Underactive thyroid (hypothyroidism) (NHS)

Tier 1: Established: peer-reviewed research or government health authority
Publisher: National Health Service · Published: August 8, 2026 · Accessed: August 8, 2026

Visit the source ↗

Claims this source supports

• Symptoms of an underactive thyroid include tiredness, weight gain, feeling cold, low mood or depression, and muscle aches, symptoms that overlap substantially with perimenopause fatigue.
• An underactive thyroid is more common in women and becomes more likely with age.
• It is diagnosed with a simple blood test (thyroid function test) and treated with daily levothyroxine tablets.