The traditional characteristics of natures (cold, cool, hot and warm) appky to herbs and others as well.  Knowing your body's constitution and the nature of foods are necessary to help you eat right.  The proper combination balances the food nature and enhances the remedies benefits.  When the body is in balance, it is in good health andis more resilient to illnesses.

Today, most of the valuable herbs are preserved and bleached to suit the market need.  Sulfur dioxide is used to preserve red dates, chrysanthemum and codonopsis; white fungus and black fungus are treated with hydrogen peroxide (bleaching agent) to preserve the appearance.  It is not advisable to consume these herbs due to adverse effect from the chemical residue.  In addition, the chemical residue may interfer with the microorganism activity and cause failure in fermentation.