4 min read · Oct 24, 2026
Why Am I Always Tired? Causes of Fatigue and Brain Fog
Tiredness that does not go away with sleep rarely has a single cause. Here is what may be behind it and what a proper assessment looks at.
Feeling tired now and then is normal. Feeling tired all the time, even after a full night in bed, is different. It is one of the most common reasons people see a doctor, and it rarely has just one cause.
Fatigue is a symptom, not a diagnosis
Persistent tiredness and brain fog are signals that something may need attention. Often several things contribute at once, which is why a quick fix rarely works. Common contributors include:
- Poor sleep or sleep apnoea
- Anaemia or low iron
- Thyroid disease
- Low vitamin D or B12
- Perimenopause or other hormonal changes
- Low mood or depression
- Some medicines
- Long-term stress or a recent infection
What a proper assessment looks like
Before building a plan, a good assessment starts with the whole picture, not a single test. It usually covers:
- Your health history and when the tiredness began
- Sleep and mood screening
- A physical examination
- Selected tests, such as a full blood count, ferritin, thyroid function, vitamin D, B12 and blood sugar
Tests are chosen because the result will change your care, not because more testing feels more thorough.
Why supplements are not the first step
Supplements help when there is a reason to take them, such as a confirmed deficiency. Taking them without knowing the cause can waste money and hide the real problem. It is best to discuss them with a clinician first.
When to get checked
Book a consultation if tiredness has lasted more than a few weeks, is affecting work or relationships, or comes with other changes such as low mood, poor sleep, hair or skin changes, or unexplained weight change.
Sudden confusion, a sudden change in thinking, chest pain or fainting need urgent medical attention, not an appointment. Go to the nearest emergency department.
If you want to know what might be behind your tiredness, you can read about the fatigue and brain fog consultation with Dr Fouzia in Dubai.
This article is educational and does not replace advice from a qualified clinician.
Consultant family physician in Dubai who practises functional medicine, Calm Mind Sessions and aesthetic medicine. She l…
FAQs
Why am I always tired?
There are many possible causes, and often several contribute at once. A medical assessment can help identify what may be affecting your energy.
Which blood tests can check for fatigue?
Depending on your symptoms and history, a clinician may consider a full blood count, ferritin, thyroid function, vitamin D, B12 and blood sugar.
Is brain fog serious?
Brain fog is a symptom rather than a diagnosis and has many possible causes. Sudden confusion or a sudden change in thinking needs urgent medical attention.
Will supplements fix my fatigue?
Supplements are useful when there is a reason to take them, such as a confirmed deficiency. They do not address every cause of fatigue, so it is best to discuss them with a clinician.