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It has been more than a year since the COVID pandemic hit us with full force. It’s taken a toll on all of us, affecting our finances and health. Some of these effects are more forceful and some are more subtle, with consequences yet to unveil themselves in the months and years to come.
Whilst the social restrictions are lifting in many countries, for many people who have had the virus, life isn’t quite getting back to normal as they’re left with prolonged effects of the infection – the so called ‘Long COVID’, or ‘Post-acute COVID-19 syndrome’.
The scientific community has pulled together in a combined effort to understand the triggers and drivers of long-COVID symptoms, and although a lot is yet to be discovered and understood, hopefully this effort will yield additional research to aid the “long-haulers” in the near future.
Is Long COVID a new condition or an old acquaintance? We dig into the research to uncover what happens in the body during and after the infection to help us understand the underlying factors of some of the symptoms we see, and to guide us to nutritional and lifestyle interventions that may be beneficial.
Even though there isn’t a clear definition or diagnostic criteria so far, Long COVID has been defined as persistent symptoms and/or delayed or long-term complications beyond 4 weeks from the onset of acute COVID-19 symptoms.1,2,3
The largest systemic review and meta-analysis to date has identified more than 50 long-term effects associated with COVID-19.4 Amongst them, the most common ones include:4,5
Almost half the patients also notice a decline in their quality of life.5 In UK alone, an estimated 1.1 million (1 in 5 who tested positive) reported symptoms persisting more than four weeks after the first suspected infection.11
It is not uncommon to be left with post-acute infectious symptoms; it’s also been observed in Acute Respiratory Distress Syndrome (ARDS),12 Severe Acute Respiratory Syndrome (SARS), and Middle East Respiratory Syndrome (MERS).13
Why are some people left with post-viral symptoms? The clue is in how our body reacts to a virus. In response to an acute infection, the immune system mounts a powerful inflammatory response. This can leave us with inflammation, tissue damage,1 and the expected sequelae of post-critical illness.14 But of course, not everyone is affected. There seems to be an association between the risk of developing Long COVID symptoms and pre-existing conditions like respiratory disease, higher body mass index, older age and individuals from ethnic minorities. 15
Inflammation is a key tool in our immune system’s kit when fighting infections or repairing tissue after injury. It is essential to fight off a pathogen, but unfortunately sometimes it can go awry and cause further, often long-term problems. This is more likely to happen in predisposed individuals, being influenced by factors such as; genetic susceptibility, age, nutritional status, viral load exposure and route of infection, presence of other infections, pre-existing chronic diseases.4,15
It has been shown that many individuals still have a number of signs of the disease process well after the acute phase of the infection. Tests often show raised inflammatory markers; interleukin-6 (IL-6), serum ferritin, histamine, and C-reactive protein (CRP),4 and mitochondrial proteins and antioxidants [e.g. peroxiredoxin 3 (PRDX3) and carbamoyl phosphate synthase (CPS1)],16 alongside abnormal chest X-ray/computed tomography (CT).4
Ensure a nourishing anti-inflammatory diet, full of diverse, colourful, plant-rich foods, and ‘superfoods’ such as turmeric, ginger, green tea, and pomegranate. Also, supplementing with anti-inflammatory and antioxidant nutrients and botanicals to help you reach a more therapeutic dosage, would be ideal, particularly focusing on omega-3,17 curcumin,18,19 and quercetin.20,21,22
Increase the intake of antioxidants, such as vitamins C, E, selenium, beta carotene, glutathione 23 to help quench free radicals, reduce tissue damage, and improve energy levels. N-Acetyl Cysteine is also beneficial at replenishing glutathione stores.24
The majority of people mention fatigue as the main symptom.4 A UK based study showed that more women (54.3%) suffered with moderate or severe fatigue than men (29.6%).15
It often coincides with breathlessness (low oxygen levels), altered cognitive function, sleeping difficulties and psychological distress,25,13 and post-traumatic stress disorder (PTSD). 15
The elevations in mitochondrial proteins and antioxidants suggest ongoing mitochondrial 16 and tissue damage .26,27,28 As mitochondria are the key structures within your cells that produce energy, no wonder one of the leading symptoms of long-COVID is fatigue.
The prevalence of fatigue is in keeping with previous epidemics of SARS, H1N1, and Ebola, in which a large proportion of fatigued patients have qualified for a diagnosis of Myalgia Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). The symptoms observed in post-COVID-19 patients, resemble in part the CFS or ME, which are characterised by at least six months of fatigue and exhaustion, driven by similar factors like hormonal and nervous dysfunction, inflammation, compromised mitochondria, and oxidative stress.29
The first step of restoring mitochondrial health and improving energy levels is to provide plenty of antioxidants which we mentioned already. In addition, ensure a good intake of B vitamins, CoQ10, magnesium,30,31 Alpha Lipoic Acid (ALA),32 carnitine,32 and D-ribose 33 which are all involved in mitochondrial energy production.
The ongoing inflammation, as well as mitochondrial damage, can have a profound effect on our nervous system and brain function. Our brain uses up to 20% of all energy being produced, so if that vital function is compromised, we can see a decline in brain function which can impact us in many ways. Similar to chronic post-acute-SARS syndrome, long-COVID is also associated with depression, sleep disturbances,34 loss of sense of smell or taste,35 headaches and migraines,36 and an increased risk of stroke, intracranial haemorrhage,37 and dementia.8,37
These symptoms are linked to inflammation in the brain and the CSF (Cerebral Spinal Fluid), with high amounts of pro-inflammatory cytokines (e.g. IL-1beta, IFN-gamma,),38 cerebrovascular disease,39 low oxygen supply, side effects of medications, and the emotional aspect of having a serious illness.40 It’s also been hypothesised that the headaches can be caused by disrupted CSF drainage which might cause an increase in intracranial hypertension.41
Women with a history of psychiatric disease seem to be more affected by PTSD, depression, and anxiety,38,42 especially if they’ve spent a long time at hospital.
Beyond the virus itself, the impact of isolation, lack of social contact, and stress should not be underestimated.
Nourish your nervous system by eating a whole-food, non-processed diet with a wide variety of fruits and vegetables, and consider supplementing with a good methylated multinutrient, fish oils,43 and probiotics. Optimise your sleep and manage stress levels for additional support. Have a go at forest-bathing, as getting out in nature will have great benefits on your mental health and immune system.44 If diet and lifestyle interventions are not enough to manage your stress and anxiety, consider calming herbs such as lemon balm,45 theanine,46 and chamomile.47
The ongoing inflammation, intensive medical treatments, and the virus itself,15,10 48,49 can collectively lead to damage and fibrosis of the lung tissue, making the lungs less efficient at oxygenating the body.50 Hence, shortness of breath is another common post-infectious symptom.
Those needing ICU admission and respiratory support, or suffering with lung problems before the infection, higher age, higher BMI, and ethnic minorities are also more likely to experience breathlessness post-hospital discharge.15
The lung tissue contains a number of protective antioxidants including superoxide dismutase (SOD) and glutathione peroxidase.51 During an infection, their levels may become depleted, leading to oxidative stress and increasing the risk of complications. Individuals with pneumonia often have reduced antioxidant status and it has been suggested that antioxidant supplementation may be useful to reduce disease severity.52
N-acetyl cysteine (NAC) protects lung tissue from damage,53 and has been shown to improve symptoms and prevent recurrences of bronchitis.54 Selenium supplementation increasesglutathione peroxidase levels,55 and may reduce the severity of pneumonia.56 Deep, slow, nose breathing is an excellent way of simultaneously increasing blood oxygenation, improving sleep quality, and reducing anxiety and depression, which may help restore energy levels post-infection.57
COVID-19 sufferers have been shown to have altered gut microbiota with a higher abundance of opportunistic pathogens (including Streptococcus, Rothia, Veillonella and Actinomyces),58 Candida albicans, Candida auris and Aspergillus flavus,59 and a lower abundance of beneficial bacteria (e.g. Faecalibacterium prausnitzii).60 These alterations, can also disrupt the respiratory tract through the “gut-lung axis” mucosal immune system.61 Also, the virus may directly damage the intestinal mucosa and cause digestive symptoms, but further research is needed to confirm this possibility.62
Another concern for the gut microbiome is the long term effect of using larger amounts of detergents, household cleaning products, and hand sanitisers,63 which is linked to higher incidence of inflammatory conditions and inflammation.64,65
A great starting point to supporting your gut function and microbiome is increasing the levels of beneficial bacteria in your diet, either via foods such as sauerkraut, kimchi, kombucha or by using a well-researched, clinically effective, and stable probiotic supplement. Also increase soluble fibre such as green vegetables, onions, oats, and pulses, which will feed the bacteria, add bulk to the stool if you have diarrhoea, and promote toxin clearance.
Whilst the research is still ongoing, what’s already been uncovered bears a lot of similarities with other infections and chronic conditions such as Chronic Fatigue Syndrome. Everyone’s long-COVID symptoms are likely to be different, driven by their genetic predisposition, health status before the infection, nutrient deficiencies, and the treatment used during the infection.
Identifying the underlying drivers of lingering post-infection symptoms, and how they can go on to affect our physical and mental health, facilitates implementation of a tailored nutrition and lifestyle plan that can help individuals to feel better. This is more important than ever, given the emerging problem of ‘post-viral fatigue/ syndrome.’
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