"but they are scientists and take many drugs and supplements"
Of course they take many drugs - drugs came from so-called science and scientists believe in science the way Christians believe in Jesus, even though the science of today often becomes discredited tomorrow.
Natural health advocates believe in nature. And nature is the same tomorrow as is today and was yesterday.
I just read today, from a doctor, that during the last 27 years fully half of the drugs approved by the FDA have been recalled due to causing deaths. Each year over 100,000 people die from properly prescribed and used drugs. Supplements can only be blamed for a handfull.
I vote with nature - if nature did not provide it, I really don't want it in my body.