It is vital that those at risk are diagnosed early to prevent long-term organ damage, the charity says.
Type 2 diabetes can sometimes be put into remission by eating a healthy diet and keeping slim without needing to rely on glucose-lowering medications.
The researchers say newer obesity treatments – such as GLP-1 jabs and pills – might help, alongside healthy eating advice.
About 90% of the six million people in the UK living with diabetes have the type 2 form of the disease rather than type 1, or insulin-dependent, diabetes.
Risk increases with age and older adults still make up the largest proportion of new diagnoses.
But 12,000 people under the age of 30 are now living with type 2 diabetes, with women making up more of those younger cases, according to NHS England estimates, external.
The most common symptoms include feeling very tired, peeing more than usual and feeling thirsty all the time.
