Admittedly, I’m on a fairly low dose (500mg x 2), but I can still kill a bag of Haribo when the mood hits. It doesn’t , quite as often, but I’ve noticed no changes in flavor.

Thanks for the anecdote. Biological variation, we're all different!

Can you point to any studies around this?

I've never heard of this effect (let alone experienced it).

I do know that Diabetes itself can reduce the efficiency of taste receptors, and metformin will sometimes cause people to have a metallic taste in their mouth (due to metformin in produced saliva)

It's easy to find studies connecting metformin to weight loss and loss of appetite. I'll leave that to you.

Just use Google if you want anecdotal examples of changes in the response to food (changes in palatability and taste), for example:

https://forum.diabetes.org.uk/boards/threads/loss-of-appetit...

or

https://www.diabetes.co.uk/forum/threads/anyone-experience-l...

>Metformin changed the taste of food slowly during the time I took it. It finally got to the point where all vegetables tasted like burnt plastic. This meant that I didn't want to eat them.

And so on.