I don't specialize in thin fingers, but I use L 'Oré al slimming cream, apply it to my parts twice a day in the morning and evening, then make a fist and scrape it back and forth from bottom to top. I'm not sure if I've lost weight in about six months, but my fingers must have lost weight. I used to wear a ring with a size of 1 1, but now it's too big to wear a ring with a size of 10. Experience for yourself. You can try.