In Conversation With

Dr Denef Talks About Her Recovery from Long-COVID


Dr. Denef knew something was wrong when her COVID symptoms were persisting, but this was before 'Long-COVID' was recognised and accepted as a significant and urgent public health problem. 

Luckily, her medical training, determination and the experience of overcoming health challenges with her son helped her on a journey to recovery. In this inspiring interview we hear about Dr Denef's story, the common links she found with Long-COVID and her patients with Lymes and Chronic Fatigue. 

We hear about what helped the most in reducing her symptoms, including how important she found Nurosym in her recovery. We they hear how she now approaches helping her patients suffering form Long-COVID. 


Dr. Liesbeth Denef


Inflamed Bodies, Depressed Minds - Ed Bullmore (20 min read)

The Inflamed Mind: A Radical New Approach to Depression (book)

Dr. Liesbeth Denef Official Website 

Dr Liesbeth Denef Teaching Platform (Long Covid Webinars)

Access the Nurosym Device 

The key to Long-Covid: Mechanisms and Potential Treatments - Dr Burchi

Dr David Strain and Long-COVID Treatment - Interview 




Thank you for joining us.

So today we have Dr. Liesbeth Denef, joining us from Belgium. And we're excited to have her on the call today.

Dr. Denef is a General Practitioner from Belgium, specialising in functional medicine. And this looks at a more cohesive view of the patient beyond just a symptomatic level, looking at kind of a multifactorial level of the individual to target someone's health and improve their health.

So there's a few reasons why we're speaking to Dr. Denef today, one because of her journey with long COVID. And particularly using the Nurosym in long COVID.

But also for the work that she has been doing in this area on educating as well. So perhaps you could actually give a bit of a background on yourself as well, that will help our listeners today.


Dr Denef 

Okay, so Hello, thank you for having me in this call.

Well, it was it was kind of a long journey because like 12 years ago, I was still living in Switzerland in Geneva, my son when he was born got very sick.

His immune system crumbled completely. In a very short period of time, he was like two years old. So back then, nobody was talking about the gut brain link. Absolutely nobody.

So I very quickly found out that when he didn't eat because he got hospitalised for intestinal flu, he didn't eat and came back to normal completely. So I found my child back. And I was like, my God is coming from the gut.

So I started my research back then everybody said I was crazy, because I come from a very Cartesian scientific family. And nobody heard about the gut brain link back then it was like 14 years ago.

So I was studying a lot about what mums were seeing in the States, because there they were already into that, the microbiome and all of that. And so I studied that at night for like three years, and I got him out of there.

So now he's perfectly fine. So that was how I discovered this whole link between the gut and the brain and behaviour.And so that's how I learned about food sensitivities, and about inflammation, all of that. And then I did a couple of trainings in Europe in integrative medicine and naturopathic medicine, or to Molecular Medicine, a lot of personal development, because it was very, very hard my own health went down the drain, because it was a very stressful period.

And in Switzerland, I had the chance to take an hour probation because the system is very different over there. So a little by little, I started looking at all the factors of people's lives.

And so yeah, that's the way it evolved. And so now, I have my Centre in Brussels where, me, myself, I work that way. I have two health coaches who are the same way because they all went through their own health struggles with long COVID.

And so yeah, it's always best when you go yourself through these kind of things. Because in medical school, we don't really learn functional medicine. It's very, and I'm not against it at all, because that's what I see.

These are the patients that are left out of the traditional field because their problems are chronic. And they're very vague and there is no reductionist view possible on these kinds of problems, you have to look at the total picture because everything is linked to each other.

And so yeah in my centre we have hydrotherapy and we have psychotherapists so yeah we have we offer a very global, how do you say this, taking charge of patients?


That's great.

So this must have been very interesting for yourself then, so when you then contracted the Coronavirus, you then have this kind of different approach to most people.

You had this experience, obviously the traditional medical experience, but then this additional side of the experience with your son and then the evolution and learning into this space.

That must have given you an insight into okay well then how this is unfolding over yourself, and then you obviously then contracted long COVID. Perhaps you can tell us a bit about your journey initially getting Coronavirus, and then how those symptoms persisted for you.


Dr Denef 

Yeah, it was the most horrible experience you can ever imagine for me. I got it very mildly in March a year ago, but I was in very stressful period on an emotional level as well which of course doesn't doesn't help.

Then two months later it felt like I got it again, but of course nobody was talking about long COVID back then so I didn't understand what's happening. It was like, did I get it again, because I got all the symptoms back, the coughing, I wasn't feeling well.

And then suddenly, a couple of days later I got this attack, I got something that felt like a panic attack, like a surge coming out. I couldn't see anymore. I was getting dizzy, I fell on the floor. I couldn't breathe and I was like, what is happening?

I've never had a panic attack in my life. So I didn't understand it at all. And so I tried to breathe in a bag, I tried to take a benzodiazepine that I had there, it wasn't helping.

So I had to call the ambulance, they came. They didn't get it, they gave me valium. They give me diazepam. It calmed down very slowly over a couple of hours. And then the next day I ate, and it started again.

It was like what is this, I was like, I'm having an allergic reaction. So I took Zyrtec, I took an antihistamine, and immediately it went away.

And I was like, what is this, because of course I already had from the past, I already had food sensitivities and gluten intolerance, but I never reacted in an allergic way. I had itches. I had hives everywhere.

And then I was lucky enough to have my best friend who is an immunologist who just came back from a seminar in London about mast cell activation. She said, I think you have mast cell activation. I was like what?

We never even learned about that in medicine. Because it's a very new diagnosis. I mean, it's very tricky because there's no real diagnostic. There's not an easy diagnosis of this.

And so I started reading about that I was like, oh my God, this looks horrible. And indeed, I could not eat anything anymore, or I will almost get an anaphylactic shock.

So I lost 10 kilos, I was having my eyes swollen it was it was just horrible. And then I started taking mast cell stabilisers, ketotifen, which really, really helped. I started on a low histamine diet. I took anti histamines, but I had a very high dose of ketotifen like 12 milligrammes a day.

I was living on like chicken, broccoli and sweet potatoes. You know. I was just like, not eating anything. So that took the edge off. Because you know, I'm a single mom I had to paint my own building, I couldn't stop working. Nobody wants to give me... the doctors were not even believing me... because long COVID back then was not something that was known of, you know.

So I was in a situation where a lot of my patients, when they have chronic disease for example. Lyme is very similar and nobody believes you know. I was like, oh my god, this is what people go through when they're not recognised, you know, by traditional medicine.

Because I learned that long COVID is a vascular disease as well, where the endothelium is attacked. Yeah. And so with the EWOT, you get into angiogenesis. So you're going to create new blood vessels. So that helped me a lot.

But I had to be very careful, because the smallest physical exercise would push me to relapse, the day after. And then I found the Facebook group about long COVID.

And then I was seeing all these people having the same ups and downs that I've had, and that I've had for a whole year. I've had relapse after relapse after relapse after relapse, because I didn't have these very bad allergic reactions anymore.

But I had the feeling that the level of inflammation in my body was very high. So my baseline of inflammation was very high. So every other small virus that came by, I would get back into this COVID response.

And that's what I see in the groups, is that people always talk about the COVID relapse.

So the whole thing is to try to get the inflammation down. And that's extremely difficult because you don't have the time because your immune system is activated, like once every two weeks, you have a virus.

So bam, bam, you're always going back in that inflammation, your muscles get triggered again, you start releasing histamine again.

You're in this vicious circle]being in this inflammatory state, and then reacting at every virus that comes by and you just can't put it down.

And what helped as well a lot, and that's when I knew that my vagus [was underactive], because I had severe POTS, severe POTS, I could not stand on my legs for more than two minutes.

I would have to pee all the time. I couldn't swallow. So all my autonomic nervous system functions are just gone. And that's when I started to do the breathing, the Wim Hof breathing, and ice bath. So I did a whole winter of freaking cold ice baths.



That's great, I'm a big ice bath fan as well.

Just quickly, for people who don't necessarily know what POTS is; postural orthostatic tachycardia syndrome, which is the essentially dysfunction of the autonomic nervous system.


Dr Denef 

Yeah. Where you're essentially... your blood pressure suddenly drops here or your heart rate suddenly goes up and you have all these symptoms where you have difficulty swallowing, you have to pee all the time you feel weak.

So the ice baths... and then it was like, oh my God, this is stimulating my vagus [nerve].

And it's very funny, because intuitively, I started singing in the morning. So I sometimes did an hour of mantra singing and it helped me so much. Yeah. And it was like of course, the singing is stimulating my vagus [nerve].

And then I started researching about the vagus nerve. And then... because all of this in medical school, we don't really get to know the importance of the vagus nerve. Yes, we know about it. But yeah, not on that level.

And so then by accident, I fell on study that you did in the University of Brussels, with the device, but I already had a device like that five years ago, but it was not a good device.

So I let go of it. And then I found your device. And I, I saw the results. And I was like wow, this is amazing.

So I bought it. And immediately within a week of using it, I felt inflammation going down. Much better mood, it was mostly on the mood that it was incredible.

Because I felt very depressed, I felt very.. it was amazing, I didn't want to see people anymore. With me, I was a very social person. I was completely isolated, completely in myself, couldn't take the phone to talk to people.

And since the Parasym, since the Nurosym, sorry. I feel like going out again. I feel like seeing people again. And when I feel anxious, and I put it on, immediately, I feel my stress levels go down. So I'm very excited about this.



That's great. It's like a tap right into the parasympathetic nervous system.


Dr Denef 

Yes, yes. So that's, I don't know if it was too long or too short.



That's fantastic.

Thanks so much for that overview. That's really helpful.

And obviously, we're very glad as well that you've had such a great response there. So yeah, you just touched on our research. Perhaps I'll just talk a little bit about that, because that might be interesting for some of our listeners as well.

So I guess our journey in this area. So as a company, we're called Parasym. Our product, Nurosym, is for essentially, non-invasive vagus nerve stimulation. And you mentioned the effects in depression.

So, vagus nerve stimulation as an area has been around for decades now, actually, but its traditionally implanted vagus nerve stimulation. So you surgically implant an electrode that goes around the vagus nerve with a pacemaker style device that will then stimulate.

Obviously, it's surgery, there's risks involved with implantation, it's also expensive, it's not offered to everyone. Often the most severe people will end up getting it because of the risks involved. And so it leaves a lot of people either unable to access it, or not severe enough to be able to get it, or cost prohibitive as well.

The reason why we got into this area is we wanted to help all those people that we thought can benefit from this technology, if we can find a way to deliver it non invasively.

So fast forward six years, and we developed a non invasive device that everyone hopefully has been waiting for. We've got several randomised placebo controlled trials backing our technology, we've got a specific, proprietary method of simulation delivery that is proven to be now safe and effective.

We've actually conducted the first clinical trial into long COVID with this technology. And that was done at a partner clinic in Belgium. It was a small pilot study, but it had very encouraging results.

Everyone improved in that study, which was great.

And since the study has been completed, that clinic has now treated over 100, long COVID patients with all similar results to that study.

So very exciting area, we're now extending this research to a partner centre, specialising in autonomic dysfunction in London, a world renowned centre there.

That study hasn't been announced yet. But that will be a controlled, placebo controlled, randomised, larger scale study that will support the use of this device for long COVID as well.

So yeah, we're very excited about this area. And we're continuing to research into it. And not only that, we're expanding our research into a lot of other areas as well, because this area, that is termed neuromodulation, which is essentially modulating the brain and the nervous system using micro pulses electrical current, has application to a lot of different [conditions].

So you mentioned depression, autoimmune diseases. And actually say depression, the theorised mechanisms of action depression, one of which is modulating neurotransmitters in the brain.

But there's also a new school of thought around the potential anti inflammatory mechanisms contributing to this benefit of reduced depressive symptoms as well.

So, for anyone interested in looking, it's potentially useful to look at Ed Bullmore's work, we'll leave a link to that as well. He has a lot of work is done around the inflamed mind ['Inflamed Depression'].

And it's estimated that at least 30% of people with major depressive disorder have significantly elevated inflammatory cytokines in their system.

Those cytokines will be circulating around going to brain and when they're in the brain, that's when they can have this effect, of the whole host of depressive symptoms, that you get with that.

So from that level, it makes sense, the dots are still being connected there, there's been kind of lack of the mechanistic studies translating into into that area. But the evidence to date is still quite compelling.

But also, as I think interestingly, the way this space evolves is with the controlled studies showing the effects and then sometimes looking back and saying- Okay, well, these are the mechanisms.. and we're still starting to understand some of the mechanisms here.

Potentially that's interesting for us to then quickly talk about long COVID. So one of our team has written a piece, which I'll also link to, about the currently theorised mechanisms for long COVID.

And interesting as well, you mentioned, these kind of waves that yourself and people in, other people suffering from long COVID in the support groups have been going through.

So one of the theorised mechanisms is a residual of the virus in different parts of the body that then can still persist and relocate at different times. And then there's also the And the autonomic dysfunction element, which is the thesis which were, we're looking at quite a lot as well and with our partners in London.

Part of that is theorised around a... you mentioned the endothelial as well, infection of the endothelial cells, and potentially the brainstem as well. And those are well known to trigger and cause autonomic dysfunction.

So, based on a different area of research that we've been working on for several years already, around cardiovascular health and cardiovascular disease. And we've shown already in controlled studies, improvement in endothelial function, after the use of our device as well.


Dr Denef 




That's kind of an interesting learning that we're connecting the dots backwards, that we've seen this impact in endothelial function, after contracting Coronavirus, and when people have long COVID.

And then we've seen in this other aspect of our research, people who already have poor endothelial function and cardiovascular disease, had a benefit there.

So, and then, with our technology, stimulating the pathway that we do, can have this parasympathetic activation, rebalancing the autonomic nervous system and decreasing inflammation.

Those mechanisms there, then targeting the mechanisms that are thought to trigger long COVID.

So I think, it's also important to say that there's not necessarily one type of long COVID, there's likely many different types of long COVID.

And, as is covered in our article written by one of our team, you know, it could be someone who has had acute damage, or damage to specific organs or parts of their body from the acute infection; and their symptoms that are persisting are down to that, and are not necessarily down to the mechanisms that I've just mentioned.

There's also other hypothesised mechanisms that are contributing to long COVID. But again, I think what we've kind of worked on is okay, looked at the evidence to date looked at those mechanisms.

We thought that we can have a benefit here, we've then worked on a study, we've seen that there is that benefit in those patients, quite a significant benefit. And then we decided to then take that over to pursue the research in a larger control study.

So yeah, and I think, the way this space usually works, again, because long COVID is new, but there's been this extension of all these other people with similar conditions that you kind of mentioned before, say chronic fatigue.


Dr Denef 




So it's, it's kind of an extension of this area.

So we kind of want to take that and, contribute as much as we can to the research in the field.


Dr Denef 

It's amazing.

Dr Denef 

And, and I put everybody on the Nurosym, and I'm seeing amazing results. This is really showing me something I didn't know. You know.


That's fantastic. That's great to hear.

So I think it will be really useful to know, potentially, for some listeners as well, to learn a bit more about your practice. So the OVIVE Medical Centre.

So part of the reason why we're doing this series of 'Nurosym in conversations with', is to spread the education on the research in this area, personal stories, such as yourself.

But then also to share the awareness of really valuable clinics such as yours, and what important work you're doing.

So essentially, you can talk a bit about... because I know that you're also running webinars soon, kind of covering these key, really important topics in more detail.

Dr Denef 

Well, I'm on the verge of setting it all up.

Because I was like, I can't start doing all of this, when, me myself, I'm still feeling sick. And I have these waves, that I don't know if I will be able to... on the day of the webinar not have a relapse.

Now that I have the Nurosym, I've been feeling much better. So I feel like ready to help other people.

Of course, I'm not University clinic. So me, I'm in functional medicine, which is like different, it's more like - avant garde. I'm following all the research that is done in the states in functional medicine.

So I've been listening a lot of what is happening there. And so what I'm going to do, of course, my website is in French, so if people want to sign up, the best is that they just go on my website, which you will put in the link.

And then they send an email to my office, because I haven't put the dates yet for the long COVID webinars. But I'm going to do them in English.

So for people that are in England, or in America or in Australia, they can just send an email and say they're interested in the webinar, I will put them on a list. And I will let them know when I do do webinars.

And for me, it's a little bit difficult as well, because, you know, traditional medicine and functional medicine don't always like each. So I'm not I would love to collaborate. But of course I understand as well that there's not enough research yet.

So it's always very difficult because for me, I know it has worked for me, I've done a lot of listening to podcasts and everything that are going on in the states. But before there's going to be randomised control studies are conducted, there's going to have a lot of time that is going to pass by and I don't want to let me let my patients suffer until the studies come out. You see what I mean?

Yeah, so this is the whole thing that is sometimes a little bit complicated. But I think I can help already with a lot of things. For example, with the Nurosym, a lot of other stuff that I've been doing and I can share and I want to create a community as well because people feel so alone.

And it's such a hard thing. You know, when I think it's nice if you know that the doctor has gone through this and has a searched for a lot of solutions.




That's why the story is really phenomenal because you have that medical background, the training, and the awareness and experience all wrapped into one.

And you're very good at telling your story as well. So I think that's really important and it's great. Great to hear that and great to see that you're telling people about this.

Dr Denef 

And of course if people are in Belgium because I'm going to organise days as well, like once a month, I'm going to organise a full day where people come to the clinic and when we do everything.

And I can take a full day to explain everything from A to Z. But of course, that's for people who are living more close.



Dr Denef 

The best thing is to write an email.


I'll also just add the, even though your website is in French, if anyone is using the Google Chrome browser, if they don't know it's very easy to just right click translate. And then it's all in English.

And I'm sure that's available other browsers as well. So that gives you access to a great resource as well. So yeah, thank you so much for telling your story and telling us all [your journey].

Dr Denef 

Thank you for having me, this is really great. I was really looking for a way to bring this to people and now it just came, so I'm very happy.

If I can help honestly... because I know what what kind of suffering people are going through when I read now on the books, I'm like, oh, my God, it's such it's such a nightmare.

So yeah, there is hope.



Fantastic. Thanks so much.


Dr Denef 

Thank you so much for developing this.



No problem at all. We're here to help.

In the meantime, we'll share all the links to everything that we've covered, and if anyone has any questions, they can reach out to yourself or directly to Nurosym via our form on the website.

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