Hello everyone. I'm so glad to have this forum to find out what this all means! I went to my GP last week as I've been getting daily palpitations and thought it might mean a heart problem. I'd put it off for ages as I don't like going to the doctors. Apparently I've got the above and have been prescribed 50mg of Levothyroxine. I wish I'd asked the following: if I am taking this medication do I need to change my diet too? My levels are: Serum Free T4 level = 10.6 pm/ol/L and the TSH level is 10.79. Does anyone know what that might indicate ie is it borderline, high etc. And my cholesterol was 7.4 mmol/L, HDL 2.3 and LDL 4.8. I would be very grateful for anyone who wouldn't mind giving me the benefit of their wisdom. Am I normal to feel a bit bewildered to be given this diagnosis when I had no idea I had a problem? Thank you all!