The sampled hair, obtained by cutting the first inch and one half of growth closest to the scalp at the nape of the neck.  Testing is then performed using highly sophisticated detection equipment and methods to achieve the most accurate and precise result.
 
Why test for Mineral?  
Zinc is involved in the production, storage, and secretion of insulin and is necessary for growth hormones.
 
Magnesium - is required for normal muscular function, especially the heart.  A deficiency has been associated with an increase incidence of heart attacks, anxiety and nervousness.
 
Potassium - is critical for normal nutrients transport into the cell.  A deficiency can result in muscular weakness, depression and lethargy.
 
Excess sodium is associated with hypertension, but adequate amounts are required for normal health.
 
Trace elements (minerals) are "more important factors in human nutrition than vitamins.  The body can manufacture many vitamins, but it cannot produce necessary trace minerals or get rid of many possible excesses."