We’ve become a 24-hour culture. It used to be that the only place to find a restaurant or hardware store open at 3 a.m. was New York City. Today, even the smallest communities have a 24-hour convenience store or burger joint. Our mobile phones buzz and blink with new emails and texts at all hours. Televisions and computer screens light up our rooms most of the night.
While all these tools and conveniences make things easier for people who have to work through the night, including police officers, doctors, and nurses, research suggests that women who work at night have a higher risk of breast cancer compared to women who work during the day.
But what is it about working at night that seems to increase the risk of breast cancer? There may be several reasons. Women who work at night tend to weigh more, exercise less, and consume more junk food. They also tend to be exposed to much more light each 24-hour day than women who work during the day.
Concern about potentially higher breast cancer risk from too much light and not enough darkness was further illuminated (pun intended) by a fascinating study from Israel. It showed that women who live in areas with extra external light at night (through street lights, clocks, bathroom nightlights, and other sources) have a higher risk of breast cancer.
Too much light exposure at night may increase breast cancer risk by lowering levels of melatonin, a hormone that helps regulate the body’s sleep cycle and normal cell function. Melatonin production peaks at night and is lower during the day when your eyes register light exposure. Women who work at night or who have a lot of outside light at night tend to have low melatonin levels. Research suggests that normal night melatonin levels can encourage normal cell growth and limit the development of cancer cell activity.
Even though the connection between light and breast cancer risk isn’t completely understood yet, we all know how much better we feel and function when we’ve had a good night’s sleep. In my house, sleep is KING. We all try to help each other get as much quality sleep as possible.
So what’s the best way to block out light at night, short of sleeping in a cave? Below are the changes I’ve made. All the changes have made a big difference and all have become indispensable to my day and night rituals.
Consider thick curtains and an eye mask. It’s not clear how much light exposure at night decreases melatonin production. And while closing your eyes does a fairly good job of blocking light, installing thick curtains, blackout shades, and/or wearing an eye mask can help make sure you’re sleeping in darkness.
Don’t turn on the lights if you get up at night. Use low-wattage or red bulbs in nightlights around the house and in bathroom(s).
Cover up your clock. If you have an illuminated clock next to your bed, dim it to the lowest level, cover it with a heavy cloth, or put a book in front of it so the light doesn’t disturb your sleep.
Keep your phone or computer in a room that isn’t your bedroom. Keep all electronics that light up out of the bedroom. If they must be there, turn them off so they don’t give off any light.
Try to expose yourself to morning sunlight. Some researchers think that exposure to only dim light during the day also decreases how much melatonin your body produces. For example, if you leave for work before the sun comes up and work until the sun goes down in an area with no windows, you get almost no exposure to natural light. Most researchers agree that people exposed to bright sunlight in the morning begin producing melatonin sooner in the evening. Depending on what time you get up and the temperature, try drinking your coffee or tea outside when the sun is bright. Besides healthy light, you’ll also be exposing yourself to a shot of beauty to start your day (particularly at sunrise). If it’s too cold to stand outside, try to stand in front of a window that faces east.
Check with your doctor if you’re considering supplements. Some people say taking melatonin supplements helps them sleep better. But no research has studied melatonin supplements and breast cancer risk. Before you take any supplements, talk to your doctor about the risks and benefits of the product.
Do you sleep better in a pitch-dark room? Have you tried any of these methods to reduce light in your bedroom and noticed a difference?
Visit the Breast Cancer Risk Factors: Light Exposure at Night page for more information.