According to the National Center for Complementary and Integrative Health (NCCIH), this category of complementary therapies involves the use of various types of energy fields. In general, the goal of energy therapies is to bring energy into the patient or balance the energy within a patient.
There are many kinds of energy therapies, some which use treatments such as light, sound, and magnets. These treatments are relatively easy to measure. Other kinds of energy therapies, such as Healing Touch, Reiki, Qigong, and therapeutic touch, are "intended to affect energy fields that purportedly surround and penetrate the human body." These therapies cannot be as easily measured or researched.
Even though the results of these therapies have not been measured quantitatively in a reliable way, some new instruments, such as the superconducting quantum interference device (SQUID) are showing promise for research with energy therapies.
Moreover, and importantly, many of the techniques used in energy therapies come from practices in shamanistic and Asian traditions with thousands of years of use. For example, more than 2,000 years ago, Asian healers believed that the flow and balance of life energies were important in maintaining health, and that illnesses were due to energy imbalances. They developed therapies and practices, such as acupuncture, yoga, and Qigong to correct these imbalances. Modern energy therapies such as Healing Touch are based on the same principles.