Why Am I Always Tired? Common Causes of Fatigue and When to See a Doctor

Feeling tired after a busy week, a poor night’s sleep or a period of unusual stress is normal. However, tiredness that continues for weeks, returns frequently or begins affecting your concentration, work, relationships and everyday activities may deserve a closer medical assessment.

Persistent fatigue is not a diagnosis on its own. It is a symptom with many possible causes, ranging from insufficient sleep and emotional stress to iron deficiency, thyroid problems, diabetes, medication effects and other underlying health conditions.

Hout Bay Family Medical Clinic provides comprehensive assessment for patients experiencing ongoing tiredness, low energy, weakness or reduced stamina. A family doctor can help identify likely causes, arrange appropriate blood tests and develop a personalised treatment plan.

What Is Fatigue?

Fatigue is more than simply feeling sleepy. It may be experienced as physical exhaustion, mental tiredness, reduced motivation, poor concentration or a persistent lack of energy.

Some people describe fatigue as:

• Waking up feeling unrefreshed;
• Struggling to complete normal daily tasks;
• Needing significantly more rest than usual;
• Feeling physically weak or heavy;
• Having difficulty concentrating;
• Losing motivation;
• Becoming exhausted after relatively minor activity; or
• Feeling tired even after apparently adequate sleep.

Fatigue that is not relieved by rest may indicate an underlying medical, sleep-related or psychological concern that requires assessment.

1. Poor Sleep and Insomnia

One of the most common causes of tiredness is simply not getting enough good-quality sleep. This may result from late nights, shift work, caring for a baby, stress, pain or an inconsistent sleep routine.

Insomnia can involve:

• Difficulty falling asleep;
• Waking repeatedly during the night;
• Waking earlier than intended;
• Feeling unable to switch off mentally; or
• Sleeping for several hours but still feeling unrefreshed.

Regular alcohol use, excessive caffeine, evening screen time and certain medications can also interfere with sleep quality.

A doctor can help assess whether fatigue is primarily related to sleep habits or whether another condition is disrupting normal sleep.

2. Sleep Apnoea

Obstructive sleep apnoea causes breathing to repeatedly stop or become restricted during sleep. These interruptions can prevent restorative sleep even when a person appears to spend enough hours in bed.

Possible signs include:

• Loud snoring;
• Gasping or choking during sleep;
• Morning headaches;
• A dry mouth on waking;
• Poor concentration;
• Irritability;
• Excessive daytime sleepiness; and
• Persistent tiredness despite a full night’s sleep.

A partner may notice the breathing interruptions before the patient does. Sleep apnoea is one of several sleep disorders that can cause significant fatigue and may require specialist investigation.

3. Stress and Burnout

Long-term stress can leave the body and mind feeling depleted. Work pressure, financial concerns, relationship difficulties, parenting demands and caring for relatives may all contribute to emotional and physical exhaustion.

Burnout may cause:

• Persistent tiredness;
• Irritability;
• Reduced motivation;
• Poor concentration;
• Headaches or muscle tension;
• Sleep difficulties;
• Feeling emotionally detached; and
• Reduced performance at work or home.

Although rest can help, ongoing burnout may require broader support, including changes to workload, sleep, boundaries, exercise and mental-health care.

4. Depression and Anxiety

Depression does not always present as obvious sadness. Some people primarily experience low energy, reduced motivation, poor concentration, disrupted sleep or a loss of interest in activities.

Anxiety can also be exhausting. Constant worry, physical tension, racing thoughts and poor sleep can leave a person feeling depleted throughout the day.

The World Health Organization lists fatigue, low energy, sleep disturbance and concentration difficulties among common symptoms of depression.

Speak to a doctor when tiredness is accompanied by persistent low mood, hopelessness, loss of enjoyment, panic, withdrawal or difficulty coping.

5. Iron Deficiency and Anaemia

Iron is required for the production of haemoglobin, which helps red blood cells carry oxygen throughout the body. Low iron levels may cause fatigue even before significant anaemia develops.

Possible symptoms include:

• Tiredness and weakness;
• Shortness of breath;
• Headaches;
• Dizziness;
• Pale skin;
• Heart palpitations;
• Poor concentration;
• Restless legs; and
• Reduced exercise tolerance.

Iron deficiency may be related to heavy menstrual bleeding, pregnancy, dietary intake, digestive conditions, blood loss or difficulty absorbing iron.

A doctor may recommend a full blood count and iron studies rather than assuming that an iron supplement is needed. Fatigue is associated with both iron deficiency and iron-deficiency anaemia.

6. Vitamin B12 or Folate Deficiency

Vitamin B12 and folate support healthy red-blood-cell production and normal nervous-system function. Deficiency may contribute to fatigue, weakness, poor concentration and neurological symptoms.

Possible additional symptoms include:

• Pins and needles;
• Numbness;
• Balance difficulties;
• A painful tongue;
• Memory concerns;
• Mood changes; and
• Pale or yellowish skin.

People following restrictive diets, those with absorption disorders and patients taking certain medications may have an increased risk.

Blood testing can help determine whether supplementation or vitamin B12 injections are clinically appropriate.

7. Thyroid Disorders

The thyroid gland helps regulate metabolism, energy and many other body processes. Both an underactive and overactive thyroid can cause fatigue.

An underactive thyroid may also cause:

• Weight gain;
• Feeling unusually cold;
• Dry skin;
• Constipation;
• Muscle aches;
• Hair changes;
• Heavy periods;
• Low mood; and
• Slower thinking.

An overactive thyroid may cause tiredness alongside:

• Weight loss;
• Palpitations;
• Tremor;
• Heat intolerance;
• Anxiety;
• Sweating; and
• Difficulty sleeping.

Thyroid conditions are among the recognised medical causes of fatigue and can usually be investigated through blood tests.

8. Diabetes and Blood-Sugar Problems

Fatigue can occur when the body is not managing blood sugar effectively. Some people with Type 2 diabetes or pre-diabetes have few obvious symptoms.

Possible signs include:

• Increased thirst;
• Frequent urination;
• Blurred vision;
• Slow-healing wounds;
• Recurring infections;
• Unexplained weight changes; and
• Persistent tiredness.

A fasting glucose or HbA1c blood test may be recommended based on symptoms and risk factors such as family history, high blood pressure, excess weight or previous gestational diabetes.

9. Hormonal Changes

Hormonal changes during puberty, pregnancy, the postnatal period, perimenopause and menopause can all affect energy and sleep.

Women experiencing fatigue may also notice:

• Changes in menstrual cycles;
• Heavy bleeding;
• Hot flushes;
• Night sweats;
• Sleep disturbance;
• Mood changes;
• Reduced concentration; or
• Changes in weight.

Heavy periods can also contribute to iron deficiency, so fatigue should not automatically be attributed to hormones alone.

10. Infection and Post-Viral Fatigue

Fatigue is common during and after viral infections. Colds, influenza, glandular fever and COVID-19 can all leave patients feeling tired while the body recovers.

Post-viral fatigue may persist after other symptoms have settled. Recovery should generally be gradual, with attention to rest, hydration, nutrition and a careful return to activity.

Arrange an assessment when fatigue continues without improvement, is unusually severe or is accompanied by recurring fever, swollen glands, weight loss, coughing or other persistent symptoms.

11. Medication Side Effects

A wide range of medicines can contribute to tiredness or daytime sleepiness. These may include some:

• Antihistamines;
• Antidepressants;
• Anxiety medicines;
• Strong pain medication;
• Blood-pressure medicines;
• Sleeping tablets;
• Anti-nausea medicines; and
• Other sedating treatments.

Do not stop prescribed medication without medical advice. Your doctor can review the timing, dosage and possible alternatives where medication may be contributing to fatigue.

12. Alcohol and Substance Use

Alcohol may initially make a person feel sleepy but can disrupt normal sleep quality and contribute to fatigue the following day. Regular or heavy alcohol use can also affect mood, liver health, nutrition and energy.

Recreational substances and excessive caffeine may similarly interfere with sleep and daytime functioning.

A confidential discussion with your doctor can help identify whether alcohol, medication or another substance is affecting your energy.

13. Poor Nutrition and Dehydration

Skipping meals, restrictive diets and inadequate fluid intake may contribute to weakness and reduced energy.

Fatigue may occur when a person is not receiving enough:

• Calories;
• Protein;
• Iron;
• Vitamin B12;
• Folate;
• Other essential nutrients; or
• Fluids.

However, persistent fatigue should not automatically be treated with supplements. Unnecessary vitamins may not help when the underlying cause is sleep, depression, thyroid disease, diabetes or another condition.

14. Chronic Pain and Long-Term Medical Conditions

Living with ongoing pain can be physically and emotionally exhausting. Arthritis, fibromyalgia, migraines and persistent back or joint pain may all disrupt sleep and reduce activity.

Fatigue can also occur with chronic conditions affecting the heart, lungs, kidneys, liver or immune system. Persistent pain and certain chronic illnesses are recognised causes of fatigue.

Effective treatment should address both the underlying condition and the effect fatigue has on daily life.

15. ME/CFS and Other Persistent Fatigue Conditions

Myalgic encephalomyelitis, also known as chronic fatigue syndrome or ME/CFS, is a long-term illness associated with severe fatigue, unrefreshing sleep, cognitive difficulties and worsening symptoms after physical or mental activity.

The fatigue experienced with ME/CFS is not relieved by ordinary rest and may significantly limit everyday activities.

ME/CFS should not be self-diagnosed. Other possible medical causes need to be assessed first, and diagnosis should be based on recognised clinical criteria.

When Should You See a Doctor About Fatigue?

Arrange a medical appointment when tiredness:

• Has continued for several weeks;
• Is becoming progressively worse;
• Is not explained by an obvious temporary cause;
• Is not relieved by adequate sleep;
• Affects work, exercise, relationships or daily tasks;
• Is accompanied by weakness or breathlessness;
• Occurs with unexplained weight loss;
• Is associated with heavy menstrual bleeding;
• Develops alongside mood or concentration changes;
• Follows an illness and is not improving; or
• Causes concern even if you cannot identify another symptom.

Persistent fatigue deserves assessment rather than repeated self-treatment with vitamins, stimulants or energy drinks.

Warning Signs Requiring Prompt Medical Attention

Seek urgent medical care when fatigue occurs with:

• Chest pain;
• Significant breathing difficulty;
• Fainting;
• New confusion;
• Severe weakness;
• Black or bloody stools;
• Vomiting blood;
• Uncontrolled bleeding;
• A rapid or irregular heartbeat;
• Sudden neurological symptoms;
• Severe dehydration;
• Suicidal thoughts; or
• A sudden and significant deterioration.

These symptoms require prompt assessment and should not be submitted through a routine website enquiry.

What Will Your Doctor Ask?

A fatigue consultation may include questions about:

• When the tiredness started;
• Whether it is constant or fluctuates;
• Sleep duration and quality;
• Snoring or possible sleep apnoea;
• Work and family pressures;
• Mood, anxiety and stress;
• Menstrual or hormonal changes;
• Diet and weight changes;
• Alcohol and caffeine use;
• Medication and supplements;
• Recent illnesses;
• Pain or other symptoms; and
• Personal and family medical history.

Clinical guidance recommends assessing the onset, severity, frequency, duration and pattern of fatigue, together with possible triggers and associated symptoms.

Which Tests May Be Recommended?

Not every patient needs the same investigations. Testing should be guided by symptoms, examination findings and individual risk.

Possible investigations may include:

• A full blood count;
• Iron and ferritin levels;
• Vitamin B12 or folate;
• Thyroid-function testing;
• Blood-glucose or HbA1c testing;
• Kidney and liver-function tests;
• Inflammatory markers;
• Urine testing;
• Pregnancy testing where relevant; or
• Other targeted investigations.

Your doctor may also recommend sleep assessment, mental-health support, an ECG or specialist referral depending on the clinical findings.

Practical Ways to Support Your Energy

While awaiting assessment—or when lifestyle factors are contributing—the following may help:

• Maintain consistent sleep and waking times;
• Reduce caffeine later in the day;
• Limit alcohol;
• Eat regular, balanced meals;
• Drink sufficient water;
• Introduce gentle physical activity gradually;
• Take regular breaks during demanding days;
• Address ongoing stress;
• Avoid relying on energy drinks; and
• Keep a brief record of symptoms, sleep and activity.

Lifestyle changes can be helpful, but they should not delay medical assessment when fatigue is persistent or accompanied by concerning symptoms.

Fatigue Assessment in Hout Bay

Hout Bay Family Medical Clinic provides personalised medical assessment for patients experiencing persistent fatigue, weakness, poor concentration or reduced energy.

Care may include:

• A full medical consultation;
• Review of sleep, stress and lifestyle factors;
• Assessment for depression, anxiety and burnout;
• Medication review;
• Blood-pressure and cardiovascular assessment;
• Laboratory investigations;
• Testing for anaemia, iron deficiency, diabetes or thyroid disorders;
• Vitamin B12 assessment and treatment where appropriate;
• Management of identified medical conditions; and
• Specialist referral when required.

Fatigue is common, but feeling constantly exhausted should not simply be accepted as part of a busy life.

Contact Hout Bay Family Medical Clinic to arrange an appointment if persistent tiredness is affecting your health, work or quality of life.