Watch Raveena Ghattaura's report for ITV News Anglia
A man who struggled to walk up the stairs because of long Covid says he is a "changed person" after taking a new treatment containing gut-friendly bacteria.
Matthew Webb from King's Lynn in Norfolk spent four weeks in hospital after getting covid before he had been vaccinated.
"I genuinely thought I might die - it was really, really awful," he said. "Being taken away from the family was rough. One minute I'm there and the next I'm being carried away.
"The ward I was in, one particular night we lost three people in one night. You wake up and three more people gone, you think am I going to be next? It was horrible."
When Mr Webb was released from hospital, it was just the beginning of a long recovery that is still under way.
"When I got home, I couldn't even get up the stairs," he said. "It was really rough, my breathing was so bad and the fatigue is the big thing.
"You have no strength. Some days there's lots of bone pain; the bones really, really hurt.
"As the treatment [goes] on you start to feel a little bit better in yourself and not as bad, but there's still the breathlessness, the exhaustion - my heart rate was 130 at rest - brain fog... [and] my taste and smell went."
Mr Webb really noticed improvements when he started taking capsules developed by scientists in Cambridge and Bedfordshire, which contain gut-friendly bacteria.
"I started taking it and within three days I felt the difference," said Mr Webb. "Three days, I was a changed person.
"Since the day I started taking it I haven't had a bad day since. Three months ago I wouldn't have been able to do half the things I've done.
"This last week I went away in my caravan for the first time, with my family.
"I'm going 18 or 20,000 steps in a day with the dog, whereas three or four months ago I'd do 3,000 steps and I'd be in bed for two days."
Professor Robert Thomas helped develop Yourgut Plus
The development of the new treatment for long covid was led by Professor Robert Thomas from Addenbrooke's Hospital in Cambridge in two studies.
Scientists have now made a further breakthrough with a second capsule containing natural ingredients such as chamomile and pomegranate.
In the first study Prof Thomas showed treating the gut to a blend of five different friendly bacteria called lactobacillus probiotics, combined with a chicory-rich ingredient known as an inulin, helped with symptoms.
In a second study, he found that a capsule containing a mix of other natural substances known as phytochemicals can significantly help further.
He said: "In our research group we designed a study looking at whether we could concentrate certain foods which would help some of the symptoms of Covid.
"The reason we used a capsule is we are able to concentrate foods in a much greater degree than you'd be able to eat.
"Also you can take them in the morning, at lunchtime and have the foods that you wouldn't normally in a British diet take at those times. So things like chamomile, pomegranate, turmeric, citrus bioflavonoids which come from berries and things.
"So the idea is you start the day boosting your diet with healthier foods.
"We then used a second capsule that had this things called phytochemicals. I call them gifts from nature which are in certain foods - herbs, spices, berries, turmeric, pomegranate.
"These work in a number of ways. They reduce excess inflammation, they help oxidative pathways, so they help the body cope with attack. They also have direct antiviral properties."
Prof Thomas’s team recruited 147 study volunteers from the Cambridge and Bedford areas with symptomatic Covid-19 from May to November 2021.
They were all given a dried lactobacillus probiotic capsule and then half were also given the phytochemical-rich concentrated food capsule, and half were given a dummy capsule called a placebo.
The results, analysed by University of Bedfordshire statisticians, revealed that symptoms improved significantly in the entire group.
On top of this, participants who took the phytochemical rich food capsule had an even better improvement compared to those who took the placebo.