Why dimming the lights helps you have a healthy baby

Dimming the lights before bedtime leads to a safer pregnancy, new research from Northwestern Medicine shows.

Mothers-to-be who spend time in low-lit rooms — along with with not-so-bright phone and computer screens — for a few hours before they go to sleep are shown to be at less risk for gestational diabetes mellitus, EurekAlert reported.

The researchers found that women who developed this type of diabetes had higher light exposure during the three hours before they had gone to sleep.

“We don’t think about the potential harm of keeping the environment bright from the moment we wake up until we go to bed,” said lead study author and Northwestern Medicine neurologist Dr. Minjee Kim.

“But it should be pretty dim for several hours before we go to bed. We probably don’t need that much light for whatever we do routinely in the evening.”


Dimming the lights three hours before bed is beneficial to the health of pregnant women, a study finds.
Dimming the lights three hours before bed is beneficial to the health of pregnant women, a study finds.
Getty Images/iStockphoto

The new information comes at a crucial time. The amount of gestational diabetes cases have risen both in the US and across the globe at “alarming” pace, Kim added.

In 2020, the rate of gestational diabetes had risen to 7.8% of all US births. It had been only about 4.5% between 2011 and 2013. It is also reported that developing gestational diabetes puts mothers at a higher risk for their next pregnancy.

“Gestational diabetes is known to increase obstetric complications, and the mother’s risk of diabetes, heart disease and dementia. The offspring also are more likely to have obesity and hypertension as they grow up,” Kim added, also saying that type 2 diabetes mellitus becomes 10 times a risk.

It is currently thought that the nighttime light exposure is causing overactivity which could impact a person’s glucose metabolism, according to Kim.


Exposure to less light before sleep is good for the health of pregnant women, new research finds.
Exposure to less light before sleep is good for the health of pregnant women, new research finds.
Getty Images/iStockphoto

“It seems there is inappropriate activation of the fight or flight response when it is time to rest,” Kim said. 

Although it remains unclear which source of bright lighting is the worst culprit of them all, Kim believes that the combination of all sorts can have overall impact. But turning off blue light features on phones and using night lights are good options, according to the neurologist.

“Turning down the lights is an easy modification you can make,” Kim, who had admittedly turned into the “light police” at their own home said. “It’s best not to use your computer or phone during this period. But if you have to use them, keep the screens as dim as possible.”