Hi everyone and welcome to The Ask Dr Cris Show. I often get asked, how do I know if I have an underactive thyroid? An underactive thyroid is quite easy to diagnose in a blood test, but some of the specific symptoms that you will pick up on if you have an underactive thyroid is weight gain, fatigue, your hair will thin, you may lose the outer third of your eyebrow, your skin can become dry, people find that they have difficulty in maintaining their weight. You can become a bit puffy and fluidly, you can have really heavy periods which are associated with an underactive thyroid. Some people notice a goiter or swelling in their thyroid in their neck region, other people don’t notice that. If it does run in your family, which often it does, or you have had a change like that and you think these things have been happening either suddenly or for some time it is worth a blood test for an underactive thyroid. Keep in mind an underactive thyroid you may tick all of those boxes and you will have a blood test and it doesn’t come back that is because lots of stress can make your thyroid appear as if it is underactive, and you will need a different test to test that – it is called reverse T3 which your local doctor can organise for you as well and that can be corrected also. If you have any of those symptoms and you think I think I have an underactive thyroid – I think my thyroid is running too slowly, I tick a lot of those symptoms in those boxes, then do hop along to your local doctor and have that tested.