In today’s world smartphones are everywhere, placing work-related emails, texts, and calls within arm’s reach 24/7. But new research cautions that using smartphones late at night to do bedside business may not be the smartest move prompting bad sleep, while sapping focus and energy the following day.

Concern arises from the results of two new studies. The first looked at nighttime smartphone habits among more than 80 upper-level managers. All were asked to reveal how much they used their phones to conduct work after 9 PM how much and how well they slept at night how tired they were the next morning and how focused they felt throughout the workday.

The second survey questioned more than 160 employees from a wide range of fields, including chemists, paralegals, and retail workers. In addition to tallying nighttime smartphone use, this group was also asked much they watched TV at night, and how often they used their computer or tablet to do work.

Survey responses suggested that work-related smartphone use at night undermined sleep both mentally and physically interfered with the ability to relax and detach and sent the sleep hormone melatonin out of whack. The result: a worse day at the office. Another interesting finding Smartphones had a larger negative effect than watching TV or using a laptop or tablet.

I’m Dr. Cindy Haines of HealthDay TV with the latest breakthroughs from the world of medicine.

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