By refining or synthesizing various compounds, toxicity is created. In other words, because they are presented to the body stripped of other substances that act as balancing agents, these artificial compounds are not well received by the body.
In most cases, each of a drug's therapeutic effects comes with a negative side effect. Granted, the newly created drug may be more potent, administered with great precision and easier to ingest, but the human body has a tendency to recognized it as a foreign and unnatural substance. As a result, a chain of a desirable physiological reactions occurs. Frequently, the body reacts to synthetic and powerful compounds much as it would to a poison.
The bottom line is that nature usually knows best. It is important, though, to remember that unlike the potent, quick and sometimes dangerous effects of synthetic drugs or analogs, herbs works slowly. Rather than masking symptoms, herbs intrinsically heal - and their side effects are longer lasting.
While plants have provided medicine with some of it's best drugs, artificial synthesis of chemical compounds found in specific plants has unfortunately suffered the search for new and better plant sources. Synthesized compounds can be patented, but often, the enormous amount of money needed to bring that compound into therapeutic dispersion is difficult to recoup.
European and Asian countries have continued to study and value the use of herbal preparations and are far ahead of the United States in regard to herbal medicines and their practical applications. Phytomedicinals are largely sold in these countries where laws requiring their safety and efficacy are more reasonable than in an American communities.
Source: 365 Days to Health & Wellness by: Espie Chinel Aparis