders focused on 159 obese women who were enrolled in a clinical trial to test the effects of weight-loss medication. (The study was funded by the drug's parent company, Eisai Pharmaceutical Co.)
To determine their level of weight-bias internalization
, the women indicated how strongly they agreed or disagreed with statements such as, "I hate myself for being overweight." The statements touched on stereotypes about overweight people being lazy, unattractive, or incompetent.
The women were also examined to determine whether they had metabolic syndrome, which includes risk factors like high triglycerides, blood pressure, and waist circumference.
After the researchers adjusted for age, gender, race, and BMI, they found that women who scored in the top half for weight-bias internalization were three times more likely to have metabolic syndrome that those in the bottom half. They were also six times more likely to have high triglycerides, one aspect of high cholesterol.
The findings were also adjusted for depression, which is also associated with poor self-esteem and negative body image.
Most of the women in the study were African American. That's important, says Pearl, because most weight-bias research to-date has included mostly white women. Internalization scores do tend to be lower for black women, Pearl says, "but that doesn't mean it's doesn't affect some African Americans just as it affects white people or Hispanic people."
The study was not able to show a cause-and-effect relationship, and Pearl says it's also possible that people with more health problems feel worse about themselves as a result. But previous research helps support the researchers' theory that bias can have a direct impact on health.
It's been shown, for example, that fat-shaming experiences can lead to increased inflammation and stress-hormone levels in the body. People who feel bad about their bodies are also less likely to exercise, Pearl adds, and can have a harder time eating healthy.
It isn't clear why some women internalize weight bias and others don't, Pearl says -- whether they're in a supportive environment and exposed less to fat shaming, or are simply less vulnerable to its effects. But for many women, she says, these messages are hard to avoid.
"People with obesity are portrayed in negative ways in the media; there's bullying at school and on social networks; people even feel judged by family members or in health-care settings," she says.
It's important for loved ones, and the general public, to be sensitive to this issue, Pearl says. "Rather than blaming and shaming people and being dismissive of their struggle, we need to work collaboratively to set goals to improve health behaviors."
As for women and men who are struggling with their own body image, Pearl recommends taking a good look at the stereotypes they've internalized -- and then challenging them.
"If you know that you're not actually lazy and unmotivated, don't let yourself get sucked into to those negative thoughts," she says. Setting specific, achievable goals for improving health behaviors can also help, she adds. "It can help give people the confidence they need to really make a change."