Skip to content
AlternativeMed
Understand and address persistent tiredness: a bedside table in soft morning light with a glass of water, a paper notebook and pencil, and a small bowl of dried apricots and almonds beside a rumpled white sheet

Energy & Vitality

Why Am I So Tired? Fatigue, Sleepiness, Weakness and Low Motivation

Being tired now and then is normal, but tiredness that lasts for weeks, or that you cannot explain, deserves a proper look rather than another coffee. This page helps you describe what kind of tiredness you have, shows the common everyday and medical reasons for it, and explains when to get checked. It cannot tell you why you are tired, and nothing here is a diagnosis.

General information, not medical advice. Last updated October 31, 2026. Written by the AlternativeMed editorial team. Not medically reviewed.

Start here

  • If you have felt tired for a few weeks and are not sure why, book a visit with a doctor or nurse. Do not wait it out, and do not guess with iron, B12 or other pills first.
  • Keep a simple tiredness diary for one to two weeks (when you feel most and least tired, sleep, meals, medicines, mood) and bring it with you.
  • Meanwhile protect the basics: regular sleep times, regular meals, water through the day, some gentle movement if it does not leave you worse afterward, and less alcohol.

Be careful with

  • Tiredness has many possible causes, from sleep and stress to anemia, thyroid problems, medicines, low mood, sleep apnea and other illnesses. A list of symptoms cannot tell them apart; tests and a clinician can.
  • Caffeine and other stimulants are not an effective treatment for fatigue and can make it worse when they wear off.
  • Do not stop or change a prescribed medicine because you think it is making you tired. Ask the prescriber first.
  • If effort makes you feel worse hours or days later, say so plainly to your clinician and read about post-exertional malaise before pushing yourself to do more.

Get help when

  • Tiredness that has lasted a few weeks without a clear reason, affects your daily life, or comes with other symptoms such as weight loss or mood changes.
  • Loud snoring, gasping, snorting or choking noises in sleep, or always feeling very sleepy in the day.
  • Confusion or dizziness, blurred vision, little or no urine, or recent swelling and weight gain: contact a provider right away.
  • Unusual tiredness with dizziness that does not go away, dark urine or passing very little urine: ask for an urgent appointment (in the UK, NHS 111). Difficulty breathing, confusion, cold or pale skin, or being very hard to wake needs an emergency number.
  • Feeling worse for a day or more after physical or mental effort, or fatigue that started after an infection and has not settled.
  • Low mood, hopelessness or thoughts of harming yourself. In the US you can call or text 988 (free, 24/7); elsewhere use your local emergency number.

About Why Am I So Tired? Fatigue, Sleepiness, Weakness and Low Motivation

What this goal means

This goal is about understanding lasting tiredness: working out what kind of tiredness you have, looking at the usual everyday causes, and getting the right medical checks when it does not settle. It is different from a one-off tired day, and different from building day-to-day energy, which has its own page.

Fatigue is a symptom, not a disease. MedlinePlus describes it as a lack of energy and motivation, and sleepiness (drowsiness) as the need to sleep. The two can occur together.

1,2

Tired is not one single feeling

People use the word tired for several different experiences, and telling them apart helps you describe what is happening and helps a clinician decide where to look: fatigue (lack of energy), sleepiness (needing to sleep), weakness (muscles that feel weaker than usual), low motivation (little drive or interest), reduced endurance (getting breathless or worn out sooner than before) and feeling worse after effort.

The NHS notes that muscle weakness can appear with tiredness in some conditions, such as an overactive thyroid, and that shortness of breath can appear alongside lack of energy in iron deficiency anemia. Low motivation can be part of fatigue and is also listed among the symptoms of depression. Feeling worse after physical or mental activity, sometimes hours or days later, is called post-exertional malaise.

1,3,4,5

Common everyday contributors

The NHS lists these common causes of tiredness and fatigue: not enough sleep or trouble getting to sleep; an unhealthy lifestyle, such as an unhealthy diet and little exercise; stress, depression and life challenges such as bereavement or caring for a new baby; hormonal changes such as puberty, pregnancy or the menopause; some illnesses such as glandular fever and COVID-19; and some medical treatments and medicines.

MedlinePlus adds that fatigue can be a normal response to physical activity, emotional stress, boredom or lack of sleep, and lists drinking too much alcohol, too much caffeine that spoils sleep, and too little or too much exercise as lifestyle contributors.

3,2

Medical contexts a clinician may look at

When tiredness goes on without a clear reason, clinicians consider medical causes. MedlinePlus lists many, including anemia, iron deficiency without anemia, depression or grief, medicines such as sedatives or antidepressants, persistent pain, sleep disorders, and an underactive or overactive thyroid. Long-term conditions such as diabetes, COPD, and heart, liver or kidney disease, infections and recovery from major surgery are also named.

These are contexts to be assessed, not conclusions you can reach yourself. This site has separate pages for the most common ones: anemia and iron deficiency, vitamin B12 deficiency, thyroid problems, sleep apnea, medicines and mood, and ME/CFS.

1,2,3

Realistic expectations

How quickly tiredness improves depends on its cause. Sleep, lifestyle and stress changes can help over weeks, but they will not fix an underlying medical cause, and treatment depends on what is found. If you have made steady changes and are still tired after several weeks, MedlinePlus advises seeing a clinician.

In trials, exercise lowered feelings of fatigue by a small amount and raised energy by a small-to-moderate amount on average. That is a useful change, not a switch, and it does not apply if effort makes your symptoms worse.

2,3,6

Who this applies to

Adults whose tiredness has gone on for a few weeks or more, or who cannot explain it. Pregnancy, breastfeeding, the menopause, older age and long-term conditions each change what is likely and what is safe, so mention them to your clinician. For a child or teenager who is constantly tired, speak to a pediatrician.

If your question is how to build daily energy, morning grogginess, an afternoon dip or mental tiredness, see the linked goal pages instead of repeating them here.

3

Related conditions and symptoms

Anemia and iron deficiency → Vitamin B12 deficiency → Thyroid problems and fatigue → ME/CFS and post-exertional malaise → Sleep apnea → Fatigue from medicines, mood and other health conditions → Prediabetes, type 2 diabetes and metabolic syndrome → Perimenopause and menopause →

A manageable starting plan

An educational starting point, not a personal prescription. Adjust it to your own situation and any advice from your clinician.

Your first actions

  • Book a visit if tiredness has lasted a few weeks, and bring your tiredness diary and medicine list.
  • Keep sleep times, meals and water regular, and cut back on alcohol and late caffeine.
  • Do not start iron, B12 or "adrenal" products before a test.
  • Do not stop any prescribed medicine on your own; ask about a review instead.

Optional additions

  • Add a short daily walk, building slowly, if activity leaves you feeling better rather than worse.
  • Add a relaxation habit and look at which commitments can be shared.
  • Ask a partner or family member whether they notice snoring or breathing pauses.

What to track

  • Energy at morning, midday and evening, and anything that left you worse afterward.
  • Sleep times, naps, caffeine, alcohol and meals.
  • When any medicine or supplement was started.
  • Mood and any new symptoms such as weight change or breathlessness.

When to reassess

Check again after one to two weeks of steady changes and diary notes. If you are still tired after several weeks, or tiredness is getting worse or affecting daily life, see a clinician. Return sooner for any warning sign.

When to seek professional support

  • See a doctor or nurse if tiredness lasts a few weeks or comes with weight loss, mood changes, snoring with gasping, or other symptoms.
  • Ask a pharmacist to review your medicines and supplements.
  • Contact a provider right away for confusion, dizziness, blurred vision, little urine or thoughts of self-harm.

What helps

Ordered by how well the research supports each step. Evidence strength is shown on every card; precautions sit next to the advice.

Start here

Get checked if tiredness has lasted a few weeks

High certainty

Addresses: Finds a treatable cause rather than guessing

Why it may help: MedlinePlus advises contacting a provider if fatigue has lasted weeks without improvement, and the NHS says to see a GP if you have felt tired for a few weeks and are not sure why, if it affects daily life, or if you have other symptoms such as weight loss or mood changes. A provider will usually ask about sleep, daily activities, appetite and exercise, do a physical exam, and may order blood tests for anemia, diabetes, inflammatory diseases and possible infection, plus kidney, liver and thyroid function tests.

How to apply it: Book a visit and describe the pattern in your own words: constant tiredness, sleepiness, weakness, low motivation, or worse after effort. Bring your tiredness diary and a list of every medicine and supplement you take, including over-the-counter products.

Who it may suit: Anyone whose tiredness has lasted a few weeks, is unexplained, or is affecting daily life.

Precautions: A normal test result does not mean your tiredness is not real. Ask what happens next, and return if it continues or changes.

1,2,3

Fatigue: when to get help → Talking with a health professional →

Keep a tiredness diary

Low certainty

Addresses: Shows patterns you and your clinician can act on

Why it may help: MedlinePlus suggests keeping a fatigue diary to find patterns in when you are most and least tired. Patterns such as worse after meals, worse after poor sleep, worse after effort, or worse at one time of month give a clinician clues about where to look.

How to apply it: For one to two weeks, note each day: energy at morning, midday and evening; bedtime and wake time; naps; meals; caffeine and alcohol; medicines; mood; and any activity that left you worse afterward.

Who it may suit: Everyone, whether or not you have seen a clinician yet.

Precautions: The diary is a conversation aid, not a way to diagnose yourself.

2

Look after the basics: regular sleep, regular meals and plenty of water

Moderate certainty

Addresses: Removes the common everyday contributors while you wait for answers

Why it may help: The NHS lists not enough sleep, an unhealthy diet and little exercise among the common causes of tiredness, and suggests the same sleep times each day, aiming for 6 to 9 hours of sleep, relaxing before bed and avoiding caffeine, alcohol and heavy meals close to bedtime. The NHS also says dehydration can cause tiredness, and that most people should drink enough during the day for pale yellow urine.

How to apply it: Keep a steady wake-up time, eat regular balanced meals, drink through the day, and keep screens and caffeine away from bedtime. If you are pregnant, in a hot environment, physically active for long periods or ill, you may need more fluid.

Who it may suit: Most adults with lasting tiredness, alongside (not instead of) a medical check.

Precautions: Habits will not fix a medical cause. If you are still tired after several weeks of steady changes, see a clinician.

3,7,8,9

Everyday habits for energy → Improve Your Sleep Quality → Stay Hydrated for Daily Wellbeing →

Additional options

Gentle, regular movement (if effort does not leave you worse)

Moderate certainty

Addresses: Small average gains in energy and less fatigue

Why it may help: A meta-analysis of 81 randomized studies (7,050 participants) found exercise lowered feelings of fatigue by a small amount, raised energy by a small-to-moderate amount and raised vitality by a moderate amount. The size of the effect was linked to exercise intensity and program length. NHS guidelines for adults suggest building toward regular weekly activity.

How to apply it: Start with what feels comfortable, such as a short daily walk, and build up slowly. Stay within what leaves you feeling better rather than worse the next day.

Who it may suit: People whose tiredness is general and who feel better, not worse, after activity.

Precautions: This advice is not for people with post-exertional malaise (feeling worse after effort, sometimes days later) or long COVID: speak to a GP or specialist before increasing activity. The NHS says people with long COVID should not restart exercise before talking to a GP or specialist.

6,10,5,11

ME/CFS and post-exertional malaise → Improve Your Everyday Stamina →

Cut back on alcohol and on caffeine that spoils sleep

Moderate certainty

Addresses: Removes two common lifestyle contributors

Why it may help: MedlinePlus lists drinking too much alcohol and too much caffeine that spoils sleep among the lifestyle contributors to fatigue. The NHS advises not regularly drinking more than 14 units a week and says there is no safe drinking level.

How to apply it: Move caffeine to the morning, keep alcohol away from the evening, and notice whether you feel better after a few weeks.

Who it may suit: Regular drinkers and heavy tea, coffee or energy-drink users.

Precautions: If you drink heavily every day, speak to a clinician before stopping suddenly. Cutting caffeine suddenly can cause headaches and a temporary dip in energy.

2,1,12

Caffeine and energy drinks → Caffeine, alcohol and sleep →

Make room to relax and ease stressors

Low certainty

Addresses: Eases a common contributor to ongoing tiredness

Why it may help: MedlinePlus suggests learning better ways to relax, keeping a reasonable work and personal schedule, and reducing stressors where possible. The NHS lists stress and life challenges among the common causes of tiredness.

How to apply it: Choose one relaxation habit you can keep, protect time off, and look at which commitments can be shared or reduced.

Who it may suit: People whose tiredness comes with a heavy workload, caring duties or a stressful period.

Precautions: If low mood, constant worry or exhaustion lasts, talk to a clinician rather than only trying to relax more.

1,3

How to relieve stress → Burnout →

Review your medicines and supplements with a pharmacist or prescriber

Moderate certainty

Addresses: Spots a medicine as a possible cause

Why it may help: MedlinePlus lists certain medicines as a cause of fatigue, naming antidepressants, antihistamines and medicines for nausea and pain, and the encyclopedia also names sedatives. It says a provider may adjust the dose or switch the medicine, and warns not to stop or change any medicine without first talking to your provider.

How to apply it: Ask for a medicine review and mention when the tiredness began relative to any new medicine. Bring every product you take, including over-the-counter ones.

Who it may suit: Anyone who started a new medicine, or takes several, around the time the tiredness began.

Precautions: Never stop a prescribed medicine on your own. Do not add stimulants to counter a medicine's drowsiness without asking.

2,1

Fatigue from medicines, mood and other health conditions → Medicines, sleep, mood and memory →

Still being studied

Iron when tiredness is unexplained and ferritin is low (not anemic)

Low certainty

Addresses: Possibly less fatigue in a specific group

Why it may help: In a Swiss randomized trial, 144 non-anemic women aged 18 to 55 with unexplained fatigue took iron or placebo for four weeks. Fatigue fell 29% with iron and 13% with placebo, and the benefit appeared only in women with ferritin (a blood test result) at or below 50 micrograms per liter. This was one four-week trial in women.

How to apply it: Only after a blood test shows low iron stores and a clinician has looked for the reason. The trial used 80 mg a day of elemental iron under study conditions; that is not dosing advice.

Who it may suit: People whose clinician has found low iron or ferritin.

Precautions: Too much iron can harm: in haemochromatosis iron builds up and damages the liver, joints, pancreas and heart, and iron overdose in a young child can be fatal. Anemia can also signal bleeding or another condition that needs finding.

13,14,15

Anemia and iron deficiency →

Asian (Panax) ginseng for general fatigue

Mixed findings

Addresses: Possible small effect on non-disease fatigue

Why it may help: NCCIH says Asian ginseng alone may have a small beneficial effect on general (non-disease) fatigue, though not all research agrees. A 2023 meta-analysis of 19 randomized trials found no significant reduction in fatigue overall, but significant reductions for ginseng herbal formulas and for general fatigue, with small effect sizes.

How to apply it: Studied as oral products. Speak to a pharmacist or clinician first, and do not use it to avoid a medical check.

Who it may suit: Adults without a medical cause who want to try a product after being checked.

Precautions: Insomnia is the most common side effect; it may affect blood sugar and clotting; avoid in pregnancy. Check with a pharmacist if you take any medicine.

16,17

Energy supplements compared →

Vitamin B12 or B complex when you are not deficient

Not enough evidence

Addresses: No clear energy benefit shown

Why it may help: A 2021 systematic review of 16 randomized trials (6,276 people) of B12 or B complex in people without overt deficiency found no effect on cognitive function or depression, and only one study reported unexplained fatigue, so the review could not analyze fatigue. Correcting a true deficiency is a different matter and needs a test and treatment.

How to apply it: Ask for a B12 blood test rather than self-treating.

Who it may suit: People whose tests show B12 is low, treated under clinical advice.

Precautions: Numbness, tingling, balance trouble or confusion need assessment, not self-treatment. Some medicines, including proton pump inhibitors, can affect absorption and test results.

18,19

Vitamin B12 deficiency →

Food & nutrition

Eating regularly and in balance

For most people, food for energy means eating enough, regularly, with variety, not eating a particular superfood. MedlinePlus advises a healthy, balanced diet and plenty of water to reduce fatigue. The NHS Eatwell Guide says you do not need to get the balance right at every meal but over a day or a week.

No food has been shown to cure persistent tiredness. If a blood test finds a deficiency, food changes are best made alongside treatment from your clinician, not instead of it.

1,20

Foods linked to nutrients your clinician may check

These foods supply nutrients that, if low, can contribute to tiredness. Eating them is not a substitute for a test, and extra supplements are not helpful if you are not low.

Iron-rich foods

Moderate certainty

Addresses: Supports iron stores

Why it may help: The NHS and MedlinePlus list red meat, beans, nuts, dried fruit and fortified breakfast cereals as good iron sources; dark-green leafy vegetables also appear on NHS lists. Iron from plants and supplements is harder to absorb, and vitamin C-rich foods help absorption. The NHS lists tea, coffee, dairy and foods high in phytic acid as things that can make absorption harder.

How to apply it: Include iron-rich foods across the week; pair plant iron with a vitamin C food such as fruit; have tea and coffee between meals rather than with them.

Who it may suit: People with low iron on a test, heavy periods, vegetarian or vegan diets, or pregnancy (with clinical guidance).

Precautions: Food will not correct a significant deficiency on its own. If you have haemochromatosis, avoid iron or vitamin C supplements unless your clinician advises.

21,22,14,15

Anemia and iron deficiency → Women's nutrition: iron, folate and calcium →

Vitamin B12 foods

Moderate certainty

Addresses: Supports B12 intake

Why it may help: The NHS lists meat, fish, eggs, dairy products and fortified foods as dietary B12 sources, and says a vegan diet without B12 supplements or fortified foods can lead to low B12.

How to apply it: If you eat no animal foods, ask a clinician or dietitian about fortified foods or a supplement and a blood test.

Who it may suit: Vegans, older adults, people on certain medicines or with absorption conditions.

Precautions: Some causes of low B12 are not about diet (such as pernicious anemia) and need injections or specific treatment. Tingling, numbness or balance problems need assessment.

19

Vitamin B12 deficiency → Fortified foods →

21,19

Fluids, alcohol and caffeine

The NHS says dehydration can cause tiredness, headache and dizziness, and that drinking enough through the day for pale yellow urine is a simple guide. The UK Eatwell Guide suggests 6 to 8 cups or glasses of fluid a day as a guide, and you may need more in heat, illness, pregnancy or long activity.

MedlinePlus lists too much alcohol and too much caffeine that spoils sleep as lifestyle contributors to fatigue. The pages on Hydration and on Support Energy Through Nutrition go into more detail.

8,9,2

Eating too little

Eating too little for how active you are can leave you drained. An International Olympic Committee consensus describes relative energy deficiency in sport as health and performance problems from inadequate energy intake relative to exercise. If you are cutting food heavily or training hard and feel constantly tired, tell your clinician.

23

Remedies & supplements

Traditional use, laboratory findings and human trials are kept apart. "Natural" does not mean safe.

Iron

Moderate certainty

Studied form and route: Oral tablets, prescribed or advised after a blood test shows low iron

Intended outcome: Correcting a proven deficiency

Human evidence: For iron deficiency anemia, the NHS says iron tablets are recommended, usually for about 6 months, with repeat blood tests to check levels return to normal. In one Swiss trial of 144 non-anemic women with unexplained fatigue, fatigue fell 29% with iron versus 13% with placebo, but only in women with low ferritin.

Limits: One four-week trial in women; the benefit depended on low ferritin. It does not show iron helps people with normal levels.

Interactions and precautions: Common side effects are constipation or diarrhea, stomach pain, heartburn, nausea and darker stools. Too much iron can harm, especially in haemochromatosis, and an overdose in a young child can be fatal. Anemia can be a sign of bleeding or another condition that needs finding.

14,13,15

Anemia and iron deficiency → Medicine interactions →

Vitamin B12 and B complex

Not enough evidence

Studied form and route: Injections or tablets for proven deficiency; supplements for others

Intended outcome: Correcting a proven deficiency

Human evidence: The NHS says most B12 deficiency is treated with injections or tablets, injections usually first, for as long as needed. In people who are not deficient, a systematic review of 16 randomized trials could not assess fatigue because only one trial reported it. For ME/CFS, NHS says there is insufficient evidence to recommend supplements such as B12.

Limits: Benefit is established for deficiency only. For others, evidence on tiredness is insufficient.

Interactions and precautions: Do not guess: nerve symptoms need assessment. Some medicines (such as proton pump inhibitors and metformin) can affect absorption or test results; do not stop them without advice. High doses of some B vitamins, such as niacin, can cause harm.

19,18,24

Vitamin B12 deficiency →

Asian (Panax) ginseng

Mixed findings

Studied form and route: Oral extracts and herbal formulas

Intended outcome: Possible small effect on general fatigue

Human evidence: A 2023 meta-analysis of 19 randomized trials found no significant reduction in fatigue overall, but significant reductions for herbal formulas and for general fatigue, with small effects. NCCIH says herbal formulas containing other ingredients may help chronic fatigue but ginseng alone may not, and that not all research agrees.

Limits: Small effects and mixed results; products and formulas differ.

Interactions and precautions: Short-term oral use of up to 6 months appears safe for most people; insomnia is the most common side effect. It may affect blood sugar and clotting and should be avoided in pregnancy. Talk to a pharmacist first if you take any medicine.

16,17

Energy supplements compared →

Rhodiola

Not enough evidence

Studied form and route: Oral herbal extracts

Intended outcome: Physical and mental fatigue (studied)

Human evidence: NCCIH says there is not enough reliable evidence to say whether rhodiola is useful for any health-related purpose. A 2012 systematic review of 11 trials found contradictory results, and all had high risk of bias or reporting flaws.

Limits: Low-to-moderate quality research; no independent replication.

Interactions and precautions: Possibly safe for up to 12 weeks. Side effects include dizziness, headache, insomnia and dry mouth. An interaction with losartan has been reported; check with a pharmacist.

25,26

Energy supplements compared →

"Adrenal support" products

Evidence against

Studied form and route: Over-the-counter blends marketed for adrenal fatigue

Intended outcome: Not supported

Human evidence: A 2016 systematic review concluded that adrenal fatigue is not a recognised medical condition and that the evidence does not support it.

Limits: No evidence that these blends treat tiredness.

Interactions and precautions: Products may contain ingredients not on the label, and one case report describes harm from a supplement with an undeclared glucocorticoid.

27,28

Cortisol, adrenal fatigue and what the science supports →

Therapies & care

Established professional care for lasting tiredness starts with finding the cause, then treating it. This page does not recommend medicines or doses, and you should not stop a prescribed medicine on your own. Treatment depends on the cause and may include talking therapies, sleep advice or lifestyle changes.

A clinical assessment and blood tests

High certainty

Medical care A provider will take a history, usually do a physical exam, and may order blood tests for anemia, diabetes, inflammatory diseases and infection, along with kidney, liver and thyroid tests and a urine test. This is how most of the common treatable causes are found.

Who it may suit: Anyone with tiredness lasting a few weeks, or with any warning sign above.

Precautions: Tests can be normal; if tiredness continues, go back and ask what else could be considered.

1,2,3

Fatigue: when to get help →

Care for the cause that is found

High certainty

Condition-specific treatment Anemia, B12 deficiency, thyroid problems, sleep apnea, depression and other contexts each have their own established care, described on their own pages. For example, the NHS says iron deficiency anemia is treated with iron tablets and follow-up blood tests, an underactive thyroid is usually treated with levothyroxine with regular blood tests, and sleep apnea can be serious if untreated.

Who it may suit: People whose assessment has found a cause.

Precautions: Follow your clinician's advice, and do not self-adjust treatment.

14,19,29,30

Anemia and iron deficiency → Thyroid problems and fatigue → Sleep apnea →

Medicine review

Moderate certainty

Medical and pharmacy care If a medicine may be causing fatigue, MedlinePlus says a provider may adjust the dose or switch the medicine. Antidepressants, antihistamines, sedatives and medicines for nausea and pain are among those named.

Who it may suit: People whose tiredness began around a new medicine or who take several.

Precautions: Do not stop or change any medicine without talking to your provider.

2,1

Fatigue from medicines, mood and other health conditions →

Support for low mood and stress

Moderate certainty

Talking therapies and mental health care MedlinePlus notes that if you have long-term pain or depression, treating it often helps the fatigue. The NHS suggests seeing a GP if low mood lasts most of the day, every day, for more than 2 weeks.

Who it may suit: People whose tiredness comes with low mood, loss of interest, worry or exhaustion from work or caring.

Precautions: If you have thoughts of harming yourself, in the US call or text 988 (free, 24/7); elsewhere use your local emergency number.

1,4

Stress, anxiety, burnout and depression → Burnout →

Specialist care for ME/CFS and long COVID

Mixed findings

Specialist care and pacing There is no specific test for ME/CFS; it is diagnosed from symptoms after other conditions are ruled out. There is currently no cure, but treatments may help manage symptoms. NICE describes energy management (pacing) as a self-management approach that is not curative, and recommends against fixed incremental exercise programs. Sources differ: a Cochrane review found exercise therapy probably reduced fatigue but with a high risk of bias and uncertain harms.

Who it may suit: People who feel worse after effort, or whose fatigue followed an infection and has not settled.

Precautions: Follow individual advice from a clinician experienced in ME/CFS or long COVID before increasing activity.

31,32,33,11

ME/CFS and post-exertional malaise →

What to avoid

Habits, products and claims that can get in the way. Never stop a prescribed medicine without talking to the professional who prescribed it.

Risks that apply to most people

Waiting it out for months

High certainty

Why: MedlinePlus and the NHS both advise getting tiredness checked when it lasts a few weeks. Some causes, such as B12 deficiency, are better treated early because some problems they cause can become permanent.

Who it applies to: Anyone with unexplained tiredness that has gone on for a few weeks or affects daily life.

Try instead: Book a visit and bring your diary and medicine list.

2,3,19

Fatigue: when to get help →

Using caffeine or other stimulants to push through

Moderate certainty

Why: MedlinePlus states that stimulants, including caffeine, are not effective treatments for fatigue and can make the problem worse when they are stopped. Caffeine late in the day can also spoil the sleep you need.

Who it applies to: Regular coffee, tea, cola and energy-drink users.

Try instead: Find the cause; move caffeine to the morning; see the stimulants page.

1,2

Caffeine and energy drinks →

Regular heavy drinking

Moderate certainty

Why: MedlinePlus lists drinking too much alcohol, and regular drug use, among the contributors to fatigue. The NHS advises not drinking more than 14 units a week on a regular basis.

Who it applies to: Anyone who drinks regularly or to wind down.

Try instead: Keep alcohol low and away from bedtime; ask for support if cutting down is hard.

1,12

Personal triggers to check

Pushing harder when effort makes you feel worse afterward

Moderate certainty

Why: Feeling worse after physical or mental activity, sometimes hours or days later and taking days or weeks to recover from, is called post-exertional malaise. NICE recommends against programs with fixed incremental increases in exercise for ME/CFS.

Who it applies to: People who crash after activity, or with long COVID or suspected ME/CFS.

Try instead: Tell your clinician and read about pacing before increasing activity.

5,32

ME/CFS and post-exertional malaise → Balance Activity & Rest →

Ignoring loud snoring or breathing pauses at night

Moderate certainty

Why: The NHS says gasping, snorting or choking noises in sleep, loud snoring and always feeling very tired in the day are reasons to see a GP, and that sleep apnea can be serious if untreated.

Who it applies to: People who snore loudly or are told they stop breathing in their sleep.

Try instead: Ask a partner or family member what they notice and tell your clinician.

30,3

Sleep apnea →

Products that need caution

Starting iron or B12 pills without a test

Moderate certainty

Why: You may not be low, anemia can be a sign of bleeding, kidney disease or another condition, too much iron can harm, and iron overdose in a young child can be fatal. B12 deficiency needs proper treatment because some problems can become irreversible if delayed.

Who it applies to: Anyone tempted to try supplements for tiredness.

Try instead: Ask for a blood test first; keep iron tablets out of reach of children.

34,14,15,19

Anemia and iron deficiency → Vitamin B12 deficiency →

Unlabelled or unregulated "energy" and "adrenal support" products

Low certainty

Why: One published case report describes harm (iatrogenic Cushing syndrome) from a recalled supplement that contained an undeclared glucocorticoid. Products can contain ingredients that are not on the label.

Who it applies to: Anyone buying energy, adrenal or thyroid supplements online.

Try instead: Talk to a pharmacist or clinician before buying; read the product quality page.

28

Product quality and contamination → Energy supplements compared →

Unsupported claims

"Adrenal fatigue" explains all tiredness

Evidence against

Why: A 2016 systematic review concluded that adrenal fatigue as a medical condition is not supported by the evidence. Real adrenal disease exists but is diagnosed by tests and is different.

Who it applies to: Anyone told they have adrenal fatigue after a saliva or home test.

Try instead: Ask your clinician about the standard checks for tiredness.

27

Cortisol, adrenal fatigue and what the science supports →

"Tiredness with a slightly abnormal thyroid test means thyroid pills will fix it"

Moderate certainty

Why: In a secondary analysis of a randomized trial of 638 adults aged 65 or older with persistent subclinical hypothyroidism and greater symptom burden, levothyroxine did not improve hypothyroid symptoms or tiredness over one year compared with placebo.

Who it applies to: Older adults with mildly raised TSH and normal thyroxine.

Try instead: Discuss your results with your doctor; do not self-treat with thyroid supplements.

35,29

Thyroid problems and fatigue →

Common mistakes

Stopping a prescribed medicine because you think it causes tiredness

High certainty

Why: MedlinePlus warns not to stop or change any medicine without first talking to your provider. A dose change or switch is a decision for the prescriber.

Who it applies to: Anyone who takes regular medicines.

Try instead: Book a medicine review and describe the timing of your tiredness.

1

Fatigue from medicines, mood and other health conditions →

Assuming low mood or stress is "just in your head", or that tiredness is only about sleep

Moderate certainty

Why: Lack of energy, disturbed sleep and no motivation are listed among the symptoms of depression, and the NHS suggests seeing a GP if symptoms last most of the day, every day, for more than 2 weeks. Equally, medical causes can sit alongside poor sleep.

Who it applies to: Anyone whose tiredness comes with low mood, loss of interest or worry.

Try instead: Tell your clinician about mood and sleep as well as energy.

4,1

Stress, anxiety, burnout and depression →

Evidence & safety

What the research shows

Health agencies agree that lasting or unexplained tiredness should be checked, that causes range from sleep, stress and lifestyle to anemia, thyroid problems, medicines, mood, sleep apnea and other illnesses, and that treatment depends on the cause. Lifestyle steps have modest, general benefits. Supplements help when a deficiency is proven; for people who are not deficient, evidence for iron, B12, ginseng and rhodiola ranges from limited to insufficient, and "adrenal fatigue" is not supported.

Limits of the evidence

  • Fatigue is a symptom with many causes, so most trials look at specific groups, and results may not apply to you.
  • The iron trial was a single four-week study in women; the thyroid analysis was of older adults only.
  • Supplement reviews included small trials at high risk of bias.
  • Self-reported tiredness is hard to measure, and exercise evidence does not apply to people with post-exertional malaise.
  • Sources differ on exercise therapy for ME/CFS.

Precautions and interactions

  • Check supplements and herbs with a pharmacist if you take any medicine.
  • Too much iron can harm, and iron overdose in a young child can be fatal; keep tablets out of reach.
  • Do not use caffeine or stimulants to cover tiredness that needs a check.
  • Never stop a prescribed medicine without speaking to your prescriber.

Life-stage considerations

  • Pregnancy and breastfeeding: tiredness is common, and anemia is a common reason; speak to a midwife or doctor before taking supplements or herbs such as ginseng.
  • Menopause and hormonal change: the NHS lists hormonal changes among common causes; raise it with a clinician.
  • Older adults: B12 deficiency is more common (the NHS reports it in about 1 in 10 people aged 75 or over), medicines are more likely to contribute, and thyroid results need careful interpretation.
  • Children and teenagers: speak to a pediatrician about constant tiredness; do not give supplements or herbs without advice.

Warning signs

  • Confusion or dizziness, blurred vision, little or no urine, or recent swelling and weight gain: contact a provider right away.
  • Unusual tiredness with dizziness that does not go away, dark urine or passing little urine: urgent appointment or NHS 111 in the UK.
  • Difficulty breathing, confusion, cold or pale skin, or being very hard to wake: emergency care.
  • Loud snoring with gasping or choking in sleep.
  • Unintentional weight loss, fever or regular sweats with fatigue.
  • Thoughts of harming yourself: in the US call or text 988 (free, 24/7); elsewhere use your local emergency number.

Claim checks

Caffeine is a good fix for tiredness

Evidence against

MedlinePlus states stimulants, including caffeine, are not effective treatments for fatigue and can make it worse when stopped.

1

Take iron or B12 to see if it helps

Mixed findings

Test first. Tiredness has many causes, anemia can be a sign of something else, too much iron can harm, and B12 deficiency needs proper treatment. One trial found iron helped non-anemic women only when ferritin was low.

34,15,19,13

Adrenal fatigue is why I am so tired

Evidence against

A 2016 systematic review concluded that adrenal fatigue is not supported by the evidence.

27

Exercise always helps tiredness

Mixed findings

On average it lowered fatigue and raised energy in trials, but if activity makes your symptoms worse, sometimes days later, that pattern needs a clinician and a different approach.

6,5,32

Tiredness is normal, I just need to push on

High certainty

Some tiredness is normal, but tiredness that lasts a few weeks without a clear reason, or affects daily life, is a reason to be checked.

3,2

Questions people ask

Is it normal to feel tired all the time?

It is normal to feel tired sometimes. Being tired all the time with no known reason can be a sign of a problem, so it is worth getting checked.

What is the difference between fatigue and sleepiness?

Sleepiness is the need to sleep. Fatigue is a lack of energy and motivation, and the two can occur together.

How long is too long to be tired?

MedlinePlus advises contacting a provider if fatigue lasts for weeks, and the NHS suggests seeing a GP if you have felt tired for a few weeks and are not sure why.

Which tests are used for unexplained tiredness?

Blood tests to check for anemia, diabetes, inflammatory diseases and possible infection, along with kidney, liver and thyroid function tests and a urine test, may be ordered. Your clinician decides which are right for you.

Can caffeine fix tiredness?

Not as a treatment. MedlinePlus says stimulants such as caffeine are not effective treatments for fatigue and can make the problem worse when they are stopped.

Does being tired mean I have low iron?

No. Tiredness has many causes, and only a blood test can show whether iron or red blood cells are low. Test first rather than taking iron to see.

Could my medicine be making me tired?

Yes, some can, including certain antidepressants, antihistamines, sedatives and medicines for nausea and pain. Do not stop any medicine without talking to your provider.

Can depression or stress cause tiredness?

Yes. Lack of energy, disturbed sleep and no motivation are listed among the symptoms of depression, and stress is a common cause of tiredness. If low mood lasts most of the day, every day, for more than 2 weeks, the NHS suggests seeing a GP.

What if I feel worse after activity?

Feeling worse after physical or mental activity, sometimes hours or days later, is called post-exertional malaise. Tell your clinician clearly, and read about ME/CFS before increasing activity.

Can a thyroid problem make me tired?

Yes. Extreme tiredness is a common symptom of an underactive thyroid, and persistent tiredness and weakness can occur with an overactive one. It is checked with blood tests, not symptoms.

Is "adrenal fatigue" a real diagnosis?

A 2016 systematic review concluded that adrenal fatigue is not supported by the evidence. Real adrenal disease exists but is diagnosed through medical tests.

References

  1. MedlinePlus Medical Encyclopedia. Fatigue (review date 5/19/2025). Read 2026-10-22. source
  2. MedlinePlus. Fatigue (health topic). Read 2026-10-22. source
  3. NHS. Tiredness and fatigue (page last reviewed 2 June 2023). Read 2026-10-22. source
  4. NHS. Symptoms of depression in adults (page last reviewed 5 July 2023). Read 2026-10-22. source
  5. NHS. ME/CFS: Symptoms (page last reviewed 28 May 2024). Read 2026-10-22. source
  6. The effect of chronic exercise on energy and fatigue states: a systematic review and meta-analysis of randomized trials. Front Psychol. 2022. PMID 35726269. source
  7. NHS Every Mind Matters. How to fall asleep faster and sleep better. Read 2026-10-22. source
  8. NHS. Dehydration (page last reviewed 1 May 2026). Read 2026-10-22. source
  9. NHS. Water, drinks and hydration (page last reviewed 17 May 2023). Read 2026-10-22. source
  10. NHS. Physical activity guidelines for adults aged 19 to 64 (page last reviewed 22 May 2024). Read 2026-10-22. source
  11. NHS. Long COVID (page last reviewed 19 August 2025). Read 2026-10-22. source
  12. NHS. The risks of drinking too much. Read 2026-10-22. source
  13. Iron supplementation for unexplained fatigue in non-anaemic women: double blind randomised placebo controlled trial. BMJ. 2003. PMID 12763985. source
  14. NHS. Iron deficiency anaemia (page last reviewed 26 January 2024). Read 2026-10-22. source
  15. NHS. Haemochromatosis (page last reviewed 29 March 2023). Read 2026-10-22. source
  16. Ginseng and ginseng herbal formulas for symptomatic management of fatigue: a systematic review and meta-analysis. J Integr Complement Med. 2023. PMID 36730693. source
  17. NCCIH, NIH. Asian Ginseng: Usefulness and Safety. Read 2026-10-22. source
  18. Effects of vitamin B12 supplementation on cognitive function, depressive symptoms, and fatigue: a systematic review, meta-analysis, and meta-regression. Nutrients. 2021. PMID 33809274. source
  19. NHS. Vitamin B12 or folate deficiency anaemia (page last reviewed 20 February 2023). Read 2026-10-22. source
  20. NHS. The Eatwell Guide. Read 2026-10-22. source
  21. NHS. Vitamins and minerals: Iron (page last reviewed 3 August 2020). Read 2026-10-22. source
  22. MedlinePlus Medical Encyclopedia. Iron in diet. Read 2026-10-22. source
  23. 2023 International Olympic Committee consensus statement on Relative Energy Deficiency in Sport (REDs). Br J Sports Med. 2023. PMID 37752011. source
  24. NHS. ME/CFS: Treatment (page last reviewed 28 May 2024). Read 2026-10-22. source
  25. NCCIH, NIH. Rhodiola: Usefulness and Safety. Read 2026-10-22. source
  26. Rhodiola rosea for physical and mental fatigue: a systematic review. BMC Complement Altern Med. 2012. PMID 22643043. source
  27. Adrenal fatigue does not exist: a systematic review. BMC Endocr Disord. 2016. PMID 27557747. source
  28. Iatrogenic Cushing syndrome from an adulterated glucocorticoid-containing supplement. JCEM Case Rep. 2026. PMID 42833837 (case report, cited from the site's existing page; not re-verified in this round). source
  29. NHS. Underactive thyroid (hypothyroidism) (page last reviewed 28 April 2025). Read 2026-10-22. source
  30. NHS. Sleep apnoea (page last reviewed 11 May 2026). Read 2026-10-22. source
  31. NHS. Myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS) (page last reviewed 28 May 2024). Read 2026-10-22. source
  32. NICE. Myalgic encephalomyelitis (or encephalopathy)/chronic fatigue syndrome: diagnosis and management (NG206), Recommendations (published 29 October 2021). Read 2026-10-22. source
  33. Exercise therapy for chronic fatigue syndrome. Cochrane Database Syst Rev. 2024 (original 2019; searches to 2014). PMID 39697147. source
  34. NHLBI, NIH. Anemia: What is anemia? (last updated March 24, 2022). Read 2026-10-22. source
  35. L-thyroxine therapy for older adults with subclinical hypothyroidism and hypothyroid symptoms: secondary analysis of a randomized trial. Ann Intern Med. 2020. PMID 32365355. source

Related on AlternativeMed

Related goals

Have More Energy Throughout the Day → Feel More Energetic in the Morning → Manage Afternoon Energy Slumps → Improve Your Everyday Stamina → Reduce Mental Fatigue → Support Energy Through Nutrition → Stay Hydrated for Daily Wellbeing → Balance Activity & Rest → Manage Energy Without Relying on Stimulants → Wake Up Feeling Rested →

Ingredients, foods and supplements

Energy supplements compared → Cortisol, adrenal fatigue and what the science supports → Fortified foods →

Research, safety and claim-check resources

Fatigue: when to get help → Everyday habits for energy → Energy and vitality research and evidence → Medicines, sleep, mood and memory → Stress, anxiety, burnout and depression → Medicine interactions → Talking with a health professional →