If you have fatigue and weight gain, this could be a sign of a thyroid problem. I know this is yet another area where there is some controvery on the proper levels. However, I do think the standards were relaxed somewhat just recently...not sure. My neuro felt that my thyroid was what he considered "low normal." This was interesting, 'cause I went to an endocrinologist who insisted that they were fine. The neuro ended up giving me a small amount of Thyrolar. This has T3 and T4. I felt better and my hair stopped failling out. I don't have the exact link at the moment (and I'm rushing too), but if you go to www.about.com and look under "T" for Thyroid, there is a woman there who runs a good site/discussion on the topic. There are interesting articles there. I believe I have heard that Fish Oil, Flax Seed are some of the good supplements for Thyroid.