Cardiovascular Risk and Circadian Misalignment in Short Sleepers - Role of Extended Eating Period

Short sleep duration is associated with increased cardiovascular and metabolic risk with consequent increased cardiovascular mortality. Increasing sleep duration mitigates the metabolic impairment, but alternate strategies to reduce cardiometabolic risk in habitual short sleepers are lacking. This is especially important when increasing sleep duration is unsuccessful. Unfortunately, the underlying mechanisms through which shortened sleep contributes to metabolic detriments are not completely understood. This hinders the development of alternate strategies for cardiovascular prevention in short sleepers. However, a widespread factor potentially underlying metabolic dysfunction in short sleepers seems to be circadian misalignment (decreased and delayed melatonin secretion) partly resulting from mistimed eating. Importantly, eating behavior may be targeted to improve metabolism in short sleepers. Specifically, limiting the daily eating period as shown by the many recent interventions of time restricted eating (TRE) may potentiate circadian alignment (melatonin rhythms) and improve metabolism in habitual short sleepers. The goal of the study is to examine the metabolic and circadian effects of eating duration in habitual short sleepers. The investigators propose a two-group, parallel arm study during which participants will be randomized to either continue with habitual \>14h/day (extended) or restricted 8h/day (TRE) eating duration. The overarching hypothesis is that extended eating duration contributes to high blood pressure (BP), insulin resistance (IR), and a decreased and delayed melatonin secretion in habitual short sleepers. Therefore, TRE will reduce BP, IR along with an increased and earlier onset of melatonin secretion.