PCTs in England are failing to raise awareness of diabetes and its serious complications among the general public, according to a report by Diabetes UK.
The health charity also warns that more than half (53%) of PCTs do not have strategies in place to raise awareness of the condition.
Its report, Access to Health Services, says that one in three PCTs do not have a programme in place for the early identification of type 2 diabetes.
Diabetes UK estimates that 400,000 people in England have the condition but are not aware of it.
It also says that, of the PCTs that do have strategies in place to raise awareness of diabetes, nearly half (44%) do not differentiate between type 1 and type 2 and this will result in misleading and confusing messages.
Douglas Smallwood, Chief Executive of Diabetes UK, said: "Diabetes is one of the biggest health challenges facing the UK today. In the National Service Framework for Diabetes, the government set diabetes care standards and highlighted the importance of both early identification and prevention.
"PCTs have an important role to play in raising awareness of both type 1 and type 2 diabetes and informing people of how simple lifestyles changes, such as eating a healthy diet and being physically active, can help reduce their risk of developing Type 2 diabetes and can help the ongoing management of those already living with diabetes.
"Early identification is crucial, as people with type 2 diabetes can remain undiagnosed for up to 10 years, which puts them at increased risk of developing the devastating complications of diabetes such as stroke, heart disease, blindness and amputation."
There are currently 2.5 million people with diabetes in the UK, and it is estimated that if current trends continue by 2025, more than four million people will suffer from diabetes (both diagnosed and undiagnosed).