Recently, Dr. Mercola posted an article from a journal which revealed that the human body emits visible light 1,000 times less intense than what the human eye can perceive. The light is thought to be a result of free radical reactions taking place in the body. This differs from the infrared radiation which is produced from body heat. Japanese scientists explored this phenomenon with cameras capable of detecting single photons on 5 healthy male volunteers. Their findings indicated that this body light rose and fell throughout the day and that the light seemed to be linked to the body's metabolism and melanin production.
Dr. Mercola suggested that these latest research findings may be able to scientifically validate the use of energy medicine and other Eastern medical practices.
Source: http://articles.mercola.com/sites/articles/archive/2009/08/15/Your-Body-Literally-Glows-With-Light.aspx
Could your low energy be due to a vitamin deficiency? See if you recognize the signs at my home blog: http://dr-lobisco.com/blog/?p=128