top of page

Covid-19 Long Tail. What is it, and what can be done about it?

Hi everyone, 

I hope you are all well and have found a way to settle into this new “normal” we are all in. 

There’s going to be many changes to come. It will feel strange being close to other people again, and who knows how long we will have to queue just to nip into the shops and have to arrange to meet our friends outside. Some people are very happy to see pubs and restaurants reopen, others are very concerned. 

What about the aftermath and physical impacts of the virus on those who caught it? There has been a lot of discussion on the news about the so-called ‘long-tail’ of the COVID19 virus. It is estimated that around 1 in 10 people have a long, often painful and unrelenting recovery.  The long-term symptoms are often strange and unpredictable, with a mix of reports ranging from bursts of flu-like symptoms, fatigue, headaches, dizziness, upset stomach, to re-emergence of historical pain / symptoms (some people reporting that pain from childhood accidents have resurfaced after many years). The impacts of this virus also seems to be causing flare-ups in autoimmune conditions and even triggering autoimmunity for the first time. 

At Julia Davies Nutrition we are beginning to see clients come to us with these long-tail symptoms, so we’re working hard to understand what is going on as best we can. What is very clear is that each person requires different support and an individual approach.

I know this all sounds scary. And it is. It is all new to us and there is still so much we don’t know about the virus. But there is information that we do know, and every scientist in the world is working overtime to try and understand it more.

So what are our current thoughts? 

Firstly, it is likely that the long-tail effects are due to the disruption of the virus on the immune system and body, rather than the virus still being active. Presentations such as fatigue and headaches are possibly due to the body working hard to fight and clear the virus and therefore leaving the individual with reduced mitochondrial function (mitochondria is the energy producing part of every cell in the body). This can be supported through specific nutrients, or if there has been stomach upsets as a result of the virus it could mean that the digestive mechanisms are not functioning as efficiently as they should be and therefore key nutrients for mitochondrial health are not being absorbed. This can be rectified.

The inflammatory impacts such as resurgence of previous pain or autoimmune flare ups still remain a mystery. It is likely to be due to the huge demand on the immune system that the virus has caused. An individual may have been in remission from pain or autoimmunity due to working really hard to calm down inflammation but getting a virus (not just COVID) causes a spike in immune activity and a big process takes place and this causes a disruption to the whole body. 

The effects of this virus are due to the individual’s immune response that was triggered by the virus. We have a bank of antioxidants that are stored for this exact situation. So replacing these antioxidants through diet and supplementation is a great way to start. It is also something fundamental to keep in mind for the purposes of prevention. However the virus impacts the individual - whether that’s a nasty flare of IBS or continued fatigue - we do know that this is due to an inflammatory response, so calming inflammation on every level is absolutely key. You can do this in several ways: 

  1. Removing inflammatory foods (processed foods, sugar, gluten, dairy)

  2. Focusing on wholefoods (foods in their whole form; fruit and vegetables, pulses, beans, good quality meat and fish)

  3. Replenishing key immune nutrients (getting Vitamin D tested, addressing specific immune nutrients such as glutathione, selenium, zinc)

  4. The nervous system and immune system are intimately linked. Focusing on relaxation and reducing any stress is fundamental. 

  5. Sleep hygiene. Many repair processes take place when we sleep, so getting proper sleep post-illness is very important. To improve sleep quality you can stop looking at screens 2 hrs before sleep, wind down with a book, try meditation.

Gut health

When we think about the immune system we must always expand that to thinking about the gut. Over 70% of our immune system is located in the gut and our gut health and ecosystem of microbiome have a crucial role to play in overall inflammation and immune activity. Disruptions to the gut (gastritis, food sensitivities, poor digestion, overgrowth of bacteria or presence of pathogens) can have a major impact on the immune system. Optimising gut health is integral for pretty much everything in the body, but particularly when recovering from illness. Here is a quote from a recent study by El Omar et al (May 2020):

It may be possible to look in the gut for a solution to or mitigation of [COVID-19] infection. The ecosystem of the gut and commensal microbiota can both regulate and be regulated by invading viruses, facilitating either stimulatory or suppressive effects. Therefore, it is plausible to consider whether the gut and [COVID-19] may play significant roles in the intensity of the infection and its clinical outcomes.

Anyone who has worked with us at the clinic will be familiar with the concept of understanding your own unique environment within your gut. Your ecosystem. It’s arguably the most important part of our entire health. We have our own terrain which either encourages or discourages harmful pathogens to take residence and cause problems. Many COVID survivors are experiencing nasty ongoing IBS type symptoms and while the reason for this still remains unclear - and there are some scientists that believe the virus could still be active - if there is ongoing diarrhoea, I think that in the more long term cases that it is more likely to be a post-viral symptom which is a result of the disruption the virus has caused to the ecosystem of the gut while it was passing through when the body was clearing it. The picture we are left with is known as ‘dysbiosis’ which basically means an unbalanced microbiome community. And this can be corrected. Here are some ways to improve gut health:

  • Eat plenty of fibre, aka Prebiotics (root vegetables, legumes, wholegrains, onion, leeks, garlic, asparagus)

  • Eating a rainbow of colours in the form of fruit and vegetables (aiming for as many different colours every day will ensure your body gets an abundance of vital polyphenols)

  • Eat slowly, aiming for 25-30 chews per mouthful

  • Taking apple cider vinegar in a little warm water 15 minutes before a meal can really improve digestion

  • Eating probiotic foods such as sauerkraut, kimchi, kefir, miso, kombucha 

  • Avoiding sugar, processed foods, gluten and dairy products

So there’s lots to consider here and I hope this newsletter isn’t too dense! To lighten up, here are a few recommendations for things I have been enjoying lately during lockdown: 

  • Cooking Your Way Through the Pandemic - a very sweet and funny account of busy family life by Stanley Tucci which no doubt many of you can relate to

  • Glastonbury highlights over the years - streaming on iplayer (David Bowie’s was particularly magical) 

  • Louis Theroux has started a new lockdown podcast - check out his catch up with Lenny Henry and Miriam Margolyes 

  • A recording of Wise Children by Angela Carter is available on iplayer.

Please let us know how you have been getting on or if you are experiencing any post-viral symptoms. And feel free to share this with anyone who may find it helpful. 

Best wishes,


If you suspect you have Covid-19 and are displaying symptoms such as high temperature, a new, continuous cough and a loss or change to your sense of smell or taste, contact your primary care provider immediately.

Book an appointment today by visiting


Recent Posts

See All


bottom of page