The more artificial light you get during sleep, the more likely you are to gain weight
"Humans are naturally more attuned to the natural environment of clear day and night."
I've heard that staying up late and stress can make you fat. Does that sound not scientific? But a study from the United States has found for the first time that artificial light in a nighttime sleep environment is associated with weight gain.
Studies have shown that people who work night shifts tend to get fat. For the general population, exposure to artificial light at night is much lower, but there are plenty of people who sleep with the lights on and watching TV. That's the question this study aims to answer.
In all, the researchers included data from 43,222 women. The women were 35 to 74 years old, had no history of cancer or cardiovascular disease, were not shift workers at the start of the study, had no daytime sleep habits and were not pregnant. Using a questionnaire, the researchers collected information about the women's sleep lighting environment, such as whether it was completely dark, with night lights on, or if there were artificial lights outside the window. At the baseline, the researchers measured their weight, height, waist circumference, hip circumference and body mass index (BMI), and the data showed that women with any artificial light in their sleep environment were generally fatter and had higher levels of all indicators.
The researchers also collected self-reported weight data before and after an average of 5.7 years of follow-up to analyze the relationship between sleep environment and the women's weight changes over a five-year period.Statistically, the more artificial light in the sleep environment, the fatter the subjects tended to be.
Compared with dark environments, there was no significant change in weight in people who used small night lights, and light outside the room was associated with a small increase in weight. More women who slept with the lights on or the TV on showed significant weight changes.
Of course, as an observational study, other things may also affect weight change. However, the overall trend remained consistent after adjusting for age, family members, race, socioeconomic status, calorie intake, physical activity and sleep duration. The findings are also consistent with current recommendations that sleep should be kept as dark as possible.
Exposure to artificial light at night suppresses the sleep hormone melatonin, affects the body's 24-hour circadian rhythm, and may also disrupt stress hormones and other metabolic processes, increasing health risks such as obesity.In addition, light may affect sleep quality, disrupt appetite hormones to eat more, or interfere with physical activity due to lack of sleep.
While unhealthy, high-calorie diets and sedentary behavior are the most common factors of obesity, the study highlights the important role of artificial light in potentially reducing the incidence of obesity by modifying the sleep environment.
I've heard that staying up late and stress can make you fat. Does that sound not scientific? But a study from the United States has found for the first time that artificial light in a nighttime sleep environment is associated with weight gain.
Studies have shown that people who work night shifts tend to get fat. For the general population, exposure to artificial light at night is much lower, but there are plenty of people who sleep with the lights on and watching TV. That's the question this study aims to answer.
In all, the researchers included data from 43,222 women. The women were 35 to 74 years old, had no history of cancer or cardiovascular disease, were not shift workers at the start of the study, had no daytime sleep habits and were not pregnant. Using a questionnaire, the researchers collected information about the women's sleep lighting environment, such as whether it was completely dark, with night lights on, or if there were artificial lights outside the window. At the baseline, the researchers measured their weight, height, waist circumference, hip circumference and body mass index (BMI), and the data showed that women with any artificial light in their sleep environment were generally fatter and had higher levels of all indicators.
The researchers also collected self-reported weight data before and after an average of 5.7 years of follow-up to analyze the relationship between sleep environment and the women's weight changes over a five-year period.Statistically, the more artificial light in the sleep environment, the fatter the subjects tended to be.
Compared with dark environments, there was no significant change in weight in people who used small night lights, and light outside the room was associated with a small increase in weight. More women who slept with the lights on or the TV on showed significant weight changes.
Of course, as an observational study, other things may also affect weight change. However, the overall trend remained consistent after adjusting for age, family members, race, socioeconomic status, calorie intake, physical activity and sleep duration. The findings are also consistent with current recommendations that sleep should be kept as dark as possible.
Exposure to artificial light at night suppresses the sleep hormone melatonin, affects the body's 24-hour circadian rhythm, and may also disrupt stress hormones and other metabolic processes, increasing health risks such as obesity.In addition, light may affect sleep quality, disrupt appetite hormones to eat more, or interfere with physical activity due to lack of sleep.
While unhealthy, high-calorie diets and sedentary behavior are the most common factors of obesity, the study highlights the important role of artificial light in potentially reducing the incidence of obesity by modifying the sleep environment.
