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Posted May 26, 2015

Skin Measurement Device Used to Select Nutritional Supplements Not Approved for This Use, FDA Warns

On May 8, 2015, the FDA issued a warning letter to ZYTO Technologies, Inc., following a facility inspection which found the company promoted its "galvanic skin response measurement device" (the ZYTO Hand Cradle) for uses for which it is not intended -- such as identifying diseases and selecting nutritional supplements. 

This type of device is designed to measure changes in the electrical properties of the skin, which can fluctuate when a person sweats, or experiences stress. It is sometimes sold to natural health practitioners such as chiropractors, acupuncturists and nutritionists. However, it cannot be legally marketed in the U.S. for diagnostic or treatment purposes. (See the article on for more about the regulation of these devices). 

Statements on the company's website and in product brochures described the device this way: "ZYTO's technology measures your body's responses to a specific library of nutritional products, asking your body which it prefers; this is called biocommunication." A booklet for practitioners stated: "General nutritional assistance biosurveys will help to identify your patient's biological preference for the products you sell. Other biosurveys may provide you with information specific to disease, toxins or organs and body functions.

To read the FDA's warning, use the link below.