What Is Long COVID
Long COVID is a group of symptoms that persist or develop after an acute COVID-19 infection. It's also known as post-COVID syndrome or simply "long-haul COVID."
Long COVID is a lot more common than many people realize, and 10–20% of people who contract COVID-19 will go on to develop long COVID (World Health Organization [WHO], 2022).
Long COVID can look very different from person to person. Some people might experience mainly respiratory symptoms, others neurological, and others a combination. Sometimes the symptoms change over time. This is part of what makes it so difficult to understand and so easy to dismiss.
What Causes Long COVID
We don't know what causes long COVID. But researchers have identified several biological changes that seem to explain why symptoms last so long.
Mitochondrial Dysfunction
Mitochondria are the parts of your cells that produce energy, and COVID-19 can disrupt how they work. When your cells don’t make enough energy, this can affect the immune system, the brain, and the heart. Research in people recovering from severe COVID-19 suggests some of these changes may last beyond the initial illness (Yuan et al., 2025).
Immune Dysregulation
After infection, the immune system can stay overactive or become confused. In some cases, it starts attacking the body’s own tissues. This can affect the nervous system and the gut. As a result, symptoms can continue long after the virus is gone (Castanares-Zapatero et al., 2022). Some people also develop mast cell activation syndrome (MCAS), where immune cells release too much histamine and other chemicals, causing flushing, hives, gut symptoms, and a racing heart.
Viral Persistence
In some people, pieces of the virus may remain in the body, especially in the gut. In others, the infection may wake up dormant viruses like Epstein-Barr (EBV) or HHV-6. These reactivated viruses can contribute to fatigue and neurological symptoms (Castanares-Zapatero et al., 2022).
Microvascular Dysfunction
An emerging hypothesis suggests that tiny fibrinaloid microclots can form and block oxygen and nutrient delivery at the capillary level. This may help explain the wide range of symptoms seen in long COVID, especially those related to fatigue and brain function (Kell et al., 2024). While still preliminary, it offers a possible reason why therapies that improve tissue oxygenation, such as hyperbaric oxygen therapy (HBOT), can be helpful in some cases.
Autonomic Nervous System Dysregulation
COVID-19 can disrupt the autonomic nervous system, which controls functions like heart rate, blood pressure, and digestion. This dysfunction—known as dysautonomia—often shows up as Postural Orthostatic Tachycardia Syndrome (POTS), where the heart rate rises abnormally when standing. This can lead to symptoms like dizziness, palpitations, fatigue, and brain fog.
People with insulin resistance or obesity often have lower energy production at the cellular level. They may also have fewer antioxidants to deal with stress and inflammation. This can make it harder for the body to recover after an infection.
Who Is At Risk
Long COVID can affect anyone who has had COVID-19, but some people are more likely to develop it than others.
Older adults, women, and people with pre-existing conditions (especially metabolic disorders like type 2 diabetes, obesity, or cardiovascular disease) are at higher risk of long COVID. They usually experience more severe symptoms too.
Other things to consider include:
Lifestyle factors such as poor sleep and chronic stress
A diet high in ultra-processed foods
Poor gut health
Symptoms to Look For
Long COVID can look different from person to person. Your symptoms can be mild or severe and change over time. They can include:
Post-exertional malaise (PEM): a significant worsening of symptoms after physical or mental activity, which can last days
Trouble focusing and memory problems
Confusion
Shortness of breath
Headaches
Trouble sleeping
Heart palpitations
Muscle or joint pain
Anxiety
Long COVID symptoms can also look a lot like fibromyalgia or anxiety. This is why it's so hard to diagnose it. Long COVID symptoms also overlap heavily with chronic fatigue syndrome (ME/CFS); at six months and beyond, the two conditions are often clinically the same.
How Is Long COVID Diagnosed
There isn’t a lab test for long COVID. Blood tests and chest X-rays often look normal in people with long COVID, so that doesn't help either.
A doctor might diagnose long COVID after looking at your symptoms and medical history. If you're still having symptoms 12 weeks after a COVID infection or they can’t be explained by something else, you might have long COVID. Sometimes a clinic or team with experience in post-COVID care is the best choice.
How Is Long COVID Treated With Regenerative Therapies
Standard treatment for long COVID can include medication for mood, breathing exercises, or therapy for fatigue. These things can help, but they often don’t get to the root of the problem.
Regenerative and integrative medicine offer an alternative. Instead of dealing with symptoms in isolation, they address the underlying causes — low energy at the cell level, immune issues, gut problems, and ongoing inflammation — and try to support the body's capacity for recovery.
Treatments that may help include:
Hyperbaric Oxygen Therapy (HBOT)
HBOT has shown the most promising results among regenerative options so far. A randomized controlled trial found that HBOT improved quality of life, sleep, psychiatric symptoms, and pain in long COVID patients, with benefits persisting one year after treatment (Hadanny et al., 2024). Another RCT showed that it can improve brain blood flow and improve symptoms like fatigue, sleep, and pain (Zilberman-Itskovich et al., 2022).
Nutrition Support
Good nutrition is a big part of recovery. You can support your body with the right nutrients, including magnesium, omega-3s, and CoQ10. Cutting back on ultra-processed foods can also help lower inflammation.
Gut Health Support
Changes to diet and adding probiotics may help, since problems in the gut—like an imbalance in bacteria or a “leaky” gut lining—can keep the immune system out of balance.
Stem Cell Therapy
Early research in severe COVID-19 cases suggests that mesenchymal stem cell therapy may support recovery at the cellular level, including in lung tissue, although this area is still being studied (Yuan et al., 2025).
None of these approaches is a cure, and they work best as part of an integrated plan that includes conventional medical support and lifestyle changes.
Vagus Nerve Stimulation and Autonomic Retraining
For people whose long COVID shows up with dysautonomia or POTS, vagus nerve stimulation and breath-based autonomic retraining can help restore nervous system balance. These approaches are low-risk and increasingly used alongside other treatments.
A 2024 pilot study on 24 female long COVID patients showed that 10 days of transcutaneous vagus nerve stimulation (t-VNS; 30 minutes twice daily at home) significantly improved cognition, anxiety, depression, fatigue, and sleep quality, with benefits persisting at 1-month follow-up (Zhen et al., 2024).
What Are The Possible Complications
Long COVID can impact your quality of life and overall health, causing you to feel weak and tired all the time. Many people with long COVID experience day-to-day difficulties that make it hard to work or carry out tasks.
Some of the most serious long-term symptoms are neurological, including:
brain fog
memory problems
mood disturbance
Over time, avoiding physical activity because it makes symptoms worse can also weaken the body and make recovery more difficult.
Having long COVID can also make you more susceptible to developing conditions like arrhythmias, cognitive decline, and autoimmune disorders.
It can also raise the risk of experiencing mental health complications. Living with a condition that is poorly understood and that others may dismiss can be isolating and demoralizing. Addressing psychological well-being is an important part of long COVID care.
Can Long COVID Be Prevented
Prevention of long COVID starts with preventing COVID-19 infection. Getting vaccinated seems to reduce the risk of long COVID and the severity of acute infection.
Improving your overall health before and during an infection can also make a big difference. Things like keeping your blood sugar stable, staying active, and maintaining a healthy weight can support your body's energy and recovery.
If you contract COVID-19, you can minimize the risk of developing long COVID by:
pacing yourself during recovery
Not ignoring fatigue, returning to intense exercise too early, or pushing too hard can increase the risk of post-acute symptoms.
Simple things like rest, proper nutrition, good sleep, and stress management can help you recover faster.
Something important to keep in mind? Some people will develop long COVID no matter how careful they are because of genetic factors, a compromised immune system, and circumstances outside anyone's control. Prevention efforts are important, but they are not guarantees.
Takeaway
Long COVID affects millions of people, and there is no single treatment that works for everyone.
The most effective approaches look at it as a condition that affects multiple systems in the body. In many cases, identifying and treating symptoms can improve overall health and daily functioning.
If Long COVID is affecting your quality of life, look for a provider who takes your symptoms seriously. The right support can help in your recovery.
