Hi and welcome, I look forward to reading more of your posts. I'm not genetically well programmed for carbs (low production of salivary amylase) https://steemit.com/health/@kiwideb/my-dna-test-results-are-in-can-i-eat-carbs-or-not
I have been lowish, but not super low, carb for probably two decades. But despite that, my fasting insulin is very high and neither my doctor or I have been able to figure out why. My best theory is something I read about excess adipose fat actually secreting insulin as well, and that is the only thing that makes sense.
IF seems to help, but also seems to stress my adrenals, and I can only do 3 meals a day, not go down to 2.
What has helped me is water fasting. I can only do 3.5 days at a time (being a very much past menopausal woman) but that does seem to lower my insulin enough to get into fat burning mode. This year I did a 3 dayer at the start of the year and then transitioned to almost keto. I'm currently about 1500-1600 cals, P 30%, F 45%, C 25%, keeping net carbs under 70.