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Dr Gareth Davies (Gruff) has BSc in Physics and PhD in Medical Physics from Imperial College, London (see full bio). Between March to July 2020, he took an unplanned sabbatical and worked pro bono as a full time coronavirus research scientist, and part-time thereafter, collaborating with a growing number of leading international scientists and doctors.

On March 10th, alarmed by the UK government’s announcement that no lockdown was needed and their claims that the UK was 28 days behind Italy, he began whistleblowing and calling for lockdown*. His model forecasts showed the UK was 14-15 days behind Italy and turned out to be precisely correct, closely matching the actual number of reported deaths. He became a signatory on the open letter signed by 500+ scientists that finally helped change government policy, albeit 10 days too late.

[* He did not support subsequent lockdowns as more became known about the virus.]

He then began to look into viral seasonality looking for clues to help fight the virus, joining forces with two medical doctors, Dr Attila Garami (Switzerland) and Dr Joanna Byers (UK). 


Between March 17th and 24th, they circulated documents [1,2,3] with compelling evidence that vitamin D deficiency was the cause of severe disease outbreaks due to compromised immune function. The documents called for hospitals to act: test, treat, measure and report, and were shared more than 20,000 times globally.

In April and May, he published 2 papers in preprint, the first as sole author, a reliable method for quantifying outbreak severity, and the second with Dr Garami and Dr Byers, formal proof that vitamin D deficiency caused severe coronavirus disease. The causal proof paper was the first study to prove of causation and attracted international attention and respect from leading researchers in the field. 

In June, the UK government finally ordered an evidence review into vitamin D and COVID19. Dr Davies’ paper was 1 of just 13 preprints acknowledged by the NICE evidence review - but was listed in an appendix of preprints excluded due not yet being peer-reviewed. Peer-review takes up to a year in normal conditions and though hundreds of studies had been published, very few had been peer-reviewed. NICE reviewed only 5 papers, 4 for the hypothesis and 1 against, ignoring the hundreds of other preprint studies on SARS-CoV-2 and vitamin D, and thousands of studies published on prior coronaviruses and vitamin D. 

NICE’s panel mis-analysed all 5 papers and concluded there was "no evidence" despite that it had looked at almost none.

Dr Davies co-led an international campaign,, backed by leading International scientists, doctors and professors to raise awareness of the solid base of scientific evidence that vitamin D deficiency is the dominant risk factor in severe coronavirus disease.

Gruff is a Codex World’s Top 50 Innovator; Machine Learning & Data Scientist, Software Engineer; Award-winning Serial Tech Entrepreneur; he has more than three decades of complex system modelling experience with a science and medical background. He worked for 2 years as a consultant at the NHS Modernisation Agency and The NHS Institute for Innovation and Improvement. 

See full bio.

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