If your weight goes up and down then maybe it's a concern?? Where do you gain weight? I've pretty much always been the same size, but when I have gained a few pounds, it doesn't show in my arms/wrists.
Have you tried the bracelet yet? When I tried them it it seemed clear that the 16 was the right one. I think if you try them both, you'll know!
I think it's more that my wrists sometimes swell with the heat.
I've tried the 17 on but not the 16. I honestly think I'm going to go for the 16 (order online). I like the loose look but realistically don't want it banging around all over the place.