Elsevier

Fertility and Sterility

Volume 102, Issue 2, August 2014, Pages 336-338
Fertility and Sterility

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Spectral modulation of light wavelengths using optical filters: effect on melatonin secretion

https://doi.org/10.1016/j.fertnstert.2014.06.006Get rights and content
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Shiftwork has been identified as a risk factor for various medical problems, such as cancer, heart disease, metabolic disturbances, depression, and anxiety disorders, and as reviewed this month, adverse reproductive function. Shiftwork misaligns physiological rhythms with respect to each other and to external environmental rhythms such as the 24-hour light/dark cycle. Light is the strongest time cue for entraining circadian rhythms in mammals, and aberrant light exposure patterns during shiftwork is one of the key factors that induce circadian misalignment. We have recently demonstrated, in both animal and clinical models, that filtering short wavelengths (below 480 nm) from nocturnal lighting can attenuate alterations in hormone secretion (melatonin and glucocorticoids) and in central and peripheral clock gene expression induced by nighttime light exposure. We also demonstrated that the use of optical filters led to an improvement in mood and in cognitive performance under controlled laboratory conditions and during field-based shiftwork studies. Moreover, there was an increase in sleep duration and quality on nights immediately following night shifts. We believe it is likely that optical filters incorporated into glasses or as coverings for light bulbs could be used as a method to improve or prevent many of the medical problems associated with circadian misalignment and rotating shiftwork.

Key Words

Circadian rhythm
melatonin
optical filters
short wavelength light
shiftworkers
night shifts

Cited by (0)

S.R. reports grants from the Canadian Institutes of Health Research (MOP 106496); has filed 2 IPs relating to filtering short wavelengths to prevent circadian disruption; and holds stock in Melcort Inc. R.F.C. has a grant from the Canadian Institutes of Health Research (MOP 106496); is a consultant for Fertility Neutraceuticals; is medical director for Insception Cord Blood Bank; provides expert testimony for Canadian Medical Protective Association; received payment for lectures from AbbVie, Bayer, and Actavis; holds a patent for ZircLight (method for preventing shift in circadian rhythm by light at night); receives royalties from Teva and Fertilty Neutraceuticals; received payment for development of educational materials from Actavis; and holds stock in OvaScience, ZircLight, and Insception.