Thank you so much for your suggestions SAsaid go for what I feel comfortable and I am also scare of weight gain in the future that is the big concern for me. I'm in year round hot and humid weather country. However, I am also concerned about bracelet move around is it happen to you?
I also think the 17 looks like a great fit. Even if you put on some weight I don’t think it will be tight, as it looks like it has plenty of room. To me the 18 looks too loose but that’s my opinion and you are the one who will be wearing it, so you should go for what you feel comfortable wearing.
My wrist size is between 15-15.5cm, I wear a 16 juc and was sized to a 17 love and it’s more fitted than it is on you. However I have very small hands so the size 18 love bracelet sat very low on my palm and I really didn’t like the feeling, but it did look much better on my arm as it had more movement. This is partly why I haven’t brought it because I felt confused between the 2 sizes. So to me the 17 looks perfect on you, as it still has movement so it’s not tight nor loose.