Researchers at the University of California, Irvine studied the long-term effects of stress in a study that considered how negative reactions to stressful situations can correspond to later incidences of depression and anxiety. The study was based on data pulled from national surveys like the Midlife Development in the United States Series and the National Study of Daily Experiences. It was published in the journal Psychological Science

The study took a longitudinal view of people’s reactions to stressful situations. They compiled data on around 700 participants between the ages of 25 and 74. Their stress profiles included information about daily stressors and reactions to stress for eight consecutive days. The participants recorded what things caused them stress and their emotional states afterwards.

A key piece of the information was that participants also noted if they were experiencing negative feelings from the previous day’s stress. Even if no stressful events were recorded for a particular day, the participants still noted whether any negativity had carried over from the previous. They used words such as like hopelessness, worthlessness, nervousness, restlessness to describe their emotional states.

The group of people that reported the most negative feelings from stress was also the group that had the highest incidence of depression and anxiety ten years later. This finding was not a surprise to the researchers. Additionally, people who felt the most stressed from the previous day—whose emotions “bled over”—were the most likely to experience depression and anxiety later on.

These findings indicate that it is important for people to not hold on to stressful feelings from day to day, but that they should find ways to de-stress or otherwise discharge their negative emotions so that these emotions do not compound and lead to emotional issues later on. Managing stress is an important part of emotional regulation.