Two interesting researches suggest a seemingly strange thing about having a faster metabolism, a reduction in oxidative stress and better immune defenses: no specific nutrition, no fasting.

To have a faster metabolism it would be enough to sleep in a room at the “right” temperature , ie between 16 and 20 ° Celsius (or 60-67 degrees F). This temperature in the bedroom would not only promote a deeper sleep, stimulating the production of melatonin which also has antioxidant and protective virtues in our body, but would induce the body to burn more calories through a greater activation of brown fat, a particular type of fat which, as I have already pointed out in some articles, promotes thermogenesis, that is, it pushes the body to burn many more calories.

According to  Dr. Christopher Winter who heads the Charlottesville Neurology & Sleep Medicine center, sleeping in temperatures higher than 27 degrees or below 15 degrees Celsius would negatively affect metabolism, inducing greater stress. To prove him right, a 2014 study appeared in the American Diabetes Association , which correlates lower night temperatures (therefore sleeping in a cooler room) to greater thermogenesis, even during the day (i.e. a faster metabolism even during the day).
Furthermore, in a cool room, you fall asleep more deeply and the time to fall asleep is shorter , because the lower temperature favors the natural passage of the body to an already lower temperature.: Basically, our body temperature goes down at night, and this environment would favor both sleep and the production of melatonin.