The thyroid is a small gland in the neck that controls how the body uses energy. An underactive thyroid (hypothyroidism) can cause tiredness, weight gain, feeling cold and low mood, while an overactive thyroid (hyperthyroidism) can cause weight loss, a fast heartbeat, anxiety and feeling too warm.
Both conditions are usually diagnosed with a simple blood test and are generally very manageable — an underactive thyroid is typically treated with a daily replacement hormone tablet, while an overactive thyroid may be treated with medication, and less commonly, other treatments. If you recognise a cluster of these symptoms, it's worth asking your GP for a thyroid check.
Common questions
What does an underactive thyroid cause?
Tiredness, weight gain, feeling cold and low mood.
How is a thyroid problem usually diagnosed?
With a simple blood test. Both underactive and overactive thyroid conditions are generally very manageable once diagnosed.