40000 people 6-year study reminds: the stronger the artificial light in sleep, the more likely to get fat

I've heard that staying up late makes people fat, and pressure makes people fatBut have you ever thought that you might get fat even if you sleep well? Does this seem unscientific? A large study from the National Institutes of Health (NIH) for the first time found that artificial light in the night sleep environment was related to weight gain, and the latest results were published in JAMA internal medicine< br / > source: JAMA internal medicine < br / > previous studies have shown that people who work at night tend to gain weightFor the general population, although the exposure intensity of artificial light at night is far lower, there are not a few people who are used to sleeping with lights on and watching TVDoes that have a long-term impact? That's exactly what this study is going to answer< br / > the researchers included data for 43222 womenThese women, aged 35-74, had no history of cancer or cardiovascular disease, were not shift workers at the start of the study, had no habit of sleeping during the day, and were not pregnantThrough a questionnaire survey, the researchers collected the sleeping light environment of these women, such as whether it is completely dark, or with a small night light, or with a light outside the window, or with a light in the room, or with a television and other artificial light sources< br / > at the study baseline, the researchers measured their weight, height, waist circumference, hip circumference and body mass index (BMI)The data showed that women who had any artificial light in the sleep environment were generally fatter and all indicators were higher< br / > before and after an average follow-up of 5.7 years, the researchers also collected self-reported body weight data of the subjects to analyze the relationship between sleep environment and the weight change of these women in five yearsStatistics showed that the stronger the artificial light in the sleep environment, the more obvious the tendency of the subjects to gain weight< br / > compared with the dark environment, there was no significant change in the body weight of the people who used the small night light, while the light outside the room was related to the small increase in body weightMore women who slept with lights on or TV on had significant weight changes, with a 17% higher risk of gaining more than 5 kg during the follow-up periodAccording to BMI changes, the risk of becoming overweight (BMI ≥ 25) increased by 22%, and the risk of becoming obese (BMI ≥ 30) increased by 33%Compared with those who were already obese at baseline, the trend of weight gain was more obvious in women with normal or overweight baseline< br / > of course, as an observational study, other confounding factors may also affect weight changes However, after adjusting for age, family members, race, socio-economic status, calorie intake, physical activity and sleep duration, the overall trend remained consistent The findings are also consistent with current recommendations: sleep should be as dark as possible < br / > the co authors of the study, Dr Yong moon park and Dr Chandra Jackson of the National Institute of Environmental Health Sciences in the United States, pointed out that "human beings are born to be more adaptable to the natural environment with clear day and night." However, for modern life, street lights, shop signs and other artificial light sources at night are very common < br / > exposure to artificial light at night can inhibit the secretion of sleep hormone melatonin, affect the 24-hour circadian rhythm of the human body, and may also disrupt stress hormones and other metabolic processes, thus increasing health risks such as obesity In addition, light may also affect the quality of sleep, disrupt appetite hormones and lead to eating more, or affect the amount of physical activity due to lack of sleep < br / > in addition, although the study did not specifically assess the impact of light on smartphones, computer screens or tablets, previous studies have also shown that the blue light emitted by these devices is related to poor sleep, daytime sleepiness, etc The authors suggest that night blue light exposure may also be associated with obesity, but further confirmation is needed "Although unhealthy, high calorie diet and sedentary behavior are the most common factors of obesity, this study highlights the important impact of artificial light, and it is expected that the incidence rate of obesity will be reduced by adjusting the sleeping environment," said first author Yong-Moon Park < br / > reference materials < br / > [1] Yong moon mark Park, et al., 2019 Association of exposure to artistic light at night while sleeping with risk of obsity in women JAMA internal medicine, 10.1001/jamantinnmed.2019.0571 < br / > [2] sleeping with artistic light at night associated with weight gain in women Retrieved Jun 11, 2019, From < br / > [3] keeping your TV on at night may lead to weight gain Retrieved Jun 11, 2019, from < br / > [4] expert reaction to study on artistic light at night and visibility risk?! This habit is very important, 40000 people have studied for six years!