Constant tiredness: common causes and what to do

The most frequent causes are ordinary and they add up: sleeping badly or too little, prolonged stress, an unbalanced diet, not drinking enough, too little physical activity and too much screen time at night. The UK's National Health Service (NHS) describes occasional tiredness as normal and lists, among the usual reasons, lack of sleep, stress, hormonal changes such as puberty, pregnancy or the menopause, some illnesses such as glandular fever and COVID-19, and also certain treatments and medicines.

Is constant tiredness normal, or should I be worried?

Both things can be true at once. What changes the picture is how long it has lasted and how much it is affecting you.

NHS guidance is clear: if you have been tired for a few weeks without knowing why, or if the tiredness is affecting your daily life — work, study, relationships, things you used to enjoy — you should speak to a doctor. Not because there is necessarily something serious going on, but because the assessment exists precisely to tell everyday tiredness apart from something that needs attention. At an appointment, a doctor may ask for blood tests to check for things such as anaemia, diabetes or an overactive thyroid.

Notice what the guidance does not say: it does not say you should wait months, nor that you should first exhaust every lifestyle change before seeking help. If tiredness is clouding your days, that is reason enough to book an appointment.

The everyday causes, from the most common to the less obvious

It is worth going through these in order, because the most likely one is almost always the most boring to fix.

Too little sleep, or sleep at the wrong times

If you work shifts, have small children or always go to bed at whatever time your phone decides, start here.

Prolonged stress

Stress uses up a lot of energy. That is not a motivational metaphor — public health information on tiredness itself links stress to a real energy cost.

Food and drink

An unbalanced diet and not drinking enough water are on the list of factors that public health information links to tiredness. Sometimes tiredness is simply mild dehydration — drinking little through the day, especially with coffee standing in for water.

Too little physical activity

It sounds counterintuitive: you are tired, so you rest. But regular exercise is part of the recommendations for coping with tiredness, and public health information notes that even a single 15-minute walk can give an energy boost.

Screens and the run-up to bedtime

The recommendation is to avoid phones and screens in the hour before sleep and to set aside a couple of hours to wind down before bedtime.

Hormonal changes and illness

Puberty, pregnancy and the menopause appear among the listed causes, as do some illnesses — glandular fever, COVID-19 — and certain medicines and treatments. At this point it is no longer a question of routine, and it is the kind of cause that gets clarified with a professional, not by trial and error.

What you can change this week

Concrete steps, with amounts and times, so this does not stay a good intention.

1. Fixed sleep hours. Pick a bedtime and a waking time and stick to them for seven days, including the weekend. Regularity is the part most people miss.
2. One hour without screens before bed. If an hour is unrealistic, start with thirty minutes. Leave your phone outside the bedroom or far from the bed.
3. Two hours of winding down before bedtime. Lower lights, calm tasks, no sorting out loose ends at eleven at night.
4. A 15-minute walk. Every day, if you can. Public health information indicates that a short walk can give an energy boost — and it is one of the cheapest measures there is.
5. Water through the day. Do not wait until you are thirsty. Keep a bottle in sight and drink before your coffee.
6. Regular meals.

Do this for two to three weeks before deciding it does not work.

What usually does not help

There is a lot of popular advice about tiredness that does not match what is known. A few examples:

• More coffee to compensate.
• Energy supplements as a first step. No supplement replaces sleep, food and movement. Treating them as a starting point is beginning at the end.
• Total rest. The recommendation is regular exercise, not complete bed rest.
• Self-diagnosis online. The guidance is explicitly not to diagnose yourself. A list of causes is not a diagnosis, and the anxiety of hunting for symptoms rarely helps.

There is also a temptation to pin everything on one thing — "it's low iron", "it's my thyroid", "it's stress".

Where supplements honestly fit

Here the answer is modest, and it is worth saying so before any product name.

Energy Gummies with Guarana combine, per two-gummy serving, guarana extract (200 mg, of which 44 mg caffeine), L-theanine (200 mg), L-tyrosine (100 mg), vitamin B6, vitamin B12 and vitamin C. They contain caffeine, and that matters: they are not recommended for children, pregnant or breastfeeding women, and they should be chewed preferably after a meal, without exceeding the daily dose.

Multivitamin Gummies include B-complex vitamins, vitamin C, vitamin D, vitamin E, zinc and folic acid, among others. Covering a gap is not the same as gaining extra energy if your diet is already good.

Before buying any supplement, check the label and speak to a pharmacist, especially if you take medicines or have a health condition. And keep your expectations realistic: if the tiredness comes from sleeping five hours a night, no gummy will fix that.

Signs that mean you should see a doctor

See a doctor if the tiredness has lasted a few weeks without an identifiable reason, if it is interfering with your daily life, or if it comes with something that worries you. At an appointment, a doctor may ask for tests to rule out anaemia, diabetes or an overactive thyroid.

Do not try to work out the cause on your own before you go. Go with what you know: how long it has been going on, what has changed, how you sleep, what you eat, what medicines you take. That is more useful than a list of suspicions.

How long until you know it is working

It is not possible to promise a timeline, because it depends on the cause and on the person. Give the measures in this article two to three weeks before assessing them, and keep a simple record — bedtime, hours slept, whether you walked, how much water you drank. A notebook or a note on your phone is enough.

If, after a few weeks of consistent routine, you still have no energy and no explanation, that is the most valuable information you can take to an appointment. It is not a failure on your part, and it is not a reason to buy more supplements. It is a sign that it is worth investigating with someone who has the tools for it.