What is hypothyroidism?
Hypothyroidism occurs when your thyroid gland — a small butterfly-shaped gland in your neck — doesn't produce enough thyroid hormone. Thyroid hormones regulate your metabolism, so when levels are low, everything slows down.
It's much more common in women than men, and the risk increases with age. The most common cause in Australia is Hashimoto's thyroiditis, an autoimmune condition where your immune system attacks the thyroid.
Symptoms to watch for
Symptoms of an underactive thyroid can be subtle and develop gradually: persistent fatigue, unexplained weight gain, feeling cold, dry skin, hair thinning, constipation, low mood, brain fog, and heavy or irregular periods.
Because these symptoms overlap with many other conditions — including iron deficiency, perimenopause, and depression — thyroid function is often checked as part of a broader investigation when women present with these complaints.
Diagnosis and treatment
Hypothyroidism is diagnosed with a simple blood test that measures TSH (thyroid-stimulating hormone) and free T4. Your GP may also test for thyroid antibodies to check for autoimmune thyroiditis (Hashimoto's).
Treatment is straightforward: a daily tablet of levothyroxine, a synthetic thyroid hormone that replaces what your body isn't making. It can take a few weeks to feel the full benefit, and your GP will monitor your levels and adjust the dose as needed.
Related condition
Thyroid health →References & sources
- 1.Hypothyroidism — healthdirect
- 2.Thyroid gland — healthdirect
- 3.Thyroid gland — Better Health Channel
This content is general information and not a substitute for individual medical advice. Please consult a GP for your personal situation.
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