“Natural”
medicine just means medicine derived from living things rather than
synthesized in a lab. Until the 19th century, no one knew how to
synthesize organic compounds, so “natural” medicine was the the only
kind there was. This knowledge had accumulated over millennia largely by
trial and error, so a lot of it was valid, but also a lot of it wasn’t.
Even when it was, there usually was no accurate idea of why it worked.
As
it so happened, the knowledge of how to synthesize organic compounds
developed around the same time as an understanding of how to apply
scientific method to medicine with placebo-controlled double-blind
trials (which someone has called “the most important medical invention
of all time”). And, in a capitalist context, most funding for such
systematic research has gone into synthetic treatments because these can
typically be patented, whereas natural ones can’t be.
As
a result of this coincidence, many people conflate the question of
whether a treatment is synthetic and whether it’s scientifically
validated. And some commercial interests demagogue this by appealing to
people’s suspicion of “experts” to promote things that aren’t
scientifically validated, seeking to turn this deficiency into a virtue
by labeling them “natural.”
But if
you’ll reflect on it, even mainstream doctors often give advice that
doesn’t involve anything synthetic. For a cold they’ll tell you to get
plenty of rest and fluids. They’ll tell you to increase the fiber and
reduce the sugar in your diet. Etc.
You
can’t make any sweeping generalizations; you simply have to investigate
what actual research exists on any given treatment. For this you need
to have some familiarity with scientific method and conventions.
Consider subscribing to responsible scientific publications oriented
toward the general public, such as Science News, not just reading them when you want to investigate a particular claim but regularly, to develop this familiarity.
As
a counterexample, one time a co-worker who was desperate to find a
treatment for something affecting a friend showed me an article he’d
copied about a supposed miracle cure. One “red flag” in the article was
the “citations” at the end. It was a long list of journal titles — and
that was it. They were all the titles of real medical journals, and were
obviously intended to impress a naive reader that this was serious
stuff. But if you actually had some familiarity with scientific
publications, you would recognize that this was nonsense. Each of these
journals might have several issues in any given year, with hundreds of
pages in each issue and dozens of articles whose titles would mean
nothing to a non-expert. Without even the year of publication being
given in any of these “citations” — let alone volume, issue, and page
number or article title — it was totally impracticable to verify that
they contained anything to substantiate the claims in the article. But
that wasn’t their purpose, of course — it was just to make it look “scientific.”