New Research Specifies How Young Adults Can Best Protect Mental Health

While COVID-19 hasn't been easy on anyone, young people, in particular, are struggling with mental health1 during the pandemic. Research from Mental Health America found that 9.7% of youth in the U.S. showed symptoms of severe depression in 2020, compared to 9.2% in 2019.

For this new research, published in the journal Frontiers in Psychology2 in December, psychology researchers at the University of Otago in New Zealand studied what they referred to as the "big three" health behaviors: sleep, physical activity, and diet. Previous research has confirmed that these three buckets affect mental health. This team wanted to take this a step further to see which one had the most significant impact on depressive symptoms, at least in young adults.

The Otago team surveyed 1,111 young adults ages 18 to 25 who lived in either New Zealand or the U.S. The cohort was a mix of college-attending and non-college-attending men and women, nearly 70% of whom were free of diagnosed health conditions. At the time of study, 20% were on antidepressants.

On average, those surveyed had an average depression score of 19, with scores over 16 corresponding to an increased risk of clinical depression.

After controlling for outside contributors to depression—such as socioeconomic status, demographics, etc.—the team found that sleep, specifically sleep quality, most significantly correlated to depressive symptoms and well-being. It was followed by sleep quantity and physical activity. "Only one dietary factor—raw fruit and vegetable consumption—predicted greater well-being but not depressive symptoms when controlling for covariates," the study reads.

The survey measured sleep quality with the question, "When you wake up from sleeping, how refreshed do you feel?" and sleep quantity with the question, "In a typical week, how many hours do you usually sleep per night?" In this study, anything less than eight hours was considered too little sleep, and more than 12 hours was too much. Generally, sleep quality is measured by the amount of time spent in two sleep phases: REM sleep (ideally at least 20 to 25% of sleeping hours) and deep sleep (ideally at least 15 to 20% of sleeping hours).

To have more consistently restful sleep, experts recommend cutting distractions in your bedroom, reducing screen time at night, starting and sticking to a wind-down routine, maintaining a steady sleep schedule (even on weekends!), and avoiding alcohol and heavy meals before bed. You might also find success with a sleep supplement.* Melatonin is a popular pick for cueing the body that it's time to go to sleep, making it good for those who often travel to new time zones or keep wonky sleep schedules. Magnesium is often the better choice for all-around sleep quality since it's more effective at leading to longer, deeper sleep4.*