The most common thyroid symptoms in women are tiredness, weight changes, feeling unusually cold or hot, mood changes and changes to your periods. Which ones you get depends on whether your thyroid is underactive (making too little hormone) or overactive (making too much) (NHS underactive; NHS overactive).
Thyroid problems are more common in women. An overactive thyroid is about 10 times more common in women than men (NHS), and Hashimoto's disease, the main cause of an underactive thyroid in the UK, is most common in women and usually starts between 30 and 50 (NHS).
Key takeaways
- Underactive thyroid tends to cause tiredness, feeling cold, weight gain, constipation, low mood, dry skin and hair, and irregular or heavy periods. Symptoms usually come on slowly (NHS).
- Overactive thyroid tends to cause anxiety, irritability, feeling hot, weight loss despite a bigger appetite, a fast or irregular heartbeat and trembling (NHS).
- One symptom alone isn't enough to point to thyroid disease, and symptoms can be mistaken for menopause (NICE NG145).
- A blood test usually gives the answer (NHS).
Signs of an underactive thyroid
An underactive thyroid (hypothyroidism) slows many of the body's processes. The NHS lists these symptoms (NHS):
- feeling extremely tired
- feeling cold more than usual
- putting on weight
- constipation
- difficulty concentrating or thinking clearly
- low mood or depression
- dry skin, and dry hair or hair loss
- a croaky (hoarse) voice
- irregular or heavy periods
These usually develop slowly and get worse over time, so they're easy to put down to being busy or getting older. You're more likely to have an underactive thyroid if others in your family have had a thyroid condition (NHS).
Symptoms of an overactive thyroid
An overactive thyroid (hyperthyroidism) speeds things up. Symptoms include (NHS):
- nervousness, anxiety and irritability
- feeling hyperactive, with lots of nervous energy
- mood swings and difficulty sleeping
- feeling tired all the time
- sensitivity to heat, warm skin and sweating
- weight loss, often despite a bigger appetite
- an irregular or unusually fast heartbeat
- trembling or twitching
- diarrhoea, needing to pee more, and thirst
- itchiness, and hair loss or thinning
- a swelling in the neck, and eye problems such as redness, dryness or vision changes
It typically starts between the ages of 20 and 40 (NHS). About 4 in every 5 people with an overactive thyroid have Graves' disease, an autoimmune condition that mostly affects young or middle-aged women (NHS).
Underactive vs overactive thyroid: side by side
| Underactive thyroid | Overactive thyroid | |
|---|---|---|
| Energy | Extreme tiredness | Tired, but restless and full of nervous energy |
| Temperature | Feeling cold | Sensitive to heat, sweating |
| Weight | Weight gain | Weight loss, often with a bigger appetite |
| Mood | Low mood or depression | Anxiety, irritability, mood swings |
| Bowels | Constipation | Diarrhoea |
| Skin and hair | Dry skin, dry hair or hair loss | Warm skin, itchiness, hair thinning |
| Heart | Not a typical listed symptom | Fast or irregular heartbeat |
| Other | Hoarse voice, irregular or heavy periods | Trembling, neck swelling, eye problems |
| Main UK cause | Hashimoto's disease | Graves' disease |
Sources: NHS underactive thyroid; NHS overactive thyroid.
Thyroid, menopause and pregnancy
Menopause. Tiredness, low mood, weight gain, poor concentration and period changes can all be thyroid-related or menopause-related. NICE specifically cautions that thyroid symptoms in menopausal women may be mistaken for menopause (NICE NG145). Our guide to perimenopause symptoms covers the overlap.
Pregnancy. If you have an underactive thyroid and are pregnant or planning a pregnancy, tell your GP. Untreated, it can increase the chance of serious complications such as pre-eclampsia, premature birth or miscarriage (NHS).
Early warning signs in women
Thyroid problems rarely announce themselves. The changes that tend to come first are easy to attribute to something else — work, age, poor sleep, stress — which is why they're often missed for months.
The ones worth noticing early:
- Tiredness that rest doesn't fix, rather than ordinary end-of-week tiredness
- A change in temperature tolerance — feeling cold when nobody else is, or newly unable to stand heat
- Unexplained weight change without a change in eating or activity
- A shift in your periods, becoming heavier, lighter or irregular
- Hair and skin changes — thinning hair, dry skin, brittle nails
- Mood changes, particularly new anxiety or low mood with no obvious cause
None is specific to the thyroid on its own, and that's the point: it's the combination, and the fact they're new, that makes a blood test worth asking for rather than any single symptom.
The less obvious signs: hands, nails, legs and head
Thyroid symptoms get summarised as tiredness and weight change, but several of the signs people actually notice first are more specific and much less talked about.
Hands. An underactive thyroid can cause dry, cool skin and a feeling of stiffness or puffiness in the fingers. It is also associated with carpal tunnel syndrome, so new pins and needles, numbness or night-time tingling in the thumb and first fingers is worth mentioning rather than dismissing as a sleeping position.
Nails. Slow growth, brittleness, ridging and splitting are common with an underactive thyroid. Nails grow slowly, so nail changes usually reflect something that has been going on for months rather than weeks.
Legs and feet. Aching, heaviness, muscle cramps and a puffy, non-pitting swelling around the ankles and shins can all occur. Some people describe legs that feel weak on stairs before they notice anything else.
Headaches. An underactive thyroid can be associated with headaches, and the fatigue and disturbed sleep that come with it make existing headaches or migraines harder to manage. Headache alone is rarely a thyroid problem — but headache alongside several of the other signs here is worth testing for.
Hair and skin. Thinning hair, loss of the outer third of the eyebrows, and skin that has become dry and coarse are classic and often predate a diagnosis by a long time.
None of these is diagnostic alone. The reason to list them is that they are the ones most often put down to age, stress or winter — and a cluster of three or four together is a much stronger signal than any one of them.
Borderline and subclinical results
One of the most frustrating outcomes is a result described as "borderline" or "subclinical". It means TSH is outside the reference range while the thyroid hormone itself (T4) is still within it — the gland is working, but the pituitary is having to push harder to make it happen.
What usually follows is monitoring rather than immediate treatment. UK guidance is to consider repeat testing rather than act on a single borderline reading, because TSH fluctuates and a proportion of borderline results return to normal on their own (NICE NG145). Thyroid antibodies are often checked at this point, because their presence makes progression more likely and changes how closely you are followed up.
If you have been told your result is borderline and you feel unwell, that is a reasonable thing to keep raising. Ask what your actual TSH figure was, whether antibodies were checked, and when the repeat is due — and keep a record of symptoms in between, because a pattern over months carries more weight than how you feel on the day of an appointment.
Thyroid eye disease
Thyroid eye disease is most often associated with an overactive thyroid, particularly Graves' disease, though it can occur with normal thyroid function. The signs are distinct from the general symptom list: gritty, dry or watering eyes, redness, swelling or puffiness of the lids, a staring or more prominent appearance to the eyes, discomfort on looking up or to the side, and in some cases double vision.
Two things are worth knowing. Risks are greater in smokers, and stopping smoking is one of the few things shown to influence the course of it (British Thyroid Foundation). And any change in vision — particularly loss of colour vision, or double vision that is new — needs urgent assessment rather than a routine appointment.
Losing weight with an underactive thyroid
An underactive thyroid slows metabolism, and modest weight gain is a genuine symptom rather than an excuse. But two things are commonly misunderstood.
The first is that the weight gained is often less than people expect — typically a few kilograms, a good proportion of which is fluid rather than fat. A large weight change usually has other contributors alongside the thyroid.
The second is that once thyroid function is adequately treated and stable, weight management works in the ordinary way. It can feel harder, because fatigue makes activity harder to sustain, but the metabolic brake is released. If you are being treated and your results are stable yet weight is still climbing, that is a reason to look wider rather than to assume the thyroid dose is wrong.
Our guides to a safe rate of weight loss and eating with an underactive thyroid cover the practical side.
How thyroid problems are diagnosed
A blood test can usually show whether symptoms are caused by your thyroid (NHS). NICE advises that one symptom alone may not point to thyroid disease, recommends considering a test for people with depression or unexplained anxiety, and says not to test during an acute illness unless the illness itself may be thyroid-related, because it can affect results (NICE NG145).
Already have results? Our guide to thyroid blood test results explains what TSH, T4 and antibodies mean. For a broader look at your health, try our health check.
When to see a GP
See a GP if you think you might have an underactive or overactive thyroid, or if you notice a lump or swelling in your neck — our guide to thyroid nodules and enlarged thyroid explains what gets checked and when. It helps to write down your symptoms beforehand, as some overlap with other conditions (NHS underactive; NHS overactive). Also see a GP if you notice a swelling in your neck (NHS).
Call 999 or go to A&E if a neck swelling makes it hard to breathe, or you have a wheezing noise when you breathe (NHS).
If you'd like a clinician to look at your symptoms and results together, our thyroid service can arrange testing and explain what the results mean for you. If you are weighing up how to get tested in the first place, our guide to getting a thyroid test in the UK compares the NHS, private and at-home routes.
Honest FAQs
What are the first signs of thyroid problems in a woman?
Often tiredness, weight changes and feeling unusually cold or hot. An underactive thyroid tends to develop slowly, so early signs are easy to miss (NHS).
Can thyroid problems cause anxiety?
Yes. An overactive thyroid can cause nervousness, anxiety and irritability (NHS), and NICE advises considering a thyroid test for unexplained anxiety (NICE NG145).
Can an underactive thyroid affect your periods?
Yes. The NHS lists irregular or heavy periods as a symptom of an underactive thyroid (NHS).
At what age do women get thyroid problems?
Anyone can get one, at any age. Hashimoto's disease usually starts between 30 and 50, and an overactive thyroid typically starts between 20 and 40 (NHS; NHS).
Is it my thyroid or the menopause?
It can be hard to tell, because the symptoms overlap, and NICE notes thyroid symptoms can be mistaken for menopause (NICE NG145). A thyroid blood test can help sort out which is which.
This article is general information, not medical advice. Always speak to a qualified clinician about your own symptoms.
