Coarse hair and hypothyroidism

Hypothyroidism means the thyroid gland makes too little thyroid hormone. Lower hormone levels can slow activity in hair follicles and change the hair shaft, so hair may feel dry, rough, brittle or less full. A person with hypothyroidism may also notice fatigue, daytime sleepiness, constipation, cold intolerance, cold hands and feet, generalised weakness or a hoarse voice. These symptoms can overlap with many other problems, so coarse hair alone does not identify the cause.

Arrange a primary-care assessment if the change is new, persistent or accompanied by other symptoms. A clinician may examine your hair and scalp and request thyroid blood tests, usually including thyroid-stimulating hormone and thyroid hormone measurements. Mention recent illness, pregnancy, major stress, restrictive eating, new medicines, heat styling and hair treatments. Use gentle washing, conditioner and reduced heat while the cause is being assessed; do not start thyroid medicine or supplements without medical advice.

Seek prompt medical advice for sudden or marked hair loss, painful or inflamed scalp, patchy bald areas, or symptoms such as severe weakness, confusion, fainting, chest discomfort or breathlessness. These features need assessment because they may indicate a problem beyond ordinary hair dryness. If symptoms are mild but continue, book a routine appointment rather than relying on hair products to treat a possible thyroid disorder.

Ask whether your symptoms fit hypothyroidism, which thyroid tests are appropriate, and whether another scalp or nutritional cause should be considered. Ask when results should be reviewed and what changes would warrant an earlier appointment.