https://www.israelnationalnews.com/News/News.aspx/309793
Coffee offers protection against COVID-19
Really? 
Uh... no. Makes a good story, but not exactly what the article says. That is, it hints at that, but it's not really solid evidence.
Dietary Behaviors and Incident COVID-19 in the UK Biobank, by Vu et al.
https://www.mdpi.com/2072-6643/13/6/2114/htmThe UK Biobank is a project to collect data on health and behavior from a large group of people, and follow them over time. The authors were able to use that data, which includes reports from people about their diet, and look for correlations with their covid-19 test results.
They found that those who tested positive for covid-19 were a bit more likely to have reported a) drinking at least one cup of coffee per day, b) eating above the average servings of vegetables, c) not eating much processed meat, and d) having been breast-fed as an infant.
One obvious reason why this is not strong evidence is that diet was reported in 2006-2010, while covid tests were obviously at least 10 years later than that, so we can't be certain that they continued to eat the same diet in 2020.
The authors themselves admit that the data needs to be confirmed by other studies before we accept it as significant, and that even if there is a correlation, it doesn't imply that the coffee/veggie diet itself caused the somewhat lower risk of covid.
In fact, the best interpretation at this point would be what AsherO said, without any need for the /s.
To me this is obviously, coffee makes people alert and alert people pay better attention to avoiding COVID...
/s
Also, most people have heard that it's healthier to eat more vegetables and less processed meat, and those who adhere to those guidelines are also more likely to have adhered to the advice given to avoid covid.
I don't know why the news articles are quoting the coffee part, but this group of scientists has studied effects of coffee in the past, so perhaps that was emphasized somewhere and the reporters latched on to that.
