Test one thing at a time. It feels slower and it is the only way to learn anything.

It gets smaller. Not easy, smaller. That distinction kept me going.

Worth repeating that this is not medical advice and the answer often depends on who you are.

Stupid question: how do you know whether what is in the vial matches the label at all?

This is the kind of post the forum exists for. Tolerance was my main issue with collagen peptides too.