How Smartphone Use Before Bed Impairs Sleep and Health

By: Isabella Pankow

Edited: Shrinidhi Sridhar

After a long day of work or studying, studies show that 86% of Americans end their days by “doom scrolling” on their phones, unaware of the impacts that this habit is having on their brains and bodies (​​Luchter, 2025). A survey done by Bank of America showed how 7 in 10 Americans sleep with or next to their phone. In addition to this phone addiction, 67% of teenagers have reported that using their phone before bed has caused them to lose sleep (Kumar 2024). Using your phone before sleep disrupts your body’s natural rhythms and sleep quality, causing both mental and physical problems as a result. 

The Circadian rhythm is the body’s internal clock that regulates our sleep cycle by responding to light and darkness. The brain’s hypothalamus contains a “master clock” called the suprachiasmatic nucleus (SCN). When the SCN receives light signals through the eyes, the SCN sends signals to make the body alert. During the evening, the SCN receives signals to lower body temperature, and activate melatonin production. Melatonin is produced by the pineal gland in the brain, and is the key hormone that causes sleep (Cleveland Clinic, 2024). 

Although the circadian rhythm is supposed to work naturally with the day’s cycle, phone usage can agitate our “body clock” by signaling our body to be artificially alert. Phones emit a type of light called “blue light” which suppresses melatonin production. This light is composed of electromagnetic radiation, an invisible form of energy that causes people to have poorer sleep quality and lower sleep durations (Newsom 2024). 

Chronic sleep deprivation due to excessive phone use may lead to health risks in the future. Being sleep deprived for long periods of time has been linked to a wide range of chronic illnesses such as diabetes, hypertension, and heart disease (Harvard, 2025). It is important to acknowledge these risks and start new habits. Research shows that putting your phone away one hour before bed has significantly improved sleep quality and health overall (Harvard, 2025). Turning your phone off is one of the easiest and most efficient ways to improve your sleep hygiene. By turning off your phone before bed, you get more hours of high quality sleep, which allows the immune system to function properly. As a result, this makes one less susceptible to illnesses, including autoimmune diseases, in the long run. 

Works cited 

Cleveland Clinic. “What Is Circadian Rhythm?” Cleveland Clinic, 15 Mar. 2024, my.clevelandclinic.org/health/articles/circadian-rhythm.

Harvard. “How Sleep Deprivation Can Harm Your Health - Harvard Health.” Harvard Health, 22July2025, www.health.harvard.edu/staying-healthy/how-sleep-deprivation-can-harm-your-health.

Kumar, Naveen. “19 Smartphone Addiction Statistics 2025 (Worldwide Data).” DemandSage, 28 Dec.2024, www.demandsage.com/smartphone-addiction-statistics/?utm_source=chatgpt.com.

Newsom, Rob, and Abhinav Singh. “How Blue Light Affects Sleep.” Sleep Foundation, 12 Jan. 2024, www.sleepfoundation.org/bedroom-environment/blue-light.

Palmer, Katie. “One Day of Sleep Deprivation Can Alter Your Immune System and Increase Inflammation- AAI News.” AAI News, 24 Feb. 2025, news.aai.org/2025/02/24/one-day-sleep-deprivation-can-alter-immune-system/.

​​Luchter, Les. “Bedtime Phone Use Affecting Americans’ Health & Work: Study.” Mediapost.com,2025, www.mediapost.com/publications/article/409500/