My mother and all of her sisters (4 of them) have thyroid problems and have been on medication for years. I started having symptoms that made my doctor believe it could be thyroid.
First of all, stop buying diet pills, supplements, drinks, and books. The pills and supplements can cause severe health issues if you mix the wrong things together not to mention they could cause weakening in the heart or damage. Seek medical advice first.
When I didn't get what I needed from my OBGYN I sought the advice from my family doctor who sent me to a specialist that deals only with diabetes and thyroid. They conducted an uptake test which requires you to have a dye shot (not painful at all and I am freaky about needles) in the arm that has radioactive material that passes through the veins to the thyroid and they x-ray you while the thyroid is in action. All my blood work and thyroid came up negative for problems.
I since then have pretty much diagnosed my issues along with my family doctors help as hormonal after having a baby 16 months ago. We are currently working together to resolve.
Watching my mother have such horrible weight issues and go on all the pills and diets I can tell you it's not going to work. There are also special doctors, once you have been able to take the uptake test for thyroid, which deals with nothing but weight loss. They can do blood work to determine your metabolism make-up, a healthy diet that will raise your metabolic rate to help your body burn more fat and calories, they test your heart and all your total body to make sure you are healthy and safe through the process, and can prescribe medicine if they deem it necessary to help with your desired results. Make sure you check into the weight loss doctor�s history before choosing one. I would go on google.com and type in the search field, �Choosing the right weight loss doctor� and see what pops up. Or ask your family physician to refer you to one.
I hope this helps. Good luck