### Question
How is the term insulin defined?


### Answer
The term **insulin** is defined in *21 CFR § 200.15* as the following:

> the active principle of the pancreas that affects the metabolism of carbohydrates in the animal body and which is of value in the treatment of diabetes mellitus. 

#### Citation:
  - *21 CFR § 200.15*
  - Heading: **PART 200—GENERAL > Subpart A—General Provisions**

