Effect of sleep and smart phone on serum melatonin level in first year medical students

Vinita Belsare, Mangesh Tekade, Sarika C. Munghate, Hrishikesh Belsare


Background: Poor sleep quality among students have been reported with increasing hours of usage of mobile per day. The effects of sleep on health may be mediated through the circadian hormone melatonin which has wide-reaching effects on human physiology and is an emerging biomarker for adult chronic diseases. The poor sleep quality due to academic stress and excessive use of smart phone amongst the medical students may be responsible for the disturbance in circadian rhythm and varied melatonin secretion which may have serious physical and mental health effects. The aim of study was to see the impact of sleep and smart phone usage on serum melatonin level.

Methods: Sample size was 100, 3 were absent. Questionaries’ was asked to all the study group regarding timing to go to sleep and sleep hours in night. 9 A.M Morning fasting blood samples were taken and serum melatonin was estimated by ELISA kit.

Results: Authors found only 19 students were with sleep deprivation. The average sleep hours in early sleepers was significantly more as compared to late sleepers. The study finding also suggested that there was significant usage of smart phone in late sleeper group, which may be due to high use of smart phone in the night. No association was found between bedtime and serum melatonin level. There was increase in serum melatonin in students whose usage of smart phone was high.

Conclusions: So, the students who sleeps late have less sleep duration and more usage of smart phone. Bed time, sleep duration and smart phone usage may have rhythm disturbance and phase shifting in melatonin secretion.


Melatonin levels, Sleep, Smart phone

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