Public health campaigns that highlight the dangers of obesity do not help fat people in losing weight, a new study has said.
Interviews with 142 obese adults found many felt stigmatised, shamed and blamed by government health campaigns.
The Cancer Council's ad linking increased waist size with a greater cancer risk was particularly disliked, said Dr Samantha Thomas of Monash University.
Positive campaigns, such Go For Your Life, which encouraged physical activity and healthy eating, were better received.
"The public health campaigns that people feel are stigmatising are often based on personal blame, personal responsibility and the assumption that if you tell people enough to lose weight, they will," News.com.au quoted Thomas as telling the Herald Sun.
"Unfortunately for most obese people, that just isn't the case. The causes of obesity are really complex and are not necessarily due to people being lazy, inactive and eating the wrong foods.
"They have not shown to be effective in reducing the prevalence or the level of obesity," she added.
Lilydale mother Elizabeth Sutherland, who was not involved in the study but readily concedes she is overweight, agreed with the study's results.
"The problem is that the campaigns stigmatise people. You are made to feel guilty about something that is already quite difficult - it can be quite hard living as a fat person in the community," she said.
Thomas said such campaigns often reinforced the public perception that all overweight people were unhealthy.
"They are based on the assumption that all people who are fat have, or will have, health problems, and that they will be a burden on the health system, which just isn't always the case," she said.
But Craig Sinclair, of the Cancer Prevention Centre at Cancer Council Victoria, defended the campaigns.
"We know that many people do not properly understand these risks, so we have an obligation to raise awareness of the strong link between cancer and obesity," he said.
The study findings were published in BMC Public Health.