The biologic effects of grounding the human body during sleep as measured by cortisol levels and subjective reporting of sleep, pain, and stress.

Ghaly and Teplitz, 2004 [pilot study, n=12, male and female, from 24 to 72 years of age], aimed to test the hypothesis that grounding the human body to Earth during sleep results in quantifiable changes in cortisol. To achieve that, diurnal cortisol secretion levels and circadian cortisol profiles were measured. The authors also hypothesized that grounding the human body would result in changes in sleep, pain, and stress (anxiety, depression, irritability), which were evaluated through subjective reporting. All the subjects in the study had complaints of sleep dysfunction, pain, and stress. They were grounded to Earth during sleep for 8 weeks in their own beds using a conductive mattress pad. Saliva tests to establish cortisol levels were administered pre-intervention, also at 4-hour intervals for a 24-hour period to determine the circadian cortisol profile, and at week 6. Subjective symptoms were reported daily throughout the 8-week test period. Based on the results, the researchers concluded that grounding during sleep reduces night-time levels of cortisol and resynchronizes cortisol hormone secretion more in alignment with the natural 24-hour circadian rhythm profile.  Changes were most apparent in females. Furthermore, subjective reporting also indicated that the intervention improved sleep, reduced pain, and stress.