To lose weight and process insulin most effectively, we must recognize some simple truths about ketosis and carbohydrates. Nutritional ketosis is the default human state, and consuming mostly carbohydrates is the preparatory stage for fat storage now, so you can be in ketosis later.
When you spend more time out of ketosis than in ketosis, you will develop insulin resistance. However, more ketosis is not better — you need just enough that you are predominately using fat as fuel.
The debate should be what combination of healthy food and activity is necessary to achieve a predominant state of ketosis. Once we get to this debate, 2/3 of our current chronic health expenditures will magically evaporate.
Nutritional ketosis has been found to improve metabolic and inflammatory markers, including lipids, HbA1c, high-sensitivity CRP, fasting insulin and glucose levels, as well as aid in weight management. We discuss these findings and elaborate on potential mechanisms of ketones for promoting weight loss, decreasing hunger, and increasing satiety. Humans have evolved with the capacity for metabolic flexibility and the ability to use ketones for fuel. When we are eating low numbers of carbohydrates, insulin levels remain low and ketogenesis takes place. These conditions promote breakdown of excess fat stores, sparing of lean muscle, and improvement in insulin sensitivity.
Curr Nutr Rep. 2018 Sep;7(3):97-106. doi: 10.1007/s13668-018-0235-0.