Roughly 20 percent of Americans work night shifts, forcing them to eat meals during the day and at night. A new study published in the Proceedings of the National Academy of Sciences shows that eating at these late hours increases the risk of depression and anxiety. Researchers took 12 men and seven women and created a simulated shift-work schedule, altering their normal circadian rhythms. Half of them then ate meals only during the day, while the other half ate both during the day and night. Those who ate during the night, like most night-shift workers do, had a 26 percent increase in depression levels and 16 percent higher levels of anxiety.