Sleep Restriction and Parental History of Hypertension

Inclusion Criteria * Healthy adults aged 18-35 years * Absence of any significant medical or psychiatric disease (as per the investigators' judgment) * Nonsmoker * Nonpregnant * History of normal sleep duration (reported average sleep duration between 7-9 hours/night and no habitual napping) * Hypertension status information available for both biological parents * Ability to understand study procedures and to comply with them for the entire length of the study * Ability to understand English and provide informed consent Exclusion Criteria * Age \<18 or \>35 years * Body mass index \<18.5 or ≥30 kg/m2 * Pregnant or lactating * Unable to determine history of HTN in participant's biological parents or subject being adopted * Use of tobacco, vaping, marijuana products or other drugs * Excessive caffeine consumption (\>400 mg/day) * Excessive alcohol consumption (\>7 drinks/week for women, \>14 drinks/week for men) * Office SBP/DBP ≥130/80 mmHg * Daytime ambulatory SBP/DBP ≥130/80 mmHg * Fasting glucose ≥126 mg/dl * Glomerular filtration rate \<60 mL/min/BSA * History of significant medical or psychiatric disorders (as per the investigators' judgment) * Regular use of prescription medications other than contraceptives * Use of melatonin supplements or any other over-the-counter sleep aid * Moderate-to-severe sleep disordered breathing (apnea/hypopnea index, AHI ≥15) or mild sleep disordered breathing (AHI 5-15) with daytime sleepiness (Epworth Sleepiness Scale \>10) * Moderate-to-severe insomnia (Insomnia Severity Index \>14) * Restless leg syndrome (as per the Cambridge-Hopkins questionnaire) * Excessive daytime sleepiness (Epworth Sleepiness Scale \>15) * Extreme chronotype (Morningness-Eveningness Questionnaire \>69 or \<31) * Night shift work * Ongoing participation in other research studies (as per the investigators' judgment) * Any other medical, geographic, or social factor making study participation impractical * Not English-speaking and/or inability to provide informed consent * Exclusionary for blood draws: hemoglobin \<11.6 g/dL in women / \<13.2 g/dL in men; participants with measured hemoglobin levels below these thresholds will be allowed to continue participate in study tests and procedures not involving blood draws.