13 Possible Reasons Why You're Tired All the Time

Low on energy? It may not be depression

Table of Contents
View All
Table of Contents

Depression is a common cause of fatigue, so you might be wondering whether your fatigue is a result of depression. But just because you're tired all the time doesn't necessarily mean that you're depressed.

The fact is there are many underlying conditions that could be responsible for feeling tired all the time. From mood disorders to issues affecting your physical health like chronic fatigue syndrome, the following psychiatric and medical conditions are some of the most common ailments associated with fatigue.

But first, it's important to note that many of these conditions share symptoms similar to depression, so we'll start there. By understanding the distinctions between depression and other factors that cause fatigue, you can seek out the right treatment and start to feel like your energetic self again.

Illnesses that cause depression-like symptoms

Verywell / Nusha Ashjaee

Psychiatric Factors


Depression, which research suggests is associated with an imbalance of neurotransmitters in the brain, is commonly linked with fatigue. The condition is also associated with disturbed sleep, which can also significantly contribute to tiredness. While some people may have difficulty falling asleep or staying asleep, others may oversleep. Both of these sleep disturbances can leave you feeling apathetic and sluggish.

Other symptoms associated with depression include:

  • Appetite and/or weight changes
  • Difficulty thinking, concentrating, or making decisions
  • Fatigue or loss of energy
  • Feelings of guilt or worthlessness
  • Lack of interest in activities normally enjoyed
  • Persistent sad, anxious, or “empty” mood
  • Thoughts of death or suicide

If you are having suicidal thoughts, contact the National Suicide Prevention Lifeline at 988 for support and assistance from a trained counselor. If you or a loved one are in immediate danger, call 911. 

For more mental health resources, see our National Helpline Database.

If you think you may be experiencing depression, talk to your doctor. They can refer you to a therapist who can help you manage your emotions or another mental health professional such as a psychiatrist who may also recommend antidepressants. Don't let depression go untreated.


Anxiety and anxiety disorders are often associated with worry and nervousness, which can lead to sleep disturbances. But sleep deprivation may also contribute to feelings of anxiety, which perpetuates a cycle of both anxiety and sleeplessness. This, of course, can make it difficult to manage both conditions.

If you are constantly tired because you haven’t been sleeping, your anxiety levels about not sleeping may increase as a result.

According to the National Sleep Foundation, the following anxiety disorders may be associated with sleep disorders that cause fatigue:

Sleep problems like insomnia may also contribute to the development of anxiety disorders, especially if left untreated.

If you're concerned that your anxiety may be contributing to your lack of energy and fatigue, talk to your doctor about your options, which may include medication, therapy, or a combination of both.


Stress can lead to sleepless nights. Stress can also wear you down and cause you to feel fatigued. We've all experienced the repercussions of stress at one time or another. If left unmanaged, stress can also wreak havoc on your mood. Stress can be a trigger for depression and anxiety disorders.

Like anxiety, stress can contribute to poor sleep and poor sleep can create stress. For instance, you know that you need to get a good night's sleep so that you have energy the next day, but you might have trouble falling asleep because you are worried that you aren't going to get enough sleep.

Fortunately, there are many ways to combat stress that don't require sleep aids or medications, unless your stress is severe. Yoga nidra, or "yogic sleep," and meditation are evidence-based tools to help you manage stress and sleep better so you can wake up feeling refreshed with more energy.

Bipolar Disorder

Bipolar disorder is characterized by extreme mood swings, which can contribute to sleep disturbances. Insomnia, nightmares, and erratic sleep-wake cycles are common among people with bipolar disorder, causing fatigue and general tiredness.

If you have bipolar disorder and are experiencing sleep disturbances, talk to your doctor about appropriate treatment for these symptoms.

Attention-Deficit/Hyperactivity Disorder

Attention-deficit/hyperactivity disorder (ADHD) is a common psychiatric condition among both children and adults and is commonly associated with sleep disturbances. Those with ADHD may experience sleep problems including difficulty falling or staying asleep, difficulty waking, and daytime sleepiness and fatigue. Many of the medications used to treat ADHD can also impact sleep.

Sleep patterns and habits are usually assessed when treating ADHD. In fact, research has shown that interventions to improve sleep hygiene can help reduce the severity of ADHD symptoms and increase the person's overall quality of life.

Physical Health Factors

Often, physical health issues such as thyroid problems and chronic fatigue syndrome can result in fatigue symptoms resembling depression. It's also possible that fibromyalgia, sleep apnea, or an autoimmune disorder such as rheumatoid arthritis or lupus could cause you to feel tired all the time.

Here are the physical factors that could be draining your energy and what you can do about it.

Underactive Thyroid

If you have an underactive thyroid (hypothyroidism) simple activities can leave you feeling wiped out. Your thyroid is a small gland in the front of your neck that produces hormones that regulate your metabolism. When it's not producing enough hormones, your metabolism slows down. This can lead to fatigue, weight gain, and even depression.

Some research suggests that up to 69% of people with hypothyroidism experience symptoms of depression.

The traditional treatment for hypothyroidism involves medications that increase thyroid levels in your body. Symptoms of fatigue may get better or go away once the thyroid condition has been treated appropriately with medication. To confirm the diagnosis, your doctor will use blood tests to look at your levels of thyroid hormones including thyroxine and thyroid-stimulating hormone (TSH).

Chronic Fatigue Syndrome

Chronic fatigue syndrome, now known as myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), is a condition characterized by extreme and persistent fatigue. The fatigue, which lasts at least six months, is often accompanied by memory problems, headaches, and muscle and joint aches.

Those with chronic fatigue still have an interest in activities but lack the energy to do them. Because CFS shares symptoms with other medical and psychiatric illnesses, it is not uncommon for it to be misdiagnosed as depression or another condition. People may also experience both CFS and a psychiatric condition at the same time.

The underlying cause of chronic fatigue syndrome is not yet fully understood, and treatment may involve certain medications and lifestyle interventions.


Fibromyalgia seems to overlap with chronic fatigue, but people with this disorder also have chronic pain all over their bodies. The disorder is usually diagnosed by tender points in certain muscles that respond with pain when touched a certain way. Sleep disturbance is also common in chronic fatigue and fibromyalgia. Research is ongoing into the causes of fibromyalgia. 

Estimates suggest that 40% of people with fibromyalgia also have a co-occurring major depressive disorder.

There is no specific test that can diagnose fibromyalgia. Instead, doctors must rely on an assessment of your health history and symptoms. Diagnosis typically requires the presence of widespread chronic pain, fatigue, and sleep disturbance. Treatment for fibromyalgia usually involves a combination of medication and lifestyle changes.

Autoimmune Disorders

Autoimmune disorders involve the immune system attacking the body. Rheumatoid arthritis, lupus, and celiac disease are examples of autoimmune disorders. Autoimmune processes have also been implicated in diabetes and multiple sclerosis (MS).

While these conditions aren't as common as depression, they can present with similar symptoms. In fact, depression-like symptoms are a hallmark of autoimmune disorders. These symptoms typically emerge over the course of the disease and are associated with psychosocial factors, chronic pain, and long periods of disability.

Dealing with an autoimmune disorder can also increase your risk of developing depression. Results of one large study showed that autoimmune disease increased the subsequent risk of depression by 45%.

Sleep Apnea

Sleep disorders, such as obstructive sleep apnea, can also cause many symptoms similar to those of depression. Obstructive sleep apnea is a condition where your breathing is interrupted during sleep, sometimes for longer than 10 seconds. This can happen as many as 20 or more times an hour.

These frequent interruptions interfere with your sleep quality, resulting in daytime fatigue, morning headaches, and poor concentration. It can also have a serious impact on your mood. One study found that approximately 46% of people with sleep apnea have symptoms of depression.

If you think you have a sleep disorder, speak with your doctor. In addition to reviewing your symptoms, your doctor will likely take your medical history, conduct a physical exam, and may recommend a sleep study. They may also order additional tests to rule out other medical conditions that may be causing your symptoms.

Iron-Deficiency Anemia

The fatigue caused by iron-deficiency anemia is the result of a lack of red blood cells. Your body uses iron to make hemoglobin, the part of the red blood cell that carries oxygen to all the parts of your body.

When you don't have enough iron, your blood can't carry enough oxygen to your body. This can leave you feeling sluggish, irritable, and unable to focus. You may also have dull or pale skin and experience headaches, dizziness, and shortness of breath. 

There are many potential causes that can lead to anemia aside from iron deficiency, so your doctor may ask you further questions about your diet and lifestyle and order more tests if needed.

Dehydration and Inadequate Nutrition

Staying hydrated and getting proper nutrition is important for keeping your energy levels up. Research shows that a lack of fluid intake is associated with increased sleeplessness, fatigue, and irritability.

Not getting enough calories in your diet can also leave you feeling tired all the time, as can eating too many refined carbohydrates or not getting enough protein. Allergies to foods such as wheat, peanuts, or dairy may also contribute to tiredness.

Lifestyle Factors

If you don't seem to have enough energy, it could be because you're not getting enough physical activity. Research shows a sedentary lifestyle can lead to fatigue and difficulty sleeping.

Cigarettes and alcohol can also affect sleep quality and leave you feeling groggy the next day.

Tips for More Energy

Depending on the severity of your symptoms and whether you've been diagnosed with a psychiatric or medical condition, there are a few habits anyone can do to improve their quality of sleep and have more energy the next day.

  • Exercise regularly. There's plenty of evidence to show that regular exercise is good for your mental and physical health. You'll have more energy and sleep better, too.
  • Take short naps. Tired as you may be, sleeping too much during the day can affect your ability to fall or stay asleep at night. Taking short, 20- to 30-minute naps can give you a quick burst of rest without hindering your ability to fall asleep at bedtime.
  • Establish a bedtime routine. Prepare for slumber each night with rituals to help you unwind. Take a hot shower or bath, read a paperback book, or meditate to calm your body and mind. Follow your bedtime routine each night to set the stage for a solid night’s sleep. Be sure to make your bedroom as dark as possible, too.
  • Avoid caffeine, alcohol, and other stimulants before bed. Drinking coffee, soda, or other caffeinated beverages in the late afternoon or evening can make it difficult to fall asleep and stay asleep, as can drinking alcohol. If you smoke cigarettes, consider quitting.
  • Power down your devices. Leave the screens in another room. Scrolling before bedtime can make it more difficult for your mind to wind down and prepare for sleep. Make the bedroom a no-phone zone, if possible.

Press Play for Advice On Sleep Hygiene

Hosted by Editor-in-Chief and therapist Amy Morin, LCSW, this episode of The Verywell Mind Podcast, featuring neurologist and sleep expert Chris Winter, shares strategies for sleeping better at night. Click below to listen now.

Subscribe Now: Apple Podcasts / Spotify / Google Podcasts

A Word From Verywell

While depression remains one of the most common causes of symptoms like tiredness and fatigue, it's not the only condition that produces depression-like symptoms, which underscores the importance of seeking a proper diagnosis. It's also possible to have more than one diagnosis (known as comorbidity) with overlapping symptoms.

For example, there are people who have both clinical depression and hypothyroidism. If you're tired all the time and low on energy, your best bet is to work with your healthcare provider to explore your symptoms and get an official diagnosis.

33 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Ghanean H, Ceniti AK, Kennedy SH. Fatigue in patients with major depressive disorder: Prevalence, burden and pharmacological approaches to management. CNS Drugs. 2018;32(1):65-74. doi:10.1007/s40263-018-0490-z

  2. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. American Psychiatric Association; 2013.

  3. The Sleep Foundation. Anxiety and sleep.

  4. Timpano KR, Carbonella JY, Bernert RA, Schmidt NB. Obsessive compulsive symptoms and sleep difficulties: Exploring the unique relationship between insomnia and obsessionsJ Psychiatr Res. 2014;57:101-7. doi:10.1016/j.jpsychires.2014.06.021 

  5. Krystal AD, Prather AA, Ashbrook LH. The assessment and management of insomnia: An updateWorld Psychiatry. 2019;18(3):337-352. doi:10.1002/wps.20674

  6. Enns MW, Bernstein CN, Kroeker K, et al. The association of fatigue, pain, depression and anxiety with work and activity impairment in immune mediated inflammatory diseasesPLoS One. 2018;13(6):e0198975. doi:10.1371/journal.pone.0198975

  7. Datta K, Tripathi M, Mallick HN. Yoga nidra: An innovative approach for management of chronic insomnia- A case reportSleep Sci Pract. 2017;1(7). doi:10.1186/s41606-017-0009-4

  8. Gold AK, Sylvia LG. The role of sleep in bipolar disorderNat Sci Sleep. 2016;8:207-214. doi:10.2147/NSS.S85754

  9. Peppers KH, Eisbach S, Atkins S, Poole JM, Derouin A. An intervention to promote sleep and reduce adhd symptomsJ Pediatr Health Care. 2016;30(6):e43-e48. doi:10.1016/j.pedhc.2016.07.008

  10. Vassend O, Røysamb E, Nielsen CS, Czajkowski NO. Fatigue symptoms in relation to neuroticism, anxiety-depression, and musculoskeletal pain. A longitudinal twin studyPLoS One. 2018;13(6):e0198594. doi:10.1371/journal.pone.0198594

  11. Gaitonde DY, Rowley KD, Sweeney LB. Hypothyroidism: An update. Am Fam Physician. 2012;86(3):244-251.

  12. Hage MP, Azar ST. The link between thyroid function and depression. J Thyroid Res. 2012;2012:590648. doi:10.1155/2012/590648

  13. Roberts D. Chronic fatigue syndrome and quality of life. Patient Relat Outcome Meas. 2018;9:253-262. doi:10.2147/PROM.S155642

  14. Yancey JR, Thomas SM. Chronic fatigue syndrome: Diagnosis and treatment. Am Fam Physician. 2012;86(8):741-746.

  15. Bellato E, Marini E, Castoldi F, et al. Fibromyalgia syndrome: Etiology, pathogenesis, diagnosis, and treatment. Pain Res Treat. 2012;2012:426130. doi:10.1155/2012/426130

  16. Gracely, RH, Ceko, M, and Bushness, MC. Fibromyalgia and depression. Pain Res Treat. 2012; 486590. doi:10.1155/2012/486590

  17. Kodner C. Common questions about the diagnosis and management of fibromyalgia. Am Fam Physician. 2015;91(7):472-478.

  18. Pryce CR, Fontana A. Depression in autoimmune diseases. Curr Top Behav Neurosci. 2017;31:139-154. doi:10.1007/7854_2016_7

  19. Yanjun L, Tang X. Depressive syndromes in autoimmune disorders of the nervous system: Prevalence, etiology, and influence. Frontiers in Psychiatry. 2018;9:451. doi:10.3389/fpsyt.2018.00451

  20. Benros ME, Waltoft BL, Nordentoft M, et al. Autoimmune diseases and severe infections as risk factors for mood disorders: A nationwide study. JAMA Psychiatry. 2013;70(8):812-820. doi:10.1001/jamapsychiatry.2013.1111

  21. Ejaz SM, Khawaja IS, Bhatia S, Hurwitz TD. Obstructive sleep apnea and depression: A review. Innov Clin Neurosci. 2011;8(8):17-25.

  22. Rezaeitalab F, Moharrari F, Saberi S, Asadpour H, Rezaeetalab F. The correlation of anxiety and depression with obstructive sleep apnea syndrome. J Res Med Sci. 2014;19(3):205-10.

  23. Semelka M, Wilson J, Floyd R. Diagnosis and treatment of obstructive sleep apnea in adults. Am Fam Physician. 2016;94(5):355-360.

  24. Pross N, Demazières A, Girard N, et al. Influence of progressive fluid restriction on mood and physiological markers of dehydration in womenBr J Nutr. 2013;109(2):313-321. doi:10.1017/S0007114512001080

  25. Pezeshki A, Zapata RC, Singh A, Yee NJ, Chelikani PK. Low protein diets produce divergent effects on energy balanceSci Rep. 2016;6:25145. doi:10.1038/srep25145

  26. Yu W, Freeland DMH, Nadeau KC. Food allergy: immune mechanisms, diagnosis and immunotherapyNat Rev Immunol. 2016;16(12):751-765. doi:10.1038/nri.2016.111

  27. Irish LA, Kline CE, Gunn HE, Buysse DJ, Hall MH. The role of sleep hygiene in promoting public health: A review of empirical evidence. Sleep Med Rev. 2015;22:23-36. doi:10.1016/j.smrv.2014.10.001

  28. Harvard Health Publishing. Tips for beating anxiety to get a better night’s sleep.

  29. Herbert C, Meixner F, Wiebking C, Gilg V. Regular physical activity, short-term exercise, mental health, and well-being among university students: The results of an online and a laboratory studyFront Psychol. 2020;11:509. doi:10.3389/fpsyg.2020.00509

  30. Ogeil RP, Phillips JG. Commonly used stimulants: Sleep problems, dependence and psychological distressDrug Alcohol Depend. 2015;153:145-151. doi:10.1016/j.drugalcdep.2015.05.036

By Leonard Holmes, PhD
Leonard Holmes, PhD, is a pioneer of the online therapy field and a clinical psychologist specializing in chronic pain and anxiety.