This is a question heard constantly. People with diabetes often feel a deep sense of injustice: "I eat simply, I never drink sweet drinks — how can I have diabetes?" The belief that "diabetes comes from eating too much sugar" is, in fact, one of the most common and persistent misconceptions about this condition.

Diabetes is not caused by eating sugar

Diabetes UK states plainly: "Eating any particular food does not directly cause type 2 diabetes."1 The University of Rochester Medical Center similarly explains: "Sugar does not directly cause diabetes — but consuming too much sugar, meaning too many calories, can lead to weight gain over time, which in turn raises the risk of type 2 diabetes. Diabetes is about the way the body produces or uses insulin."2

Put simply: diabetes is a problem with insulin — not a straightforward consequence of eating too many sweets.

What actually causes it

Type 2 diabetes develops from a combination of factors, many of which have nothing to do with sweet food:1

  • Genetics: Having a parent or sibling with type 2 diabetes raises your risk by two to six times.1
  • Age: Risk increases as we get older.1
  • Ethnicity: Certain ethnic groups — including East Asian and South Asian populations — face higher risk, and may develop the condition at a younger age.1
  • Weight and waist circumference: Excess fat around the abdomen reduces the body's ability to respond to insulin (known as insulin resistance) — the central mechanism behind type 2 diabetes.1
  • Physical inactivity: Being sedentary is an independent risk factor in its own right.1
  • Fat accumulation around the liver and pancreas: Even at a normal body weight, this can impair insulin function.1

Diabetes UK notes further: "Around 10% of people with type 2 diabetes have a BMI within the normal range."3 In other words — even if you are a healthy weight and have never been fond of sweet things, genetics and other factors can still put you at risk.

Does diet still matter?

Absolutely — but it is important to be precise about how. Diet influences risk, not direct cause. Regularly drinking sugary beverages, eating large amounts of refined carbohydrates, and consuming excess calories that lead to weight gain over time — these habits can indirectly raise the likelihood of developing diabetes.1 3 But "I ate a piece of cake and got diabetes" is not a logical chain of events.

For people already living with diabetes, the more meaningful role of diet is this: healthy eating habits help manage blood sugar, slow the progression of the condition, and improve quality of life. That is a separate question from whether diet caused the condition in the first place.