I've replaced regular Cola with Cola Zero (yeah, I'm aware that it's not healthy as well but..) while keeping eating one or two candies while drinking black coffee and I've stopped gaining fat. Once I've started working out (running, ~5km, 1-3 times per week) and doing some pushups (nothing fancy, just 10 of them at the end of the day before shower) and here I am, one year later, feeling much better, with 13kg less :)

(before: ~93kg, now: ~80kg)