Fatigue brings more people through my door than almost anything else. It cuts across every age group, every walk of life, and yet it remains one of the most poorly understood symptoms in general practice. Most patients arrive having already formed a theory about what’s wrong. Some have spent hours searching online. Others have been quietly worried for months but talked themselves out of coming in. So this month I want to address some of the things I hear most often, because a lot of what people believe about tiredness simply isn’t true — and some of the real causes are ones that rarely get mentioned atall.
“I must be anaemic or have a thyroid problem.”
This is where most people start, and understandably so. Iron deficiency and thyroid dysfunction are well known causes of fatigue, and they’re among the first things I check. But they account for far fewer cases than people expect. When blood tests come back normal, patients often feel like they’re back to square one, or worse, that they’re not being taken seriously. Neither is true. Normal results are genuinely useful. They tell us we need to look somewhere else, and in most cases that somewhere else turns out to be sleep, chronic stress, workload, or the cumulative weight of what someone is carrying in their life. Those things are real, they are treatable, and they are absolutely worth talking about.
“I just need more sleep.”
Hours in bed and actual rest are not the same thing. You can spend eight or nine hours asleep and still wake up feeling completely depleted if that sleep is fragmented or unrefreshing. Conditions like sleep apnoea interfere with the quality of sleep throughout the night, and many people have no idea they have it. It is far more common than most people realise and is regularly missed, particularly in women and in people who aren’t obviously overweight. If you wake most mornings feeling like you haven’t slept at all, or your partner has mentioned that you snore heavily or stop breathing during the night, please bring it up. It’s one of the more straightforward things to investigate and the difference treatment makes can be significant.
“It’s just my age.”
I hear this constantly, and I’d gently push back on it every time.Yes, sleep patterns change as we get older and recovery takes longer than it once did. But persistent, limiting fatigue is not something you should simply accept as the price of getting older. That kind of thinking is one of the main reasons people wait far too long before asking for help.
“If something was really wrong, I’d have other symptoms.”
Not necessarily. Fatigue can be the primary or only noticeable feature of a number of conditions including coeliac disease, depression, earlydiabetes, and certain inflammatory conditions. The details of how tiredness presents matter enormously — how long it has been going on, whether it’s there every day or comes and goes, what time of day it’s worst, whether anything relieves it. A careful conversation about these things often tells me more than any blood test.
“I’m just stressed. It’ll pass.”
Stress is genuinely exhausting, and people are often right thatit’s a contributing factor. The problem is that chronic stress doesn’t tend to just pass on its own. When the body is running on adrenaline for weeks or months at a stretch, fatigue becomes the new baseline. People adapt to feelingworn down and stop noticing how far from normal they’ve drifted. By the time someone comes to see me, they’ve often been running on empty for far longer than they realise. Stress related fatigue deserves proper attention, not just reassurance that things will settle down eventually.
“I eat well and exercise, so it can’t be lifestyle.”
Healthy habits are genuinely protective, but they don’t make anyone immune. Fatigue in otherwise healthy, active people is common and oftencomes down to things that don’t show up on a food diary. Alcohol is one worth mentioning honestly. Even moderate, regular drinking disrupts sleep architecture in ways most people don’t notice until they stop. Overtraining is another — exercise is restorative up to a point, but pushing hard without adequate recovery quietly depletes rather than builds. And for many people, particularly those juggling demanding careers and family life, the issue isn’twhat they’re doing but the sheer relentlessness of it with no real downtime built in.
“It’s probably just depression.”
Sometimes it is, and depression is one of the most undertreated causes of fatigue I see. But self diagnosing and then dismissing the issue aspurely psychological can mean missing something physical, just as assuming it must be physical can mean missing the mental health piece entirely. The two are also not mutually exclusive — chronic illness causes low mood, and persistent low mood causes physical exhaustion. A good assessment considers both, without hierarchy.
“There’s nothing that can really be done about it.”
This is perhaps the belief that concerns me most, because it keeps people from seeking help at all. The reality is that most causes of fatigue, once properly identified, are very manageable. Sleep disorders respond well to treatment. Nutritional deficiencies are correctable. Mental health conditions have effective therapies. Lifestyle factors can be addressed with support rather than willpower alone. Even conditions like chronic fatigue syndrome, which are more complex, benefit significantly from the right medical guidance and a structured approach.
The point I want to make is a simple one. If tiredness is affecting your work, your relationships, your mood, or your ability to enjoy your life, that is enough of a reason to come in. You do not need to wait until things deteriorate further or until you can point to something more dramatic. Fatigue is a symptom and symptoms deserve proper assessment. Book a longer appointment and we’ll work through it properly together.
Dr Simon Kerr
