Volume No. 10 Issue No.: 4 Page No.: 693-699 April-June 2016

 

EFFECT OF LIGHT AT NIGHT ON MELATONIN RHYTHM IN HUMAN VOLUNTEERS

 

Shedpure M.*, Karanjgaonkar P. and Ratre M.

Chronophysiology laboratory, Department of Zoology, Government D. B. Girls’ P. G. (Auto.)College, Raipur, Chhattisgarh (INDIA)

 

Received on : January 15, 2016

 

ABSTRACT

 

Melatonin has been found to be associated with the disturbances of human circadian rhythm in connection with jetlag and shift work. The control of melatonin production is primarily modulated by the photoperiod. In fact, different types of sleep problems prevalent among the shift workers and those who fly across time zones are attributed to the disturbances in the circadian physiology. Further, it has been unequivocally accepted that sleep is vital for mental and physical health of an individual. Night time light exposure between dusk and bedtime strongly suppresses the production of melatonin. It can seriously impact body's internal clock, even leading to metabolic changes and weight gain. Disrupting natural rhythm can also make more susceptible to disease like cancer, especially breast cancer, obesity, diabetes, depression and mood disorders, reproductive problems, cardiovascular disease etc. It has become a common practice for young adults to go to bed late and get up late during the morning. The purposes and mechanisms of sleep are only moderately clear and are the subject of intense research. Recently, American Medical Association [AMA] also released a report highlighting the urgent need for more studies in this area. Therefore, it has been thought worthwhile to study the circadian rhythm of salivary melatonin and actual light exposure of subjects during their normal daily activities. Results revealed that 27% of the studied individuals have reported deep sleep whose mid sleep was located around 02:29 h coincided with melatonin peak. However, 73% individuals reported disturbed sleep and their mid sleep was located around 04:24 h. Further, obesity has become a major health problem because it shows increasing prevalence and is related to multiple medical consequences. Results of Analysis of Variance (ANOVA) revealed a statistically significant effect of age on BMI. In general, it has been noticed that BMI increased with age and decreased with late bed time.

 

Keywords : Sleep-wake cycle, Melatonin rhythm, BMI, Obesity, Health problem

 

 

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