Dear Mary, I was so scared of not going anywhere on synthetic T-4 that I felt I had to make a maajor change. Iwas suffering beyond belief! My symtoms were so bad, and so bizzare, that my doctor couldn’t believe I was feeling THAT BADDLY! Well when you feel like holding a gun to your head, that doesn’t sound much like a great endorsment for synthetic T-4 now,does it? I out of shear dessperation twisted my drs. arm and begged for a trial on the natural, he agreed, as till this point in time, nothing else had helped. The very first pill I took, was like someone thew on a switch. The rest is history. I’ll NEVER take synthetic T-4 as long as I’m alive! The natural is so vastly superior it’s like night and day. It will not mess up your heart if taken properly. I was suffering from congestive heart failure and this stuff fixed that problem in short order! I can’t say enough good about this oldie, but goodie! Mary, GO FOR IT, You have every thing to gain, and nothing to loose! Good luck, and I’ll say a prayer for ya.