New Study Looks Into 3 Factors In Young Adults’ Mental Health

On average, the respondents had an average depression score of 19, with scores above 16 corresponding to an increased risk of clinical depression.

After reviewing external factors of depression – such as socioeconomic status, demographics, etc. – the team found that sleep, particularly sleep quality, correlated most significantly with depressive symptoms and well-being. The amount of sleep and physical activity followed. "Only one nutritional factor – the consumption of raw fruits and vegetables – predicted greater well-being, but no depressive symptoms when controlling covariates," the study says.

In the survey, the quality of sleep was measured by asking, "How refreshed do you feel when you wake up from sleep?" and amount of sleep with the question: "How many hours do you typically sleep per night in a typical week?" In this study, less than 8 hours were considered too little sleep and more than 12 hours were considered too much. In general, sleep quality is measured by the amount of time spent in two phases of sleep: REM sleep (ideally at least 20 to 25% of sleep hours) and deep sleep (ideally at least 15 to 20% of sleep hours).

Since this is a correlation study, it is difficult to prove whether poor sleep quality led to an increased risk of depression or vice versa. An increase in the depressive symptoms worsened the quality of sleep. However, the researchers write that "Evidence shows that sleep disorders are more likely to precede depression in young adults and that health behavior modification interventions lead to improvements in mental health and well-being."