Internal and external biases

The researchers used data that was previously collected from a 2018 study. The study involved 942 demographically representative English-speaking Canadian adults who completed questionnaires about attitudes towards weight-related issues.

Their secondary analysis looked at answers from three specific questionnaires that measured respondents’ internalization of negative attitudes about weight, their beliefs about the different causes of obesity and their explicit weight bias.

Among their findings, the researchers noted that internalization of WBI — the extent to which a person self-stigmatizes their own weight and applies negative attitudes towards themselves — was present in every BMI category (normal/underweight, overweight, obesity).

High WBI rates were reported in 20 percent of those who were normal/underweight, in 29 percent who were overweight and in 51 percent in the group of people who had obesity.

Respondents most commonly endorsed overeating as a cause of obesity (71 percent of the sample), followed by physical inactivity (67 percent) and high fat diets (59 percent) — all behavioural causes.

Among the least endorsed were endocrine disorders (35 percent), repeated dieting (38 percent) and metabolic factors (41 percent), which are physiological and psychosocial causes.

Beliefs in behavioural causes of obesity were directly associated with explicit weight bias, while beliefs in physiological and psychosocial causes were negatively associated.

“You tend to have more negative attitudes towards people with obesity if you really believe that obesity is mostly a behavioural issue,” Forouhar says.

Forouhar works as a research coordinator in the Montreal Interdisciplinary Laboratory on Obesity and Health. Her co-author Angela Alberga, an associate professor and research chair in the Department of Health, Kinesiology and Applied Physiology, is the lab’s director.

She adds that WBI has been linked to increased symptoms of depression, anxiety, psychological distress, eating disorders and exercise avoidance in many other studies.

“Our study reflects that weight bias is prevalent everywhere and among everyone, regardless of body shape and size,” she says.

“It does not only affect people with obesity. We should be addressing weight bias more systematically rather than simply from a clinical perspective.”

Iyoma Y. Edache (Concordia MSc 2019 alumna and current PhD student at the University of British Columbia) and Ximena Ramos Salas of Replica Communications also contributed to this study.

Les Fonds de Recherche du Québec-Santé provided funding.

Read the cited paper: “Weight bias internalization and beliefs about the causes of obesity among the Canadian public.”