What is Fatigue?

According to a National Health Interview Survey, over 15% of women and 10% of men in the United States experience fatigue. Fatigue is a lack of mental or physical energy, low interest or motivation, and increased tiredness.

Common types of fatigue

There are various types of fatigue, commonly classified by the duration of symptoms, including:

• Acute fatigue: less than one month

• Subacute fatigue: one to six months

• Chronic fatigue: over six months*

**Chronic fatigue syndrome (CFS), also known as myalgic encephalomyelitis (ME), is characterized by debilitating fatigue and symptoms lasting over six months.

A diagnosis of CFS/ME requires eliminating other possible causes of fatigue and identifying the following symptoms:

• Cognitive impairment, pain, and/or sleep disturbances

• Exhaustion following exertion

• Immune, gastrointestinal, or genitourinary symptoms (e.g., longer recovery from infection, flu-like symptoms, and environmental or food sensitivities)

• Symptoms of energy production or energy transportation impairment (e.g., respiratory fatigue, intolerance to extreme temperature)

Signs, symptoms, and complications

Symptoms of fatigue can range from mild to severe and significantly affect the quality of life. There are several possible mental and physical symptoms of fatigue.

1. Mental symptoms include- Difficulty concentrating - Impaired memory - Sleep issues.

2. Physical symptoms include- Lowered physical stamina - Weakness - Weight loss or gain.

Causes and risk factors

While CFS/ME has no known cause, fatigue may be associated with various underlying health conditions or result from certain dietary and lifestyle habits, including:

• Certain health conditions (e.g., acquired immunodeficiency syndrome (AIDS), cancer, dementia, fibromyalgia, heart failure, multiple sclerosis (MS), Parkinson’s disease)

• Certain medications (e.g., antihistamines, antidepressants, painkillers)

• Depression and/or anxiety

• Dysfunction of mitochondria (organelles in body cells that produce energy)

• Endocrine (hormonal) conditions (e.g., adrenal insufficiency, hypothyroidism)

• Excessive caffeine or alcohol intake

• Nutritional deficiencies (e.g., B vitamins, iron, magnesium)

• Sleep deprivation, insomnia

• Traumatic brain injury (TBI)

Preventing and addressing fatigue

Various dietary and lifestyle approaches may improve energy levels and fatigue. Remember that fatigue treatment often requires addressing factors that contribute to your experience of fatigue, such as treating an associated health condition.

Diet

Dietary Components	Function	Dietary Sources
B Vitamins	Support reactions that convert the energy from food to usable energy	Beef liver Dairy products (e.g., milk, yogurt) Eggs Fish and seafood (e.g., clams, tuna) Legumes Meat (e.g., pork, poultry)
Coenzyme Q10 (CoQ10)	A component of the energy production process in the mitochondria	Broccoli Cauliflower Meat (e.g., beef, pork) Oily fish (e.g., herring, sardines, trout) Oranges Organ meats (e.g., heart, liver, kidney)
Iron	Essential for oxygen transport in the blood; used in enzymes required for cellular energy production	Dark chocolate Legumes (e.g., beans, lentils, soy products) Oysters Spinach
Magnesium	Required for cellular energy production; mitochondria store high levels of magnesium.	Dark chocolate Legumes (e.g., beans, lentils, soy products) Oysters Spinach
Omega-3 (DHA/EHA) Fatty Acids	The structural component of cell membranes; support cognitive and cardiovascular function.	Chia seeds Fish (e.g., herring, mackerel, salmon, sardines) Flax seeds Walnuts
Vitamin C	It acts as an antioxidant; vitamin C deficiency can lead to altered mitochondrial function.	Bell peppers Broccoli Brussels sprouts Citrus fruit (e.g., grapefruit, oranges) Strawberries

Physical activity

Research shows that regular low- to moderate-intensity aerobic exercise (three times per week over several weeks) can help mitigate fatigue and increase energy. Examples of low- and moderate-intensity activities include cycling, swimming, and walking...

Sleep

The National Institutes of Health (NIH) recommends that adults sleep at least seven to eight hours per night. Maintaining consistent sleep and wake times and practicing proper sleep hygiene, such as dimming lights and limiting screen time in the evenings, can help improve your sleep.

Stress management

Studies suggest that mindfulness interventions, such as one that combines mindfulness-based cognitive therapy (MBCT), physical exercise, and stress management, are associated with reduced fatigue in individuals with chronic fatigue syndrome.

Other lifestyle considerations

Minimizing reliance on stimulants, such as sugar, coffee, tea, and energy drinks, can help maintain balanced energy levels. While stimulants temporarily increase energy levels, long-term consumption can negatively affect sleep quality and fatigue. Limiting alcohol consumption can also improve sleep and energy. Although alcohol does cause drowsiness, its consumption interferes with hormones and neurotransmitters essential to sleep quality, such as melatonin and gamma-aminobutyric acid (GABA-neurotransmitter).

References

1. An, J. H., Kim, Y. J., Kim, K. J., Kim, S. H., Kim, N. H., Kim, H. Y., … & Kim, S. G. (2016). L-carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: a randomized, double-blind, placebo-controlled trial. Endocrine Journal, 63(10), 885–895.

2. Ballesio, A., Aquino, M. R. J. V., Feige, B., Johann, A. F., Kyle, S. D., Spiegelhalder, K., … & Baglioni, C. (2018). The effectiveness of behavioral and cognitive behavioral therapies for insomnia on depressive and fatigue symptoms: A systematic review and network meta-analysis. Sleep Medicine Reviews, 37, 114–129.

3. Bhargava, J., & Hurley, J. A. (2020). Fibromyalgia. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih. gov/books/NBK540974/

4. Centers for Disease Control and Prevention. (2013, April 12). QuickStats: Percentage of adults who often felt very tired or exhausted in the past 3 months,* by sex and age group - National Health Interview Survey, United States, 2010-2011†. https://www.cdc.gov/mmwr/preview/ mmwrhtml/mm6214a5.htm

5. Finsterer, J., & Mahjoub, S. Z. (2014). Fatigue in healthy and diseased individuals. The American Journal of Hospice & Palliative Care, 31(5), 562–575.

6. Geoghegan, P., O’Donovan, M. T., & Lawlor, B. A. (2012). Investigation of the effects of alcohol on sleep using actigraphy. Alcohol and Alcoholism, 47(5), 538–544.

7. Greenberg, D. B. (2002). Clinical dimensions of fatigue. Primary Care Companion to the Journal of Clinical Psychiatry, 4(3), 90–93.

8. Hanson, J. A., & Huecker, M. R. (2020). Sleep deprivation. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih. gov/books/NBK547676/

9. Haß, U., Herpich, C., & Norman, K. (2019). Anti-inflammatory diets and fatigue. Nutrients, 11(10).

10. Huskisson, E., Maggini, S., & Ruf, M. (2007). The role of vitamins and minerals in energy metabolism and well-being. The Journal of International Medical Research, 35(3), 277–289.

11. Irish, L. A., Kline, C. E., Gunn, H. E., Buysse, D. J., & Hall, M. H. (2015). The role of sleep hygiene in promoting public health: A review of empirical evidence. Sleep Medicine Reviews, 22, 23–36.

12. Klimas, N. G., Broderick, G., & Fletcher, M. A. (2012). Biomarkers for chronic fatigue. Brain, Behavior, and Immunity, 26(8), 1202–1210.

13. Office of Dietary Supplements. (2021a, March 26). Omega-3 fatty acids. National Institutes of Health. https://ods.od.nih.gov/factsheets/Omega3FattyAcidsHealthProfessional/

14. Office of Dietary Supplements. (2021b, March 26). Vitamin C. National Institutes of Health. https://ods.od.nih.gov/ factsheets/VitaminC-HealthProfessional/

15. Office of Dietary Supplements. (2021c, March 29). Magnesium. National Institutes of Health. https://ods.od.nih. gov/factsheets/Magnesium-HealthProfessional/

16. Office of Dietary Supplements. (2021d, March 30). Iron. National Institutes of Health. https://ods.od.nih.gov/ factsheets/Iron-HealthProfessional/

17. Outhoff, K. (2018). Magnesium: Effects on physical and mental performance. South African Family Practice, 60(4), 32–34.

18. Puetz, T. W., Flowers, S. S., & O’Connor, P. J. (2008). A randomized controlled trial of the effect of aerobic exercise training on feelings of energy and fatigue in sedentary young adults with persistent fatigue. Psychotherapy and Psychosomatics, 77(3), 167–174.

19. Rottoli, M., La Gioia, S., Frigeni, B., & Barcella, V. (2017). Pathophysiology, assessment, and management of multiple sclerosis fatigue: An update. Expert Review of Neurotherapeutics, 17(4), 373–379

20. Sood, B., & Keenaghan, M. (2021). Coenzyme Q10. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih. gov/books/NBK531491/

21. Stubhaug, B., Lier, H. O., Aßmus, J., Rongve, A., & Kvale, G. (2018). A 4-day mindfulness-based cognitive behavioral intervention program for CFS/ME. An open study with 1-year follow-up. Frontiers in Psychiatry/ Frontiers Research Foundation, 9, 720.

22. U.S. Department of Agriculture. (n.d.). FoodData Central. U.S. Department of Agriculture. https://fdc.nal.usda.gov/ fdc-app.html#/

23. World Health Organization. (n.d.). ICD-11 – Mortality and morbidity statistics. https://icd.who.int/browse11/l-m/en#/ http://id.who.int/icd/entity/1109546957

24. Yancey, J. R., & Thomas, S. M. (2012). Chronic fatigue syndrome: Diagnosis and treatment. American Family Physician, 86(8), 741-746