well your answer isnt related my question at all but i wonder where you doc gets your data from?
regarding diabetes there are to my knowledge 2 studies
1. study shows np effecr of finasteride on insulin sensitivity
„Dual inhibition of 5αRs, but not inhibition of 5αR2 alone, modulates insulin sensitivity in human peripheral tissues rather than liver. This may have important implications for patients prescribed dutasteride for prostatic disease.“
https://pubmed.ncbi.nlm.nih.gov/24823464/
2. compared patients (in average 70 years old and overweight) who got treated for prostata issues with finasteride (5 mg per day) and tamsulosin. from this study we can conclude that for the average 70 year old and overweight men there is a 0.16% higher chance of developing diabetes while being on finasteride compared to people who are not on finasteride (in numbers: from 1.000 70 year old men who are not on finasteride 60 men will develop finasteride in the next 10 years compared to 76 men who are on finasteride)
https://www.bmj.com/content/365/bmj.l1204
there are zero studies done young patients. but maybe your doctor knows more, idk