Hi, I am currently undergoing investigations regarding my thyroid function as recent blood tests have shown that I may have an under-active thyroid. This is not a critical illness, however it is a life-long illness and can have serious implications such as an increased risk of developing heart disease. I took out a joint life insurance policy last year so was wondering if I have to declare my diagnosis to my current policy holder if I am diagnosed with an under-active thyroid. I cant find anything in their T&Cs about this. Thanks!