Many people sleep with their cellphone close by, assuming it’s harmless. In reality, this habit can disrupt recovery. As the article notes, “the blue light emitted by phone screens suppresses melatonin, the hormone that regulates your sleep–wake cycle,” making it harder for the brain to wind down. Even short exposure can delay deep sleep and leave you tired the next day.

Keeping a phone nearby also affects the nervous system. Notifications, vibrations, or simply expecting messages can keep the body alert. This constant low-level stimulation “prevents the body from fully relaxing and can fragment sleep without you even realizing it,” slowly increasing stress and irritability.

Over time, poor sleep can affect mental health. Disrupted rest has been linked to “difficulty concentrating” and a “higher risk of anxiety and mood disturbances.” You may spend enough hours in bed but still wake up feeling unfocused or emotionally drained.

Physical health can suffer as well. The article explains that poor sleep is tied to “weakened immune function, weight gain, and higher levels of inflammation.” Sleeping in awkward positions to accommodate a phone can also cause neck pain, headaches, stiff shoulders, or numb hands.

The biggest issue may be how this habit changes your relationship with rest. When your phone is “the last thing you see at night and the first thing you reach for in the morning,” your brain never fully disconnects. Creating distance—like charging your phone outside the bedroom or using an alarm clock—can help restore deeper, more refreshing sleep.