As I understand it ketone production is perfectly natural and under normal circumstances quite safe and how our bodies should behave.
And it's a means to an end and not an end in itself. (A prime example is breast fed babies who live on a diet of fatty milk and are apparently in ketosis as a result).
Ketones only become an issue (i.e. ketoacidosis /DKA) if
- there is a severe shortage of available insulin (i.e. usually T1 or insulin dependent T2)
- glucose levels are very high
- ketone levels are very high
which results in an uncontrollable buildup of acids in the blood, which can cause coma and even death if untreated.
Our bodies were designed to work in a dual fuel mode using both carbohydrates (in the form of glucose) and fats for fuel, but with high carbohydrate diets while we can still
store carbs in fatty form but we appear to lose the abilty to
retrieve them as fuel. Carbs are short term, quick access fuel but since we can't store them in large amounts in easily retrievable form we need to top up regularly. But we have an abilty to store and retrieve vast quantities of fatty fuel, but can only access these if/when we're keto/fat adapted - and not relying all the time on our easy quick access carby fuel.
Eating a ketogenic diet (i.e. few enough carbs for a long enough period) will persuade our bodies back into being able to access stored fat again - we become keto or fat adapted. While it's generally recommended that going very low carb e.g. under 20-25g carbs a day to guarantee ketosis quickly, once we've "re-configured " it's not lways necessary to maintain this low level of carby consumption, so what we eat is entirely a matter of sensible low carb choices. Our meters will help tell how we manage this.
I've said previously I think many low carbers who lose weight and/or reduce glucose levels and maintain them, have plenty of energy, are not hungry all the time and have a decent level of mental clarity will be in ketosis whether they are aware of it or not.
And finally when we're properly fat adapted we may not be "in ketosis" all the time, we can pop in and out depending on different fuel levels and how or what we're actually eating or burning.
(Very strict ketogenic diets are used for therapeutic purposes - e.g. managing epiliepsy in children but we don't necessarily need to eat at this level to manage our diabetes.)
Robbity