Sleep disturbance

Disturbance to sleep is one of the symptoms often reported as part of hypersensitivity.  The World Health Organization Environmental Health Criteria in 2008 found just two laboratory studies of magnetic fields and sleep disturbance.

Their conclusion from chapter 1, the summary chapter, is:

"Studies investigating whether magnetic fields affect sleep quality have reported inconsistent results. It is possible that these inconsistencies may be attributable in part to differences in the design of the studies."

The full discussion comes in chapter 5:

"5.2.5 Sleep

Sleep is a complex biological process controlled by the central nervous system and is necessary for general health and well-being. The possibility that EMFs may exert a detrimental effect on sleep has been examined in two studies. Using the EEG to assess sleep parameters, Åkerstedt et al. (1999) reported that continuous exposure of healthy volunteers to 50 Hz at 1 µT at night caused disturbances in sleep. In this study, total sleep time, sleep efficiency, slow-wave sleep (stage III and IV), and slow-wave activity were significantly reduced by exposure, as was subjective depth of sleep. Graham & Cook (1999) reported that intermittent, but not continuous, exposure to 60 Hz, 28 µT magnetic fields at night resulted in less total sleep time, reduced sleep efficiency, increased time in stage II sleep, decreased time in rapid eye movement (REM) sleep and increased latency to first REM period. Consistent with a pattern of poor and broken sleep, volunteers exposed to the intermittent field also reported sleeping less well and feeling less rested in the morning.

A comparison between these two studies is made difficult because of the differences in the exposure levels used, 1 µT (Åkerstedt et al., 1999) vs. 28 µT (Graham & Cook, 1999) and also of other differences in the design. As to the results, in the Åkerstedt study, results were apparently obtained by low-level continuous exposure, whereas the Graham study failed to elicit such results by continuous exposure, but did produce similar results with intermittent exposures. Further studies with similar designs are needed before any conclusions can be drawn."