According to a new study, light during sleep in older individuals is associated with higher rates of hypertension, diabetes and obesity. Smartphones, lights or TV left on at night have also been found to significantly increase risk.
Study results demonstrated that 552 older women and men between the ages 63-84 who were exposed to any light while sleeping experienced significantly greater risks of diabetes, obesity, and hypertension compared to those not exposed at all during the night.
An illuminated wrist-worn device was used to measure exposure to light for seven consecutive days and was monitored.
This was a real-world study rather than an experimental one and found any exposure to light during the night to be associated with an increased risk of diabetes, hypertension, and obesity among older individuals.
No matter where the source of light comes from – from television and smartphone screens left on over night, to light pollution in large cities – artificial illumination exists around us all day long. Older individuals already face higher risks for cardiovascular disease and diabetes; therefore researchers aimed to see whether night-time exposure was linked with any differential disease frequencies.
Researchers discovered that only 51% of individuals participating in their study experienced 5-hour periods of complete darkness per day; most others still received some light exposure during these 5-hour dark periods that typically occurred during nighttime rest.
Researchers do not have enough information to know with absolute certainty if hypertension, diabetes, and obesity are the reasons that people sleep with lights on or if the presence of light increases risk for these conditions to form. People living with these conditions could use reason such as bathroom use at night or having foot numbness due to diabetes that requires them to keep a night light on to reduce falls risk.
Researchers offered tips to reduce light while sleeping:
Avoid leaving lights on; if necessary, switch on only dim lighting nearer to the floor and preferably orange/red/amber hued lights which stimulate less of our brain than blue or white ones that should remain distant from sleeping individuals.
Eye masks or blackout shades may help control outdoor light levels if it cannot be controlled, by shifting your bed so as to block its path from shining directly on your face.
