Many biologically active chemicals have been identified in nature.
Aspirin (or at least salicylic acid compounds) is in wintergreen and willow bark. Opioids are derived from poppy sap, and eating too many poppyseeds will make you test positive for opium metabolites. Digoxin for heart failure and atrial fibrillation comes from foxgloves.
Coffee, specifically, has tons of data pointing to it improving cardiovascular health including this massive meta-analysis covering 1,279,804 people [1]. This meta-analysis shows a reduction in inflammation from consuming coffee [2].
I'm not denying any of that. What I'm saying is that when you randomly give a person a weak cocktail of random alkaloids and then ask them if they feel better, you're going to get a very unscientific mix of placebo and outright false information.
When you repeat such an experiment on large sample sizes with no control over the other myriad of environmental influences on the subjects, even after attempting to control for confounding factors you're still going to end up with extremely noisy data made effectively useless by just as many contradicting studies which find no effect. You see it all over the place - eggs and cholesterol, coffee harm/benefit, wine harm/benefit. These studies are all intimately highly flawed because they are empirical soft sciences with very little control over the large number of chaotic interactions among and within their subjects.
So when people say things like "drink coffee and eat lettuce to control inflammation during COVID infection" without a disclaimer, they're being [unknowingly] irresponsible, to say the least. Especially considering the dose of active compound in something like lettuce is likely to be totally insignificant.
If you are taking care of someone who could die, the most legally defensible choice is to follow medically recommended procedures. But if the medical establishment is giving you an emoji shrug and you could die because of it, that's when it might make sense to take advice from internet strangers.
Aspirin (or at least salicylic acid compounds) is in wintergreen and willow bark. Opioids are derived from poppy sap, and eating too many poppyseeds will make you test positive for opium metabolites. Digoxin for heart failure and atrial fibrillation comes from foxgloves.
Coffee, specifically, has tons of data pointing to it improving cardiovascular health including this massive meta-analysis covering 1,279,804 people [1]. This meta-analysis shows a reduction in inflammation from consuming coffee [2].
[1] https://www.ahajournals.org/doi/full/10.1161/CIRCULATIONAHA....
[2] https://www.ncbi.nlm.nih.gov/pubmed/28967799