I am a 16 year old female and for some reason I can't gain weight...and if I do, it's only about 1kg which soon I lose anyway.
Yes, I am eating, and I probably eat way too much which is why I am confused about this.
For some reason I seem to have to eat more throughout the day than anyone I know or else I will get really shakey and feel hot and dizzy.

My father has a history of an over-active thyroid and I wondered if I could have inherited it. I have had a blood test and everything was fine, completely normal.

I am very clueless of what is causing this.

Any advice? What other tests could be done to see if there is a problem?

Thanks