Explain the cause of type 1 diabetes and how it is controlled

The idea

Type 1 diabetes is caused when the pancreas does not produce enough insulin, usually because the insulin-secreting cells have been destroyed. Without sufficient insulin, blood glucose is not lowered effectively after eating, so it can remain dangerously high. Control involves injecting insulin, typically before meals, so that blood glucose is brought down. The amount and timing of insulin injections are matched to food intake and activity, and blood glucose is monitored regularly, often by testing blood. Diet and exercise are also managed to keep glucose within a safe range. A useful method is to link cause to control: damaged insulin-producing cells → insufficient insulin → high blood glucose → insulin injections plus monitoring restore control.

What earns the marks

• Type 1 diabetes is caused by the pancreas not producing enough insulin, often because the insulin-producing cells have been destroyed.
• Without enough insulin, blood glucose is not lowered effectively and can become too high.
• Blood glucose is monitored regularly and diet and exercise are managed to keep glucose within a safe range.

Common mistakes and how to put them right

• Saying type 1 diabetes is caused by cells no longer responding to insulin.

  Put it right by stating that in type 1 the pancreas does not produce enough insulin.

• Saying type 1 diabetes is controlled by diet alone.

  Put it right by stating that insulin injections are needed, supported by monitoring, diet and exercise.

• Confusing type 1 with type 2.

  Put it right by stating that type 1 involves insufficient insulin production rather than reduced cell response to insulin.

Exam tips

• State the cause clearly: the pancreas produces too little insulin.
• Link control to insulin injections and explain that dose and timing are matched to food and activity.
• Mention monitoring of blood glucose and management of diet and exercise as part of control.