From my reading of various research etc, metformin has some marginal beneficial effect to blood sugar levels, but it is not clear cut as perhaps you might think. In comparison, what IS undeniably effective is making simple lifestyle changes like going for a walk after a meal, not eating right before bedtime, doing some simple resistance training etc. These have much more measurable effects than metformin, with none of the potential downsides.

It’s on the World Health Organization list of essential medicines. 150M people rely on it to manage their diabetes. It’s been prescribed for 65 years.

Forgive me if I’m highly sceptical of your assertion that going for a walk after meals is an alternative to Metformin.

One needs to measure their HbA1c at home every few months to tell whether one still needs the prescription medicine. Seniors with low protein intake or low exercise will find that diabetes comes easily.

Obviously all processed carbs and red meat need to be cut out.

Vitamin B1 as thiamine is fairly important for glucose utilization. The benfotiamine form is additionally important.

There are just so many supplements for glucose regulation. I got my fasting glucose into the 80s by relying on psyllium husk and acacia fibers.

Ceylon cinnamon is good for post-meal glucose reduction.