After millions of years of adaptive evolution, our bodies have become naturally suited to functioning during the day, and certain organic chemicals are released into the blood stream accordingly. Melatonin, for example, is typically released by the body at night as we are preparing to sleep. When are schedules require us to stay up through the night, however, our body tries to adjust though typically with limited success.
One study done on Canadian police officers found that only 40% adjusted from the day shift to the night beat without suffering sleep disorders. In a larger study of 3,000 officers, researchers found that 40% had difficulty adjusting to the new schedule. So sleeping at night tends to make us feel worse, but is it actually bad for our health? By increasing the likelihood of weight gain and other diet-related disorders, the answer seems to be an unequivocal yes:
A study from the University of Surrey found that “after five weeks, people who stayed awake at night and slept during the day showed impaired glucose regulation and changes in metabolism which could increase the risk of type 2 diabetes and obesity in the long-term.”
In his Big Think interview, nutrition author Jonny Bowden explains how getting adequate sleep helps maintain a healthy bodyweight: