RecruitingBehavioural interventionEffect of Sleep Extension on Ceramides in People with Overweight and ObesityThe overall goal is to determine how a sleep extension intervention (increasing time in bed) in individuals who maintain less than 6.5 hours sleep per night affects their plasma ceramides and insulin sensitivity. Participants will undergo a randomized controlled trial, with sleep extension (intervention) and healthy lifestyle (control) groups. The sleep extension is designed to increase participant's time in bed by 2 hours per night. Alternatively, the control group will receive basic health information (e.g., physical activity, goal setting, and nutrition when eating out).