Why is issulin not in the course of treatment for all diebetics

For type 1 diabetes, insulin is required because of the beta cells in the pancreas are no longer making any insulin.

In type two diabetes, you might need it because the pancreas is worn to the point it no longer produces insulin.  

Explanation:

Type two does not always require insulin, and generally requires weight loss more than it does insulin, because insulin is usually still able to be produced, just maybe not as much as it should

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