What Causes Chronic Fatigue in Teenagers?
- New Pathways Programme
- Jun 2
- 4 min read
Updated: Aug 25
7 Key Reasons Your Teen May Be Constantly Tired
If you’ve been asking yourself, “What causes chronic fatigue in teenagers?” — you’re not alone. Many parents find themselves worrying when their previously energetic teen becomes unusually tired, withdrawn, or unable to keep up with everyday activities.
Fatigue in teens can be more than just a need for a few early nights. When tiredness becomes chronic—lasting weeks or months and interfering with school, social life, or emotional health—it’s a sign that something deeper may be going on.
In this article, we’ll explore seven of the most common causes of chronic fatigue in teenagers, how to spot the signs, and what you can do to help.
1. Poor Sleep Hygiene and Irregular Routines
Teenagers are biologically wired to go to bed later and sleep longer - but school schedules, social media, and screen use can wreak havoc on their natural rhythms. Chronic sleep deprivation can quickly lead to burnout, brain fog, and physical exhaustion.
Signs:
Difficulty waking up in the morning
Sleeping in excessively on weekends
Always feeling groggy, even after 8+ hours of sleep
Tip: Encourage a regular wind-down routine, reduce screen exposure before bed, and aim for at least 8–10 hours of sleep per night.
2. Nutritional Deficiencies
Teenagers often skip meals or rely on fast food and energy drinks, which can lead to deficiencies in iron, B12, vitamin D, or magnesium. These nutrients are essential for energy production, and deficiencies can cause persistent fatigue, poor concentration, and low mood.
Signs:
Pale skin
Frequent headaches or dizziness
Low motivation or poor focus
What to Do: Speak to a healthcare provider about checking blood levels, and introduce energy-supporting foods like leafy greens, lean proteins, nuts, and fortified cereals.
3. Stress, Anxiety, and Emotional Burnout
Academic pressure, social anxiety, low self-esteem, and family conflict can all contribute to emotional overload. Stress depletes the body’s energy reserves and affects sleep, immunity, and hormone balance—making it one of the most overlooked causes of chronic fatigue in teenagers.
Symptoms of emotional fatigue:
Mood swings or irritability
Withdrawal from friends or hobbies
Trouble sleeping or constant worry
If your teen’s fatigue seems to coincide with emotional stress, it could be a psychological cause rather than physical.
4. Over-commitment and Lack of Rest
Today’s teens are often overloaded with school, homework, sports, extracurriculars, part-time jobs, and online social lives. This “always on” lifestyle leaves little time for genuine rest and recovery.
Burnout isn’t just for adults - teenagers need unstructured downtime to recharge both physically and mentally.
Watch for:
A constant sense of being overwhelmed
Drop in academic performance
Complaints of feeling “tired all the time” despite being busy
Remember, chronic fatigue in teenagers can sometimes be a symptom of doing too much, not too little.
5. Undiagnosed Medical Conditions
If your teen is persistently tired with no clear cause, an underlying medical condition may be involved. Conditions linked to teenage fatigue include:
Chronic Fatigue Syndrome (CFS/ME)
Long COVID
Thyroid imbalances (hypothyroidism)
Anaemia
Type 1 diabetes
Sleep disorders (e.g. sleep apnoea)
When to see a doctor:
Fatigue lasting longer than 3 months
Symptoms worsen after activity or exercise
Associated symptoms like pain, dizziness, or brain fog
A proper diagnosis is key to targeted treatment and support.
6. Post-Viral Fatigue and Long COVID
Viral infections like glandular fever (Epstein-Barr) or COVID-19 can disrupt the immune and nervous systems, leading to prolonged fatigue, memory problems, and energy crashes after exertion. In some teens, this develops into post-viral fatigue syndrome or Long COVID.
This type of fatigue may:
Fluctuate daily
Worsen with mental or physical effort
Be mistaken for laziness or depression
If you’re wondering what causes chronic fatigue in teenagers following illness, post-viral effects are increasingly common—and deserve professional attention.
7. Hormonal Changes and Growth Spurts
Puberty is a time of massive biological change. Shifts in hormone levels, growth demands, and body clock adjustments can all lead to unexplained tiredness. While this is often temporary, it can worsen other fatigue-related conditions if left unmanaged.
Signs it’s hormonal:
Growth spurts
Mood swings
Changes in appetite and sleep needs
Healthy habits and reassurance are often enough, but keep an eye on whether symptoms escalate or persist.
🔍 What to Do If You’re Wondering What Causes Chronic Fatigue in Teenagers
If your teenager’s fatigue is:
Lasting more than 4 weeks
Affecting school, friendships, or confidence
Getting worse with activity instead of better with rest
Accompanied by pain, dizziness, or brain fog
…it’s time to seek professional support.
Chronic fatigue in teenagers isn’t “just a phase.” Getting help early can make a real difference in recovery and prevent issues from becoming long-term.
🌿 How the New Pathways Programme Can Help
At the New Pathways Programme, we specialise in helping teenagers recover from chronic fatigue, Long COVID, and post-viral fatigue syndromes. Our holistic, science-backed approach focuses on:
Nervous system regulation
Restorative routines
Energy pacing and recovery
Emotional resilience
We understand what causes chronic fatigue in teenagers—and more importantly, what helps them get their lives back.
👇 Worried About Your Teen’s Fatigue?
Book a Free Consultation Today » Let’s explore how we can support your family—because no parent should have to navigate this alone.
