While excessive sugar consumption is definitely not good for overall health, it does not directly cause diabetes.
Diabetes is, in fact, a complex metabolic illness, influenced by various factors including genetics, lifestyle and overall health.
There are two major subgroups of diabetics, type 1 (T1D) and type 2 (T2D).
T1D is an autoimmune disease in which the body’s immune system turns against, and destroys, its own pancreas, leading to a progressive loss of the insulin-releasing β-cells.
Diets high in sugar-sweetened beverages and unhealthy foods can contribute to weight gain, which in turn increases the risk of T2D
T1D most commonly starts in children and adolescents, and treatment is always with insulin. A genetic trait associated with the human leukocyte antigen (HLA) class II region explains approximately 50 per cent of the genetic background of T1D.
In contrast, T2DM, the more common form, is largely associated with being overweight or obese and having a poor diet. Apart from β-cell failure, there is also decreased sensitivity of fat and muscles to released insulin, often called insulin resistance and which is already present in the pre-diabetic stage.
Diets high in sugar-sweetened beverages and unhealthy foods can contribute to weight gain, which in turn increases the risk of T2D. However, individuals with a balanced diet and healthy lifestyle can also develop T2D due to genetic predisposition or other unknown factors.