Obese people who feel stigmatised about their size are not only more likely to struggle with weight loss, they're also more likely to develop cardiovascular disease and metabolic disorders, a new study suggests.
In many cultures, people who are obese are viewed as stereotypically lazy, lacking in willpower, incompetent, unattractive and personally responsible for their excess weight, researchers note in the journal Obesity.
These negative beliefs, known as weight bias, can cause obese people to experience discrimination, which is in turn associated with an increased risk of "internalizing disorders" like depression, anxiety and low self-esteem, previous research has found.
For the current study, researchers focused on what's known as metabolic syndrome, a group of risk factors for heart disease, stroke and diabetes.
People with this syndrome typically have at least three of these five problems: excess belly fat, high triglycerides, low levels of "good" cholesterol, elevated blood pressure and high levels of sugar in the blood.
Participants who internalized weight-related stigma were 41 per cent more likely to experience metabolic syndrome than people who didn't internalize stigma very much, after accounting for depression and the degree of obesity, the study found.
"Experiencing weight stigma can elicit a physiological stress response, marked by elevated blood pressure and inflammation, and it's possible that self-directed weight stigma may be a form of chronic stress as well," said lead study author Rebecca Pearl, a psychiatry researcher at the University of Pennsylvania in Philadelphia.
"Individuals who internalize weight bias may also engage in unhealthy behaviours to cope with this stress - such as eating high-caloric comfort foods - which could affect triglycerides and other cardiometabolic risk factors measured in this study," Pearl added by email.
"Additionally, when people apply negative weight stereotypes to themselves, such as being lazy or lacking willpower, they have less confidence in their ability to engage in healthy behaviours, such as physical activity."
For the study, Pearl and colleagues examined data from lab tests for risk factors of metabolic syndrome and from questionnaires assessing weight stigma in 178 obese adults.
Overall, 51 people, or 32 per cent, had metabolic syndrome.
When researchers accounted for other patient characteristics in addition to depression and the degree of obesity, the connection between weight stigma and metabolic syndrome was no longer statistically meaningful, the study found.
The study was funded by Eisai Pharmaceutical Co., which sells a prescription weight-loss drug. One study author served on advisory boards for Nutrisystem, Weight Watchers and Novo Nordisk, a maker of diabetes treatments.
The study wasn't an experiment designed to prove how different levels of weight stigma directly cause metabolic syndrome, the authors note.
It's also possible that the results based on a group of patients participating in an obesity treatment study might not necessarily reflect what would happen with obese people in real life.
Still, discrimination clearly can cause chronic stress, which can result in biochemical changes that contribute to weight gain and inflammation that lead to abnormalities in blood pressure, blood sugar and cholesterol, said Dr. Kimberly Gudzune of Johns Hopkins University in Baltimore.
"It can start you down a pathway that increases your risk for cardiovascular disease," Gudzune, who wasn't involved in the study, added by email.
In part to avoid making feelings of discrimination and stress worse, doctors treating patients for obesity should choose their words carefully, said Dr. Anne McTiernan, a researcher at Fred Hutchinson Cancer Research Center and the University of Washington in Seattle who wasn't involved in the study.
"I would like people with obesity and their health care providers see the number on the scale as an indicator of health, just like their blood pressure," McTiernan added by email.
"The goal with excess blood pressure is to get the number down, not to subject the patient to shame. Similarly, let's treat the number on the scale as a measure of health risk, and help the patient get the number down effectively and safely, and help them avoid gaining the weight back."