A study by Diabetes UK has found Britain's poorest people were more than twice as likely to have diabetes than the average person.
The report said those living in the most deprived homes with the condition are also twice as likely to develop complications.
Obesity, physical inactivity, poor diets and smoking were all blamed for the increased risk of getting the disease - caused by the body not producing any or enough insulin.
The UK has more than 2.5 million people with diabetes, with the most common type being type 2 diabetes - which is often associated with lifestyle factors such as being overweight.
The study showed women in England who live in homes with the lowest income were more than four times as likely to get diabetes as those who lived in homes with the highest income. And diabetes in Wales was nearly twice as high in the most deprived areas compared to the least deprived.
Douglas Smallwood, the charity's chief executive, said deprived parts of the community should be targeted for disease awareness.
In particular, food labelling should be clearer so that people know what they are eating, he added.