Grant: Master's Award: Canada Graduate Scholarships

In today's 24/7 world, teens are busy with school and friends. They stay up late and text-message their friends while they fall asleep. Teens chaotic sleep schedules lead to phase delay, meaning their internal clock is not synced with their bed and wake-times. Changes in sleep patterns are linked to depression. And, poorer sleep leads to more severe depression symptoms. Sleep changes and depression are also linked to light exposure and Vitamin D. Vitamin D is a hormone made in the body when it is exposed to sunlight. Scientists have started to find that Vitamin D itself is linked to sleep cycles and depression symptoms. While many studies have shown that sleep phase delay is related to depression in adolescents, scientists are still learning more about how they are related. The goal of this study is to see how light exposure and Vitamin D impact the link between sleep and depression in teens. Adolescents taking part in the Healthy Heart Project at Concordia University will have their sleep measured by wearing sensors when they sleep. They will also provide saliva samples to measure melatonin to check how synced their internal clocks are. Participants will answer questions about their mood and depression symptoms. And, they will have a blood test to look at Vitamin D levels. The results will help scientists better understand how sleep and depression are linked, which can lead to improved teen mental health.