I have been taking them for months, there are no known side affects. They stop your body from absorbing fat and it comes out with your stools lol, you don't get diarrhoea though. They have helped me loose a stone on slimming world, obviously slimming world was a factor but I would loose 3lbs a week and when I had a bad week I still would loose! They supposedly suppress your appetite too. If you look on amazon or eBay you can get some good stuff, do a bit of research on them first as you need 1000mg of garcinia Cambogia extract each day I think, it's a fruit so it's natural.