I assume Type 2 Diabetes?
A1c of 4.8% is in the normal (as in non-diabetic) range.
You have lost 115lbs and from what you say seem to be eating low-carb?
How many grams of carbs per day?
How close are you to your ideal weight?
Insulin Resistance is associated with excess weight and so can improve (i.e. less need for insulin) as your weight is reduced.
Low-carb also means less need for insulin.
When you say "quit all diabetes medicine" does that include the insulin?
Are you going Hypo or do you feel OK at 60mg/dl? Is that a fasting BG? What is your 2 hour post-prandial reading like?
I hesitate to use the word "cured" - as I suspect that if you ate the way I presume you did previously (high-carb?) all this work could be undone - but maybe you have got this beast under control
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My last A1c was 5.0% and although I still use an insulin pump I only have basal insulin and never need a bolus with meals as I am also eating low-carb and am losing weight (about 50lbs down since August). I still have a fair bit of weight to go but I am hopeful that either I will be off injected insulin or at worse may get by with just a single daily injection of Lantus or similar... only time will tell. My total daily insulin is down from around 130u earlier this year to around 30u units today.