Diabetes mellitus is a disease where the body cannot control blood glucose concentration within normal limits.

It can occur due to lack of insulin production or failure of cells to respond to insulin.

Type 1 diabetes:

1. Occurs when the β cells in the islets of Langerhans produce no insulin
2. Typically begins in childhood
3. May be a result of an autoimmune response where the body attacks its own β cells

Type 2 diabetes:

1 Occurs when the β cells don't produce enough insulin or body cells don't respond properly to insulin

2 More common in adults, but starting to be more frequent in children

3 Largely the result of being overweight, excessive carbohydrate intake and/or physical inactivity

1. Regular insulin injections
2. Careful monitoring of diet and physical activity to control sugar intake
3. Islet cell transplantation

1. Managed or prevented by controlling the sugar intake in diet and regular exercise
2. Some medication may be used to make cells more sensitive to or produce more insulin
3. Insulin therapy may be used

Human insulin is now made using genetically modified (GM) bacteria.

1. Cheaper
2. Can produce larger quantities
3. More effective
4. Less likely to trigger an allergic response
5. Ethically preferred by some

In the past, insulin was extracted from animal pancreases, like those of pigs and cattle.

Stem cells are unspecialised cells that have the ability to develop into any type of cell.

Stem cells could be grown into β cells and implanted into the pancreas of a person with type 1 diabetes, enabling them to produce insulin.

The presence of glucose in urine can indicate diabetes because it shows that not all of the glucose in filtrate has been reabsorbed into the blood in the kidneys. This indicates that the blood glucose level exceeds a healthy threshold.