Turmeric

Not quite the panacea the natural advocates would hope.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3535097/

https://www.sciencebasedmedicine.org/turmeric-tasty-in-curry-questionable-as-medicine/

It's bioavailability is very poor also: "In humans receiving a dose of 2 g of curcumin alone, serum levels of curcumin were either undetectable or very low." So in most medical trials some aid to absorption or decrease in metabolic destruction is also used: Neither curcumin nor turmeric taken orally is well absorbed unless taken with black pepper or piperine, a constituent of black pepper responsible for its pungency.

---Steve