Diabetes

Diabetes mellitus is a chronic disease characterised with abnormally high levels of the sugar glucose in the blood.

It is caused by failure of two of the body's functions:

- Inadequate production of insulin [which is made by the
  pancreas and lowers blood glucose]
- Inadequate sensitivity of cells to the action of insulin.

In type 1 diabetes there is no insulin or not enough of it.
In type 2 diabetes, there is generally enough insulin but the cells upon it should act are not normally sensitive to its action.

If left untreated, diabetes can severely damage organs in the body. Physical activity normalises blood glucose levels by making the body more responsive to insulin and increases the production of insulin. Studies have shown that people that exercise are 50% less likely to develop type 2 diabetes [Hara et al 1983].