A study from North Carolina State University has found that unhealthy eating at night can make people less helpful and more withdrawn at work the next day.

Researchers asked 97 full-time US employees to answer three sets of questions over 10 working days.

Before work, study participants answered questions about their physical and emotional well-being that morning. At the end of each workday, they responded to questions about what they did during the day. And before bed, they answered questions about their eating and drinking behavior after work.

The researchers defined unhealthy eating as instances when the study participants felt they'd had too much to eat or drink, eaten too much junk food, or had too many late-night snacks.

The researchers found that when participants said they had eaten badly or had too much to drink, they were more likely to report physical problems such as headaches and stomachaches the next day. They were also more likely to experience emotional tension, such as feeling guilty about their diet choices.

These physical and emotional feelings then impacted participants' behavior at work. They became less willing to help their colleagues if they felt they didn't have to. They were also more withdrawn, choosing to avoid work-related situations if they thought they could, despite being at their place of work.

Seonghee Cho, one of the study authors, explained that we already know a lot about how behaviors like sleep and exercise can affect our work. She says her study shows that what we eat and drink can have an almost immediate effect on work performance too.

However, she said that because the questions also asked about drinking, it wasn't clear if some behavior was just due to the effects of alcohol.

She said she also wants to study how people's behavior is affected by what they eat during the day, and whether unhealthy eating could actually help people handle stress.