Scientists at Brigham Women's Hospital in Boston have shown that eating at night is harmful to mental health, increasing the level of anxiety and depression. This is reported in an article published in the journal Proceedings of the National Academy of Sciences (PNAS).
To conduct the experiment, the scientists included 12 men and 7 women in a randomized controlled trial. The participants underwent a protocol of forced desynchronization in dim light for four 28-hour "days", so that by the fourth day their behavioral cycles were inverted by 12 hours.
Participants were randomly assigned to one of two groups by meal time: a control group that ate according to a 28-hour cycle. As a result, they ate both at night and during the day, which is typical for night workers, and a group that ate on a 24-hour cycle, which led to eating only during the day.
Experts found that in a group whose participants ate during the day and at night, the mood level resembling depression increased by 26 percent, and the mood level resembling anxiety increased by 16 percent. According to the authors, the choice of meal time is a new strategy for improving mood in people experiencing circadian rhythm disorders.
The risk group includes those who work the night shift. Shift workers often experience a mismatch between their central circadian clock in the brain and everyday behaviors such as sleep/wake cycles and fasting/eating. They also have a 25-40 percent higher risk of depression and anxiety.