Yes insulin is involved in regulating ketones. https://en.wikipedia.org/wiki/Ketosis Edit: inaulin is used, but not necessarily used up. The brain and nervous system cannot use fat as a fuel but muscle cells can, So ketones replace glucose in powering the brain during ketosis and get used up. Ketones that are not burnt up get excreted in the urine, sweat and breath. In diabetic DKA the ketones do not get burnt up because our bodies have a preference to burn glucose instead, so fats and ketones do not get burnt when there is ample blood glucose around, and thus build up to dangerous levels.