How Ageing Changes Your Thyroid
Photo source: openverse, Diogo Miranda
Your thyroid is a small, butterfly-shaped gland at the base of your neck, and it quietly sets the pace for your body’s energy use. As we grow older, this gland can change in ways that are easy to miss. Knowing how ageing affects the thyroid helps you stay well and know when to talk to your doctor.
What Happens to the Thyroid With Age
Over time, the thyroid may shrink slightly and develop small lumps called nodules, which are common and often harmless. Hormone levels in your blood can also shift gently across the years. For many older New Zealanders, these changes cause no trouble at all.
Underactive Thyroid in Older Adults
An underactive thyroid, known as hypothyroidism, becomes more common with age, particularly in women. Tiredness, feeling cold, dry skin, constipation, weight gain and low mood are often put down to getting older, so the condition can go unnoticed for a long time.
Overactive Thyroid Can Look Different Too
An overactive thyroid, or hyperthyroidism, is less common but can be subtle in seniors. Instead of nervousness and sweating, older people may notice a fast or uneven heartbeat, unexplained weight loss, weakness or confusion. These signs overlap with other conditions, which makes them easy to overlook.
Why Thyroid Checks Matter
Thyroid problems can affect heart health, bone strength, memory and mood. A simple blood test arranged by your GP can measure your thyroid hormone levels and give a clear picture. If you take regular medicines, mention any new symptoms so your doctor can see the full story.
Everyday Ways to Support Your Health
You cannot prevent every thyroid change, but healthy habits help. Eat a balanced diet that includes iodine and selenium, as New Zealand soils are naturally low in both. Fish, eggs, dairy and iodised salt can help. Keep active, get enough sleep and attend regular health checks. Speak with your doctor before taking supplements, as too much iodine can be as unhelpful as too little.
Book an appointment if you notice ongoing tiredness, changes in weight or heartbeat, swelling in the neck, trouble swallowing, or a shift in mood or memory. Early checks make a real difference, and most thyroid conditions are very manageable with the right care.

