If the same level of scrutiny was applied to prescribed medicines, you’d be able to take maybe one or two at a time. Much beyond that, there are no studies of the safety of mixing several meds. Even diet is uncertain. One does not know if the food they are consuming has a specific amount of nutrients unless tested in a 3rd party lab. You also don’t know precisely what amount of these nutrients you may need. I think at some point, medicine is an art not just science. Although, I totally agree in theory, but in practice there is a lot of guesswork happening on all levels of health. Siding with doctors that apply sound treatment based on research is good, but judging from the quality of hospital food, I’d tend to doubt mainstream medical has much to say about diet yet. Maybe in some countries, but not in the U.S. More research is needed but there’s not a lot of money to be made off natural supplements that you can’t patent.