Using a smartphone in bed before sleep disrupts melatonin production and delays the onset of restorative sleep, according to a study cited in a Gujarati-language health report.
Blue light from screens interferes with the body’s natural sleep cycle
The report explains that exposure to blue light emitted by mobile phones suppresses melatonin, the hormone responsible for signaling sleepiness to the brain. This delay can push back sleep onset by an average of 30 to 60 minutes, reducing total sleep duration even if wake-up time remains fixed. Over time, this pattern contributes to chronic sleep deprivation, which is linked to impaired cognitive function, weakened immunity, and increased risk of metabolic disorders.
Poor sleep quality affects cardiovascular and mental health
The article notes that disrupted sleep from nighttime screen leverage is associated with higher blood pressure, elevated heart rate variability, and increased inflammation — all risk factors for cardiovascular disease. It also cites correlations between pre-sleep smartphone use and heightened anxiety, rumination, and difficulty disengaging from mental stimulation, which further undermines sleep quality. These effects are particularly pronounced in adolescents and young adults, whose circadian rhythms are more sensitive to light exposure.
For more on this story, see Blue Light & Skin: Does Screen Time Cause Wrinkles & Pigmentation?.
Experts recommend screen-free wind-down routines before bed
To mitigate these effects, health professionals advise avoiding screens for at least 60 minutes before bedtime, using night mode or blue light filters if device use is unavoidable, and replacing scrolling with calming activities such as reading a physical book or practicing light stretching. The report emphasizes that consistent sleep hygiene — including fixed bedtimes and a dark, cool bedroom environment — remains the most effective way to support long-term health.
This follows our earlier report, World Sleep Day: 10 Tips for Better Sleep from Korean Experts.
How long before bed should I stop using my phone?
At least 60 minutes before bedtime is recommended to allow melatonin levels to rise naturally.
Can using night mode on my phone fully prevent sleep disruption?
Night mode reduces blue light exposure but does not eliminate it; mental engagement from content still interferes with sleep onset, so limiting use is still advised.