Practitioners and government officials agreed that improving education around diabetes is key to improving the situation.
They were giving evidence to the Health and Social Care Committee on 28 November 2012.
The committee is conducting an inquiry into the implementation of the National Service Framework (NSF) for Diabetes in Wales and its future direction.
Members of the Diabetes and Endocrinology National Specialist Advisory Group explained that education on the subject is "patchy" in Wales.
Julie Lewis, Diabetes Specialist Nurse Lead for Wales said that there are examples of good practice in some places that should be shared.
In the Deeside locality, after the initial diagnosis of diabetes, patients are immediately referred for a 2 1/2 hour session on how to deal with diabetes on a very basic level and how to change their way of life to deal with the condition.
After they understand their condition better, they are given a six week course for a few hours a week on a more expert level.
"It's trying to change the philosophy of what diabetes care should be," explained Ms Lewis.
Lisa Turnbull and Nicola Davies-Job from the Royal College of Nursing agreed.
"One issue specifically around nurses is capacity," said Ms Turnbull.
"If we don't have a sufficient number of nurses, we don't have the capacity to give education.
"When we looked into education, very much of the opinion was that it should be offered to everyone and we are convinced that it isn't.
"We had some opinion that the cost was discouraging Local Health Boards from taking it up.
"There seemed to be different opinion about what the barriers were.
"We would ask this committee to ask specific questions of local health boards why they're not delivering this program."
Professor Richard Roberts from Diabetic Retinopathy Screening Service for Wales also gave evidence as did the Chief Executive of the NHS in Wales David Sissling and Dr Chris Jones who is the Medical Director of NHS Wales.
Mr Jones said that education was "an area that concerns us".