Like a lot of you I've been taking Tonalin CLA to help firm up and it's really proven to be a miracle pill. But this past week while I was in florida I ended up having a horrible case of kidney stones. Extreme pain, vomitting. It was terrible. Well a week later I'm better and the stones have been sent to a lab. The results came back as the stones were made from proteins found in the CLA. My doctor demanded I stop taking the pills as a normal healthy 19 year old who drinks tons of water shouldn't have kidney stones. He said the pills would normally take about 6 months to a year to cause the stones. I was just unlucky. so PLEASE read this and take this into consideration if you're taking them. Talk to your doctor. Maybe I am just a freak but I want to make sure no one else goes throught the pain I did.