Being overweight is not the cause of diabetes.
It is a common misconception that diabetes is caused by obesity. First of all, there are two types of diabetes. Type 1 is caused by an autoimmune disorder that destroys the cells in the pancreas that produces insulin. Type 2 diabetes is caused by cells being resistant to insulin Insulin is available, but it takes more insulin to produce the same effect. Type 1 diabetics tend to be skinny and type 2 diabetics are more often overweight. Because of this propensity to be overweight, people perceived obesity to be the cause of diabetes. Statistics indicate this is unlikely since the U.S. obesity rate is around 50% and the type 2 diabetes rate is just under 10%. I would expect that if diabetes was caused by obesity that the diabetes rate would be much higher. There’s a lot more to type 2 diabetes than weight alone.
The fact is that while excessive weight in type 2 diabetics can cause an earlier onset of diabetes, but it is not the cause. The cause is a genetic predisposition. The likelihood of type 2 diabetes lies deep in your genes. To develop diabetes you must be genetically predisposed and if you are predisposed, every inch of waist circumference your gain will increase your risk of developing diabetes type 2. Some are strongly disposed that they develop it despite being thin and staying thin only delays the onset in most of those with the genes.
The bottom line: Obesity and diabetes are linked but obesity is not the cause. While it’s true many people who have diabetes are overweight, there is not a causal connection.