Maintaining a healthy lifestyle is an important contributor to physical and mental health. Getting adequate high-quality sleep, engaging in physical activity, and eating well have advantages to mental health such as the reduced risk of depression and anxiety, as well as increased psychological well-being.
Healthy lifestyles may be especially important for the mental health and well being of young adults as emerging adulthood is a time of developmental and ecological changes that are marked with increased responsibility, new roles, and changing life circumstances, that often coincides with the transition to work or university and changing routines as well as living situations that can disrupt health behaviors.
Studies suggest that emerging adults appear to be more vulnerable to poorer mental health, this may indicate a role for unhealthy lifestyles contributing to poorer emotional functioning. Research has shown the mental and well-being benefits of sleep, physical activity, and diet as individual predictors, this study investigated how self-reported sleep, physical activity, and dietary factors together predicted differences in mental health and well being in young adults and whether there were any higher-order interactions among these behaviors in the prediction patterns.
In this study, more than 1100 young adults from America and New Zealand were surveyed about their sleep, physical activity, diet, and mental health. According to lead author Shay-Ruby Wickham who completed this study as part of her Master of Science, sleep quality rather than sleep quantity was found to be the strongest predictor of mental health and well-being.
“This is surprising because sleep recommendations predominantly focus on quantity rather than quality. While we did see that both too little sleep — less than eight hours — and too much sleep — more than 12 hours — were associated with higher depressive symptoms and lower well-being, sleep quality significantly outranked sleep quantity in predicting mental health and well-being.”
“This suggests that sleep quality should be promoted alongside sleep quantity as tools for improving mental health and well-being within young adults,” Ms. Wickham says.
In addition to quality sleep, in this order, exercising and consuming more raw fruits and vegetables were found to be the three modifiable behaviors that correlated with better mental health and well-being in the young adults.
For those that slept 9.7 hour hours per night depressive symptoms were the lowest, and feelings of well-being were the highest for those who slept 8 hours per night. Those who consumed 4.8 servings of raw fruit/veggies per day had the highest well-being, while those who ate less than 2 servings and those who ate more than 8 servings reported lower feelings of well-being.
“Sleep, physical activity, and a healthy diet can be thought of as three pillars of health, which could contribute to promoting optimal well-being among young adults, a population where the prevalence of mental disorders is high and well-being is suboptimal,” Ms. Wickham says.
While stressing that their findings were correlations only, senior author Associate Professor Tamlin Conner of the Department of Psychology says, “We showed that they are all important for predicting which young adults are flourishing versus suffering.“
According to Conner, most prior research examines these health behaviors in isolation of each other. “We didn’t manipulate sleep, activity, or diet to test their changes on mental health and well-being. Other research has done that and has found positive benefits. Our research suggests that a ‘whole health’ intervention prioritising sleep, exercise, and fruit and vegetable intake together, could be the next logical step in this research,” she says.
Abstract:
Method: In a cross-sectional survey design, 1,111 young adults (28.4% men) ages 18–25 from New Zealand and the United States answered an online survey measuring typical sleep quantity and quality; physical activity; and consumption of raw and processed fruit and vegetables, fast food, sweets, and soda, along with extensive covariates (including demographics, socioeconomic status, body mass index, alcohol use, smoking, and health conditions) and the outcome measures of depressive symptoms [measured by the Center for Epidemiological Depression Scale (CES-D)] and well-being (measured by the Flourishing Scale).
Results: Controlling for covariates, sleep quality was the strongest predictor of depressive symptoms and well-being, 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. There were some higher-order interactions among health behaviors in predicting the outcomes, but these did not survive cross-validation.
Conclusion: Sleep quality is an important predictor of mental health and well-being in young adults, whereas physical activity and diet are secondary but still significant factors. Although strictly correlational, these patterns suggest that future interventions could prioritize sleep quality to maximize mental health and well-being in young adults.
