Dr.Steve's BOTTOM LINE: Have you ever wondered why some prescription meds come in a dark bottle or need refrigeration? They won't "spoil" like food might, but often sunlight or warm temperatures will cause them to become inactive and stop working. It stands to reason that many Traditional Chinese Herbs (and others) have the same limitation, being sensitive to heat and light.

This research paper summarizes what herbs are sensitive to what and how you should best preserve them. However, if you don't have time to pull the paper from your local library or online resource, here is the bottom line. First off, make sure you pay attention to labels as to expiration dates, if they are present. Also, the major sensitivity is to extremes of bright light and higher heat. If you live in a very sunny and very hot locale, you might want to refrigerate most of your herbs, which keeps out both the heat and the high intensity light. However, if you are in more moderate climes then simply keeping them in a reasonably cool , dark and decently humidified area would be fine......like a pantry area or closet. For details, check out this report which reviews hundreds of papers originally written in Chinese over the years.

Stability of active ingredients of traditional Chinese medicine (TCM).

Nat Prod Commun. 2009 Dec;4(12):1761-76

Authors: Meng W, Xiaoliang R, Xiumei G, Vincieri FF, Bilia AR

Studies on stability of active ingredients are fundamental and critical for the rational development of Traditional Chinese Medicine (TCM) in view of its modernization and worldwide use. The stability of both active and marker constituents of plants used in TCM is reviewed for the first time. More than 100 papers, mostly written in Chinese, have been reviewed. Studies concerning plant constituents were analyzed according to their chemical classification of active ingredients. In addition, several crude drugs of animal origin are also reported. Stability of active ingredients is summarized during extraction and/or storage of the herbal drug preparations, and under stress conditions (pH, temperature, solvents, light, and humidity) and in the presence of preservatives, antioxidants, and metals.

PMID: 20120121 [PubMed - in process]