@Mugnika @Tfmonkey few things to try
Low carb mainly leafy greens with fiber no or low carb content
Fasting be it long or short like one meal a day or two meals a day
Another thing is carnivore where you eat meat and fat. To change his insuline resistence
How To Reverse Insulin Resistance? – Dr.Berg he focus on keto and fasting
https://youtu.be/cUXSPIi5mE0?si=CMKA0Z9NA9aTibDK
Reversing Type 2 Diabetes and Insulin Resistance
https://youtu.be/t0AXL88cbjc?si=AgloDQhteJQv-6lu
Family Physician Dr. Berry for carnivore
https://www.youtube.com/@KenDBerryMD/videos