Chronic fatigue: possible causes, warning signs and natural solutions

Intense fatigue is n't just "being a little tired": when it becomes overwhelming , persistent , or prevents you from functioning normally , it warrants a structured approach. The goal isn't simply to "hang in there," but to identify the most likely cause, rule out urgent situations, and then implement a concrete plan (sleep, recovery, lifestyle changes, and, if necessary, a medical check-up). In this guide, you'll understand what to check, what to do starting today, and when to seek medical help.

Intense fatigue : what exactly are we talking about?

Fatigue, drowsiness, exhaustion: do not confuse them

• Fatigue / asthenia : lack of energy, difficulty with mental/physical effort, feeling of “empty battery”.
• Drowsiness : tendency to fall asleep (often linked to insufficient sleep or sleep apnea).
• Exhaustion : fatigue + feeling overwhelmed, sometimes associated with overwork/burnout.

The 3 criteria that should alert you

You need to be more vigilant if the intense fatigue is:

1. Persistent (≥ 2 weeks despite rest and adjustments).
2. Unexplained (no obvious cause).
3. Disabling (work, studies, driving, social life).

The most common causes of intense fatigue (and how to identify them)

1) Sleep debt and non-restorative sleep

Typical signs :

• unrefreshed awakenings, difficulty concentrating, irritability
• morning or afternoon slump
• need coffee to function

To be checked :

• actual sleep duration (over 7 days, not just one night)
• irregular hours, late-night screen time, alcohol in the evening

Key point : you can sleep “8 hours” but poorly, and remain exhausted.

2) Chronic stress, mental workload, overwork (leading to burnout)

Signs :

• Fatigue + rumination, internal tension, digestive problems
• Ineffective recovery even on weekends
• loss of pleasure, cynicism, decreased performance

Common mistake : compensating with more coffee, more “willpower”, fewer breaks → worsens the fatigue/stress cycle.

3) Insufficient nutrition, hydration, deficiencies

Clues :

• skipped meals, low protein intake
• Cravings, feelings of hypoglycemia, dizziness
• Heavy periods (possible iron deficiency)

4) Common medical causes to screen for (without self-diagnosis)

Certain medical conditions cause intense and persistent fatigue:

• anemia , infections (e.g., mononucleosis), hypothyroidism …
• diabetes or glycemic imbalance (depending on the context)
• side effects of medications (sedating antihistamines, certain anxiolytics, etc.)

Good reflex : note down when it started + what has changed (sleep, work, treatment, recent infection).

When to consult a doctor (and when is it urgent)?

Consult a doctor promptly if intense fatigue is associated with…

• unusual shortness of breath, chest pain, discomfort
• Persistent fever, unintentional weight loss
• palpitations, marked paleness, bleeding
• Intense sadness, dark thoughts, major disruption of daily life

Check if it persists despite simple measures

If rest, stress reduction, diet/hydration do not improve intense fatigue after about 2 weeks , a consultation is appropriate.

What assessment can be made when one is very tired?

What the doctor is looking for first

During a consultation for fatigue/asthenia, a doctor may prescribe a blood test aimed in particular at screening for anemia , infection (e.g. mononucleosis), hypothyroidism , etc.

How to prepare for the consultation (to get straight to the point)

Bring a mini “survey” (it improves the quality of the diagnosis):

• start date + possible trigger (infection, stress, change of routine)
• Sleep (hours, awakenings, snoring, drowsiness)
• Associated symptoms (pain, fever, weight loss, shortness of breath, mood)
• medications/supplements, alcohol, coffee, substances
• menstrual cycle (if applicable) + heavy periods

What to do right now: a 7-day action plan (pragmatic)

Step 1: Ensure safe sleep (priority #1)

1. Fixed wake-up time (± 30 min), even on weekends
2. Natural light in the morning 10–20 min
3. Stop screens and intense cognitive work 60–90 minutes before bedtime
4. Coffee: ideally not after 2–3 pm (adjust according to sensitivity)

Step 2: Stabilize the energy (without “peaks”)

• breakfast or first protein
• eat regular meals, avoid isolated "all-sugar" diets
• Fractionated hydration (often underestimated)

Step 3: Move… but intelligently

• If exhaustion occurs: aim for 10–20 minutes of gentle walking daily
• Avoid a sudden return to sports "to get back in shape" (often counterproductive)

Step 4: Reduce mental workload in a measurable way

• 1 list “urgent today” (max 3 items)
• 1 non-negotiable 10-minute break block x 2/day
• Delegate/remove 1 task this week (concrete objective)

Step 5: Measure to decide (instead of assuming)

For 7 days, note:

• Fatigue 0–10 morning/afternoon
• sleep duration
• caffeine (amount/hour)
• physical activity
• major stressful event

If there is no clear improvement → consultation + assessment.

Common mistakes that perpetuate intense fatigue

• Increasing the intake of stimulants (coffee/energy drinks) instead of addressing recovery
• “Relaxing” by scrolling late at night (perceived rest ≠ physiological rest)
• Forcing intense exercise when the body is signaling a limit
• Self-prescribing iron/supplements “at random” without assessment (risk of error, masking of the diagnosis)

FAQ 

Can intense fatigue be

Yes. Chronic stress can cause intense fatigue through hyperactivity (disturbed sleep, insufficient recovery) and high mental workload, often with irritability and concentration problems.

When should I consult a doctor for extreme fatigue ?

If fatigue is persistent, unexplained, debilitating, or if it does not improve after about two weeks of simple measures (rest, stress reduction, lifestyle), you should consult a doctor.

What blood test results are needed when you are constantly tired?

The doctor may request tests to look for conditions such as anemia , infection (e.g., mononucleosis), or a thyroid disorder like hypothyroidism .

Is intense fatigue necessarily

No, it is often linked to sleep, stress, or lifestyle habits. But it becomes an important signal if it persists, worsens, or is accompanied by warning signs.

What should you do immediately when you have no energy left?

Prioritize sleep (regular schedule), reduce late-night stimulants, eat more regularly (including protein), take a gentle walk every day, and monitor your progress over 7 days. If there is no improvement, consult a doctor.

Conclusion

Severe fatigue is effectively treated by combining: (1) triage of warning signs, (2) a simple plan focusing on sleep, recovery, and energy, and (3) a medical evaluation if fatigue persists or becomes debilitating. Implement the 7-day plan, monitor your indicators, and if there is no significant improvement, schedule an appointment for a proper investigation (without self-diagnosis).