Have you ever worried about whether your cell phone could cause cancer? If so, you were most likely worried about whether holding the phone close to your head could give you a brain tumor.

However, you may have also read about a 2018 study published in Environmental Health Perspectives. This study looked at whether nighttime exposure to blue light could be linked to an increased risk of cancers related to sex hormones, such as prostate cancer. The scientists who conducted the study found that men who were exposed to more blue light at night had twice the risk of prostate cancer.

One source of blue light for many of us is our phones. The Pew Research Center reports that 97% of people between the ages of 18 and 49 own a smartphone, and only 89% of people between the ages of 50 and 64 do. In addition, a survey by Sleepopolis found that 2 in 3 people spend the majority of their evening staring at screens.

Given the ubiquity of cell phone use, the question arises whether men who use their phones frequently should be concerned about prostate cancer because of radiation or blue light exposure. To get answers, Health Digest interviewed Justin Houman MD, FACS, assistant professor in the department of urology at Cedars-Sinai Medical Center.

“The biggest concern about cell phones is that radiofrequency radiation may increase the risk of certain types of cancer, particularly brain tumors,” Houman explained, adding that to date there have been no large-scale studies or research confirming a link between cell phone radiation and cancer.

Houman added that the evidence for a link between cell phones and prostate cancer is even weaker. “Current scientific consensus is that the RF levels emitted by cell phones are too low to cause significant biological damage that would lead to cancer, including prostate cancer.”

Houman did not comment specifically on research related to blue light and prostate cancer, but noted that blue light can have harmful health effects. “The blue light emitted by screens can interfere with melatonin production and potentially disrupt sleep patterns if the devices are used late at night,” he said.

So what should men do to protect themselves? “Although the evidence of significant health risks from cell phones is not yet clear, it makes sense to take some simple precautions,” Houman said. To reduce radiation exposure, he advises using hands-free devices, limiting phone use, texting instead of calling, and not sleeping with the phone nearby or under the pillow.

When it comes to blue light, you’ll want to keep an eye on your screen time, especially close to bedtime. Plus, according to Sleep Doctor, it’s not just our phones that we need to watch out for. Fluorescent lights, LED bulbs, TVs, computer screens, tablets, e-readers, and video game consoles can all mess up our circadian rhythm.

To reduce the harmful effects of blue light on sleep, Sleep Doctor recommends turning off your electronic devices two to three hours before bedtime. Also, dim or turn off your lights and use lamps that emit red or orange light instead of blue light. When using your phone or other devices, make sure you use “night mode” if your device has it. There are also apps that can help you reduce your blue light exposure. Finally, if there are lights you can’t turn off, try blocking them out with an eye mask after you lie down to sleep.