A quarter of people in the UK object to diabetics injecting insulin in public, a survey said today.
A total of 42% of the 2,032 people questioned also said they thought eating too much sugar caused diabetes.
Diabetes UK, who conducted the myths survey to mark Diabetes Week which runs until June 19, said they were concerned by the findings.
Simon O'Neill, director of care, information and advocacy services at Diabetes UK, said the charity wanted to "destroy the myths".
He said: "Diabetes UK is appalled that some people object to injecting in public. For people who treat their diabetes with insulin, this is not a choice - insulin keeps them alive and injections have to be administered at specific times.
"People should be able to inject in public without fear of being mocked or shunned by those around them."
The Diabetes Myths survey also found 50% of those questioned think people with diabetes benefit from food and drink labelled "suitable for diabetics".
Mr O'Neill said: "We are calling for an end to the use of the terms 'diabetic foods' and 'suitable for diabetics' on food labels altogether.
"Diabetic foods have no extra nutritional value and are more expensive. Diabetes UK advises that people with diabetes have the same healthy, balanced diet as people without the condition."
The charity said diabetes was caused by a combination of genetic and environmental factors and sugar did not cause diabetes.
Mr O'Neill continued: "Sadly, we often hear of children who are bullied at school because their peers believe they've brought their diabetes on themselves from eating too many sweets.
"These sorts of myths are not helpful and can lead to discrimination and bullying.
"People with diabetes have a hard enough time living with their condition without being made to feel ashamed or different from their peers."
Mr O'Neill said other myths included people with diabetes could not drive, cannot play sport and Type 2 diabetes was "mild diabetes".
TV presenter Dominic Littlewood, who is supporting Diabetes Week, said: "Myths around diabetes are unhelpful and can be dangerous. As a person with diabetes I have heard many myths about the condition, including that diabetes is contagious - a complete untruth.
"I support Diabetes UK's efforts to dispel the myths around diabetes during Diabetes Week 2010."
A total of 25% of people quizzed objected to people with diabetes injecting insulin in public.
Adults in the UK were questioned for the survey last month.