I’m a GP – these are the signs your thyroid isn’t healthy

Many a patient I’ve met in practice has been frustrated by their weight – or more specifically, by their apparent inability to lose it. Weekly trips to Slimming World for months on end, conscientious efforts with diet and exercise, yet still struggling to shift more than a few pounds. All well and good to be told from all directions – including by know-it-alls like me – to stick to the recommended plan. But much harder when you have zero energy, your mood has flatlined, your concentration has gone to pot, and simple decisions seem like baffling ordeals. Add in cravings for something comforting to eat, and suddenly maintaining that routine becomes out of the question. These are experiences we observe frequently in general practice, sometimes in patients who may have put up with them for years. But these symptoms can be interconnected, rather than just standalone problems – all stemming from the same underlying issue: an underactive thyroid gland. Shorts I’m diagnosing thyroid conditions more often these days, perhaps because there is greater awareness of their sometimes subtle features – and because thyroid function is more readily tested for a wide range of symptoms, including depression, weight changes and tiredness. It most commonly affects women too – they are five to six times more likely to develop a thyroid condition than men. Thyroid conditions often develop slowly and stealthily, and can easily fly under the radar. Changes may be subtle at first: weight creeping on that won’t budge – or waking from a full night’s sleep to find you’d be quite happy to head straight back to bed again. And it isn’t just the body that can slow down. The effects can also show up in the brain – affecting mood, concentration, and memory. For some people, cognitive and emotional changes are the symptoms they notice the most; feeling mentally slower, struggling to find words, losing track during conversations, or feeling generally spaced out – all encompassing that increasingly familiar complaint we’ve come to describe as “brain fog”. Learning a little more about what the thyroid gland does – and why its hormones matter to our brains as well as our bodies – can make these symptoms easier to recognise, and perhaps harder for us to dismiss. Finding your thyroid The thyroid gland is roughly the shape of a bow tie, and located more or less where you’d expect to wear one – in front of the neck, wrapping round the windpipe. It takes instructions from another gland, the pituitary, which sits beneath the brain – the commander-in-chief of the whole operation. The thyroid produces several hormones, including thyroxine, or T4. Most tissues throughout the body require thyroxine, as it helps regulate chemical reactions which determine how quickly our cells use energy. Too much, and metabolism becomes overactive; too little, and it slows down – sometimes significantly so. Brain, pituitary gland and thyroid all talk closely to one another, and listen – responding to each other’s call to keep thyroxine levels fine-tuned. It’s when this balanced communication breaks down that problems emerge – since the brain relies on thyroxine to function as well. That’s when symptoms affecting energy, metabolism, mood and thinking can start to give the game away. Too high, too low Thyroid disorders are good at mimicking other conditions: stress, depression, anxiety, poor sleep, or simply getting older – one reason they are sometimes missed. Broadly speaking, thyroid problems fall into two main categories. An underactive gland, producing too little thyroxine, causes hypothyroidism – and typically arises when the immune system damages the thyroid tissue. It might also arise after successful treatment for an overactive thyroid. It more commonly affects women, especially those over sixty. A slower metabolism can generate symptoms of tiredness, depression, and poor concentration. Weight gain, or difficulty losing weight are common, since the body is less effective at burning fuel. It can also trigger dry skin and hair, and cause constipation. The answer? You can replenish thyroxine by taking it as a tablet. Tweaking the dose is often needed, using repeat blood tests to check the circulating hormone levels. An overactive thyroid, or hyperthyroidism, is less common – but can also impact both body and mind. This is typically caused by an autoimmune illness called Graves’ disease, where the body inadvertently stimulates the thyroid gland to secrete too much thyroxine. It can also be caused by certain medications, or occasionally by consuming large amounts of iodine, which is essential to the production of thyroxine. There have been some rather striking case reports in which some patients have developed hyperthyroidism from eating large amounts of kelp and other seaweeds, which are iodine-rich. A faster metabolism burns fuel more quickly, so patients may notice they lose weight despite eating normally. But this isn’t a welcome trade-off, as hyperthyroidism can also cause an irregular or fast heartbeat, tremors, increased sweating, and psychological symptoms like anxiety, irritability and restlessness. In some cases, depression emerges too. Thyroid overactivity can be damaging to the body – but once diagnosed, can also be treated. This might include medications to reduce thyroxine levels, or the severity of symptoms, such as beta blockers. Radioactive iodine or surgery can also be used to reduce the amount of active thyroid tissue. Spotting the problem Slow-to-grow, mild or non-specific symptoms like these might not prompt a call to the doctor. Yet persistent changes in energy, mood, memory, concentration and weight are worth checking out. Diagnosis is often a simple blood test, leading to treatment just around a corner. There are physical clues too. Any lumps or masses in the neck, especially those that get bigger or don’t seem to go away, might be the sign of a thyroid problem. Some glands can enlarge massively, forming a swelling called a goitre, whilst other lumps can be caused by cancer – another reason as to why you should always get them checked out. Another place to look for hyperthyroidism is in the eyes – the high thyroxine levels of Graves’ disease can cause red, dry, swollen, even protruding eyes. This is a reason to see a doctor urgently, since this can threaten vision. At the extreme ends of the spectrum, both severe high and lows of thyroid function can be dangerous, though luckily these are rare occurrences. But what’s reassuring here is that treating either can improve many of the less visible symptoms – including anxiety, low mood, poor concentration and brain fog. Recovery, though, is not always instantaneous. Even after blood levels have returned to normal, it can take further changes in medication and time before patients to fully feel themselves again. Regardless, it’s worthwhile paying heed to that bow tie we all wear underneath the skin – not just because of its impact on weight and metabolism, but because of the surprisingly broad effect it can have on how you think, feel and function from day to day. Sometimes symptoms affecting mood and mind have another cause altogether, and deserve further investigation.