Less screen time and more sleep are critical for preventing depression, a new study suggests.

An international research team found that certain lifestyle choices may have a big impact on mood. That includes having a better-quality diet, getting more physical activity and not smoking.

Australian researchers analyzed U.K. Biobank data from 85,000 people to determine impact of lifestyle on depression. They found physical activity, a healthy diet, and getting between seven and nine hours of sleep nightly was associated with less frequency of depressed mood. Screen time and tobacco smoking were significantly associated with higher frequency of depression.

"The research is the first assessment of such a broad range of lifestyle factors and its effect on depression symptoms using the large U.K. Biobank lifestyle and mood dataset," said lead co-author Jerome Sarris, a professor at Western Sydney University's NICM Health Research Institute. 

"While people usually know that physical activity is important for mood, we now have additional data showing that adequate sleep and less screen time is also critical to reduce depression," he said in a university news release.

A person's diet pattern may be partly responsible for exacerbating a depressed mood, according to the study. Surprisingly, more frequent alcohol consumption was associated with reduced frequency of depression in people with depression, according to the study. One reason may be that people with depression are self-medicating with alcohol to manage their moods.

"The results may inform public health policy by further highlighting the important relationship between people being encouraged and supported to engage in a range of health-promoting activities. In particular, maintaining optimal sleep and lessening screen time [which is often an issue in youth], while having adequate physical activity and good dietary quality, may reduce the symptoms of depression," Sarris said.

The study was published Nov. 11 in the BMC Medicine journal.