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Do You Have Long COVID? What is Long COVID? Long COVID Symptoms How COVID Impairs the Brain COVID-19 and Vaccination Questions COVID-19 Vaccination Myths and Truths
Immune System Glitches - Part 1 Beyond the Immune System - Part 2 Mitochondria Dysfunction - Part 3 Brain Invasion - Part 4 How Covid-19 Alters Energy Metabolism How Stress Activates Long COVID
Ten Diet Tips to Help Heal Long COVID Heal Long COVID Brain with Physical Activity Melatonin May Help Treat Long COVID Olfactory Training for Smell Loss
What is Metabolic Syndrome How Diet Triggers Metabolic Syndrome How Inflammation Causes Disease How Inflammation Damages Your Brain How High Insulin Levels Lead to Metabolic Disorders Insulin's Role in Skeletal Muscle When Fat Cells Go Bad: Short Version When Fat Cells Go Bad: Long Version The Wonderful Shades of Fat Cells
How to Reduce Inflammation Part 1 How to Reduce Inflammation Part 2 Anti-inflammatory Super Foods Healthy Substitutes for Ultra-Processed Foods Elimination Diets 101 Astaxanthin Protects Brain and Reduces Pain
All About Protein How Much Protein Do You Need? Why You Need Protein Seniors Need More Protein Plant Proteins Protein Foods 101 All About Fat How to Add Fat to Your Diet Saturated Fats and Heart Health Fatty Acid Chart
Why We Feel Pain What Causes Chronic Pain Glial Cells and Pain How Opioids Trigger Chronic Pain Steps to Treat Chronic Pain Pain Management How Nature Heals How Music Benefits Your Brain and Body Healing With Art Healing With Laughter
Does Your Brain Need Healing How the Brain Heals Brain Regeneration Starter Kit Neurodiversity and Brain Boosting Train Your Brain Brain Boosters Part 1 Brain Boosters Part 2 Feed Your Brain Glia Cells Protect the Brain
How to Make an Action Plan How to Take Control of Your Life PTSD and cPTSD Is Post Traumatic Stress Disorder (PTSD) a Metabolic Disorder? Fight Depression Being Kind to Yourself is Healthy How to Stop Procrastinating Prevent Suicide How to Heal From Religious Trauma
Exercise Prevents Metabolic Syndrome Exercise Reduces Inflammation and Activates Brown Fat Exercise Prevents Fat Dysfunction What Causes Exercise Intolerance How to Beat Exercise Intolerance How to Motivate Yourself to Exercise
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About Us
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Do you Have Long COVID?

Do you feel tired and sick with unexplainable health problems after recovering from COVID-19? You likely have Long COVID.

This information also applies to people with other post viral fatigue syndromes like myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS).

*Mark's Story: Long COVID (LC) with exercise intolerance

The leaves were just beginning to turn golden and red as I hiked down the trail. Suddenly an energetic brown and white terrier bounded up to me and gifted me with a friendly tail wag. His owner Mark* and I greeted each other. I hadn't seen Mark since the pandemic begin. As he talked he told me about his bout with COVID-19 several months ago. As a young and extremely healthy adult in his early 30's, he was surprised that he had not bounced back yet.

"I used to do cross fit and now I can't even finish an easy hike in the woods," Mark told me. "I went to one intense class and was out of commission for a week. My muscles ache and I have no energy. I could barely move. The trainer just told me I needed to suck it up and push through the pain to get my body back in shape!"

His main symptoms were fatigue, exercise intolerance, and brain fog. He had also dropped some weight and was having a hard time gaining it back due to some digestive issues, a lack of appetite and a loss of smell. Mark had no energy or desire to grocery shop, cook or prepare food.

I could see it was hard on him to go from a extremely active and fit person to one struggling to walk the dog and think clearly. Worse, some people in his life didn't believe him since he 'didn't look sick'. That made me mad; you can't judge how sick someone is by how they look. I could clearly see that Mark had Long COVID.

Marks's trainer's recommendation to continue to try to do high intensity exercise was wrong and actually could be harmful. Does this story sound familiar to you? Click here for how to treat exercise intolerance.

People who develop COVID-19 can have long-term health effects from their infection. These symptoms can include a combination of new, returning and/or ongoing health problems that occur for more than 4 weeks after recovery from SARS-CoV-2, the virus that causes COVID-19.

Kamiak Butte

This condition is known as Long COVID, Long Haul COVID, Chronic COVID, Post COVID, Post-Acute Sequelae of COVID-19 (PASC)/Post-COVID Condition (PCC), Post-COVID-19 syndrome, Ongoing symptomatic COVID-19, and/or post-COVID conditions (PCC). I usually refer to it as Long COVID since it is short and easy to say. I sometimes wonder if some of these researchers are getting paid by the word when they name disorders!

Although it is more common for those with serious cases of COVID-19 to develop Long COVID, people with mild COVID-19 infections can develop long term health problems too. In addition, getting re-infected with COVID increases your chance of developing Long COVID (Bowe et al. 2022).

Are you tired of defending yourself? Tired oil on canvas by Rodin Belle.

Ramon Casas, Public domain, via Wikimedia Commons

Are you tired of defending yourself? Need facts for skeptical people who don't think Long COVID is real?

Here are the latest estimations for cases of Long COVID after acute COVID-19 infection (discussion and sources in Greenhalgh et al. 2024). Keep in mind that when we are talking about Long COVID a person with one symptom (say reduced smell) counts the same as a person with multiple symptoms:

People with one or more symptoms of Long COVID include:

✿ 50-80% of unvaccinated people who were hospitalized with COVID-19

✿ 10-35% of unvaccinated people who were not hospitalized while sick with COVID-19

✿ 8-12% of vaccinated people who developed COVID-19

The Center for Disease Control and Prevention reports that 7.5% of USA adults (20 million people) currently have Long COVID symptoms. Women and Hispanic adults are more likely to divulge Long COVID than men or other ethnic groups.

A higher percentage of people who were hospitalized develop COVID-19. However, since most sick people are not hospitalized; the majority of people who develop Long COVID had only a mild case of COVID-19!

Check out our pages on the potential causes of Long COVID: from immune issues to dysfunctional mitochondria, brain inflammation, and more.

If you have Long COVID or another post-viral fatigue syndrome, know you are not alone.

Currently, the global estimation is that around 1 in 3 people who had COVID now have Long COVID (Hou et al. 2025). In 2023, there were approximately 100 million people suffering from Long COVID (Perumal et al. 2023). Around 4 million working-age Americans are too sick with Long COVID to work. That is a loss of $230 billion in wages (around 1% of the U.S. GDP) assuming an average US wage of $1,106 per week. To compound issues, many Americans have employee sponsored health insurance, so no work means no health insurance!

Since there is currently no accepted agreement on what constitutes Long COVID, estimations of how many people have it can vary in different reports. Some believe the 1 in 5 figure may be underestimating the problem. Regardless of the exact number however, everyone agrees that Long COVID is a serious problem.

COVID-19 can infect multiple organ systems; there are over 200 symptoms reported in Long COVID. Often the problems occur in clusters. These symptoms can occur for months and years after the initial viral infection. There can also be relapses triggered by stress, physical or mental activity and exercise (Davis et al. 2021).

Do you have another post viral fatigue syndrome like myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)?

This information can help you as well! Symptoms of ME/CFS are similar to those of Long COVID. It is believed that ME/CFS may be caused by an initial infection just like Long Covid. Treatments for Long COVID are being used to help people with other chronic fatigue disorders.

Bee climbing by Susan Fluegel

Are you sick and tired of being sick and tired with Long COVID? We can help.

Do you want accurate information to combat Long COVID?

Are you tired of doctors saying it is all in your head or people promoting misinformation and hyperbole about so called miracle cures using horse wormers, extreme diets, and household cleaners? Or even the patronizing attitude of more conventional doctors telling you to lose weight and exercise?

Boston Public Library, Public domain, via Wikimedia Commons

At the Metabolic Toolbox we summarize advice the best available research to help you get better. This website is written by me, Susan, and my very knowledgeable friend Lori. We are both nutritional professionals who have spent years helping people with metabolic disorders gain more energy and reclaim their health. We know all about metabolic disorders and have read and analyzed hundreds of research papers on this topic.

We are not funded by any drug or nutrient companies so you know you are getting our scientific opinion on what works. We aren't selling supplements, metabolic test profiles, or COVID-AWAY spray. All we are peddling is good, common sense information gleaned from the latest and best research on how to promote good health. We give you the information and YOU decide which techniques to try. In addition, we let you know WHY you are experiencing these symptoms. Both of us are open minded people who are willing to look at all treatment options from conventional to more alternative.

We cite our sources, so if you want, you can take a look at the original research articles and make up your own mind. Or send them to your doctor or a skeptical relative who doesn't understand why you aren't all better yet! Better still, send anyone who doubts that you have Long COVID here to this website to read about it.

I'm not going to sugar coat it; Long COVID is a complex disorder involving multiple physiological systems. It will take a while to get better. But with this knowledge you can begin your climb back to health.

Don't give up.

You do not have to be ashamed because you have Long COVID. You can get better.

Many people with Long COVID experience stigma (Pantelic et al. 2022, Clutterbuck et al. 2024). Because Long COVID is hard to understand, other people, coworkers or even medical professionals may not understand or believe that you have Long COVID.

We know it is exhausting to consistently have to advocate and speak up for yourself so let us do it for you. Send doubters a link to The Metabolic Toolbox while you block their number and relax. If you need an excuse, remember that stress may aggravate your Long COVID.

Remember that any virus infection, not just COVID-19, can cause long term symptoms such as Myalgic Encephalomyelitis (ME) and Chronic Fatigue Syndrome (CFS).

It will take time but you can recover from Long COVID or other secondary responses from viral infections. In many cases, time alone has allowed people to heal. If you have a severe reaction to activity and/or exercise, learning to listen to your body is important. See more about this in how to overcome exercise resistance.

*Names and some minor identifying details in all stories in this website are changed to protect people's privacy

I'm not your doctor so this is not medical information. I'm just a person who would like to see you happy and healthy. If you have any questions or concerns about Long COVID please consult a professional.

References:

Al-Najjar MAA, Al-Alwany RR, Al-Rshoud FM, Abu-Farha RK, Zawiah M. Menstrual changes following COVID-19 infection: A cross-sectional study from Jordan and Iraq. PLoS One. 2022 Jun 29;17(6):e0270537. doi: 10.1371/journal.pone.0270537. Full article.

Bowe B, Xie Y, Al-Aly Z. Acute and postacute sequelae associated with SARS-CoV-2 reinfection. Nat Med. 2022 Nov;28(11):2398-2405. doi: 10.1038/s41591-022-02051-3. Epub 2022 Nov 10. Full article.

Clutterbuck D, Ramasawmy M, Pantelic M, Hayer J, Begum F, Faghy M, Nasir N, Causer B, Heightman M, Allsopp G, Wootton D, Khan MA, Hastie C, Jackson M, Rayner C, Brown D, Parrett E, Jones G, Clarke R, Mcfarland S, Gabbay M, Banerjee A, Alwan NA; STIMULATE-ICP Consortium. Barriers to healthcare access and experiences of stigma: Findings from a coproduced Long Covid case-finding study. Health Expect. 2024 Apr;27(2):e14037. doi: 10.1111/hex.14037. Full article.

Coleman B, Casiraghi E, Blau H, Chan L, Haendel MA, Laraway B, Callahan TJ, Deer RR, Wilkins KJ, Reese J, Robinson PN. Risk of new-onset psychiatric sequelae of COVID-19 in the early and late post-acute phase. World Psychiatry. 2022 Jun;21(2):319-320. doi: 10.1002/wps.20992. Full article.

Davis HE, Assaf GS, McCorkell L, Wei H, Low RJ, Re'em Y, Redfield S, Austin JP, Akrami A. Characterizing long COVID in an international cohort: 7 months of symptoms and their impact. EClinicalMedicine. 2021 Aug;38:101019. doi: 10.1016/j.eclinm.2021.101019. Full article.

Durstenfeld MS, Peluso MJ, Peyser ND, Lin F, Knight SJ, Djibo A, Khatib R, Kitzman H, O'Brien E, Williams N, Isasi C, Kornak J, Carton TW, Olgin JE, Pletcher MJ, Marcus GM, Beatty AL. Factors Associated With Long COVID Symptoms in an Online Cohort Study. Open Forum Infect Dis. 2023 Feb 1;10(2):ofad047. doi: 10.1093/ofid/ofad047. Full article.

Greenhalgh T, Manoj Sivan, Alice Perlowski, Janko Nikolich. Long COVID: a clinical update. The Lancet, 2024; doi: 10.1016/S0140-6736(24)01136-X. Full article.

Hou Y, Gu T, Ni Z, Shi X, Ranney ML, Mukherjee B. Global Prevalence of Long COVID, Its Subtypes, and Risk Factors: An Updated Systematic Review and Meta-analysis. Open Forum Infect Dis. 2025 Aug 30;12(9):ofaf533. doi: 10.1093/ofid/ofaf533. Full article.

Kedor C, Freitag H, Meyer-Arndt L, Wittke K, Hanitsch LG, Zoller T, Steinbeis F, Haffke M, Rudolf G, Heidecker B, Bobbert T, Spranger J, Volk HD, Skurk C, Konietschke F, Paul F, Behrends U, Bellmann-Strobl J, Scheibenbogen C. A prospective observational study of post-COVID-19 chronic fatigue syndrome following the first pandemic wave in Germany and biomarkers associated with symptom severity. Nat Commun. 2022 Aug 30;13(1):5104. doi: 10.1038/s41467-022-32507-6. Erratum in: Nat Commun. 2022 Oct 12;13(1):6009. Full article.

Lebar V, Lagan AS, Chiantera V, Kunic T, Lukanovic D. The Effect of COVID-19 on the Menstrual Cycle: A Systematic Review. J Clin Med. 2022 Jun 30;11(13):3800. doi: 10.3390/jcm11133800. Full article.

Lee MH, Perl DP, Steiner J, Pasternack N, Li W, Maric D, Safavi F, Horkayne-Szakaly I, Jones R, Stram MN, Moncur JT, Hefti M, Folkerth RD, Nath A. Neurovascular injury with complement activation and inflammation in COVID-19. Brain. 2022 Jul 29;145(7):2555-2568. doi: 10.1093/brain/awac151. Full article.

Lee MH, Perl DP, Nair G, Li W, Maric D, Murray H, Dodd SJ, Koretsky AP, Watts JA, Cheung V, Masliah E, Horkayne-Szakaly I, Jones R, Stram MN, Moncur J, Hefti M, Folkerth RD, Nath A. Microvascular Injury in the Brains of Patients with Covid-19. N Engl J Med. 2021 Feb 4;384(5):481-483. doi: 10.1056/NEJMc2033369. Full article.

Lopez-Leon S, Wegman-Ostrosky T, Perelman C, Sepulveda R, Rebolledo PA, Cuapio A, Villapol S. More than 50 long-term effects of COVID-19: a systematic review and meta-analysis. Sci Rep. 2021 Aug 9;11(1):16144. doi: 10.1038/s41598-021-95565-8. Full article.

Moldofsky H, Patcai J. Chronic widespread musculoskeletal pain, fatigue, depression and disordered sleep in chronic post-SARS syndrome; a case-controlled study. BMC Neurol. 2011 Mar 24;11:37. doi: 10.1186/1471-2377-11-37. Full article.

Nalbandian A, Sehgal K, Gupta A, Madhavan MV, McGroder C, Stevens JS, Cook JR, Nordvig AS, Shalev D, Sehrawat TS, Ahluwalia N, Bikdeli B, Dietz D, Der-Nigoghossian C, Liyanage-Don N, Rosner GF, Bernstein EJ, Mohan S, Beckley AA, Seres DS, Choueiri TK, Uriel N, Ausiello JC, Accili D, Freedberg DE, Baldwin M, Schwartz A, Brodie D, Garcia CK, Elkind MSV, Connors JM, Bilezikian JP, Landry DW, Wan EY. Post-acute COVID-19 syndrome. Nat Med. 2021 Apr;27(4):601-615. doi: 10.1038/s41591-021-01283-z. Full article.

Pantelic M, Ziauddeen N, Boyes M, O'Hara ME, Hastie C, Alwan NA. Long Covid stigma: Estimating burden and validating scale in a UK-based sample. PLoS One. 2022 Nov 23;17(11):e0277317. doi: 10.1371/journal.pone.0277317. Full article.

Perlis RH, Santillana M, Ognyanova K, Safarpour A, Lunz Trujillo K, Simonson MD, Green J, Quintana A, Druckman J, Baum MA, Lazer D. Prevalence and Correlates of Long COVID Symptoms Among US Adults. JAMA Netw Open. 2022 Oct 3;5(10):e2238804. doi: 10.1001/jamanetworkopen.2022.38804. Full article.

Perumal R, Shunmugam L, Naidoo K, Abdool Karim SS, Wilkins D, Garzino-Demo A, Brechot C, Parthasarathy S, Vahlne A, Nikolich J. Long COVID: a review and proposed visualization of the complexity of long COVID. Front Immunol. 2023 Apr 20;14:1117464. doi: 10.3389/fimmu.2023.1117464. Full article.

Puntmann VO, Carerj ML, Wieters I, Fahim M, Arendt C, Hoffmann J, Shchendrygina A, Escher F, Vasa-Nicotera M, Zeiher AM, Vehreschild M, Nagel E. Outcomes of Cardiovascular Magnetic Resonance Imaging in Patients Recently Recovered From Coronavirus Disease 2019 (COVID-19). JAMA Cardiol. 2020 Nov 1;5(11):1265-1273. doi: 10.1001/jamacardio.2020.3557. Erratum in: JAMA Cardiol. 2020 Nov 1;5(11):1308. Full article.

Sharp GC, Fraser A, Sawyer G, Kountourides G, Easey KE, Ford G, Olszewska Z, Howe LD, Lawlor DA, Alvergne A, Maybin JA. The COVID-19 pandemic and the menstrual cycle: research gaps and opportunities. Int J Epidemiol. 2022 Jun 13;51(3):691-700. doi: 10.1093/ije/dyab239. Full article.

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Umesh A, Pranay K, Pandey RC, Gupta MK. Evidence mapping and review of long-COVID and its underlying pathophysiological mechanism. Infection. 2022 Oct;50(5):1053-1066. doi: 10.1007/s15010-022-01835-6. Full article.