Overweight is connected to a sedentary lifestyle, bad diet choices, short sleeps and, from today, we know also that it may depend from artificial light in the room or from the outside. This is the result of a very recent study published in the journal JAMA Internal Medicine by a team of American scientists (Yong-Moon Mark Park et al, JAMA, June 2019).
The researchers tried to understand the role played by a light in a dark room and if a luminous source could cause a weight gain. To answer to this question they analyzed the habits of 43722 women aged between 35 and 72. What has emerged is that the women that used to sleep with a light or television on showed a 17% more probability to gain 5 kg of body weight in the following 5 years in comparison to the women that, on the contrary, slept in the darkness. The registered effect was more modest, but still present, in case of artificial light from the outside such as lamps or neon. The effect of these lights is, according to the authors of the study, to modify the body hormones thus affecting the biological processes and increasing the risk of showing overweight or obesity.
According to the study, a little choice such as turning off light and television may have a great impact and benefits on the health by playing a role in keeping at bay the body weight.