Effects of Single-Dose Nicotinamide Riboside (NR) on Sleep

Sleep quality is a major component of overall health, yet many adults experience mild but persistent sleep difficulties. Nicotinamide riboside (NR) is a naturally occurring precursor of NAD+, a key coenzyme involved in cellular energy metabolism and circadian regulation. Preclinical studies suggest that NR may influence neural pathways related to sleep-wake control, but its short-term effects on human sleep have not been well established.

This study is designed to explore the acute impact of NR on sleep in healthy adults with mild subjective sleep complaints. It uses a randomized, double-blind, placebo-controlled design to minimize bias. All participants will spend two consecutive nights in a controlled sleep laboratory. The first night serves as a baseline assessment of natural sleep. On the second night, individuals will receive a single 600 mg dose of NR or a matched placebo one hour before bedtime.

Polysomnography (PSG) will be used to evaluate objective sleep parameters, with the prespecified primary outcome being the change in N3 (slow-wave) sleep duration from the baseline night to the intervention night. Secondary PSG outcomes include changes in total sleep time, sleep efficiency, sleep onset latency, wake after sleep onset, arousal frequency, N1, N2 and REM sleep durations, and REM sleep onset latency. Subjective sleep quality is assessed using the Leeds Sleep Evaluation Questionnaire (LSEQ) on the morning after the intervention night. Safety will be monitored throughout the study period and through a follow-up contact after discharge. This exploratory early-phase study aims to generate human data on the feasibility, safety, and acute effects of NR on both subjective and objective sleep-related measures.

Inclusion criteria

• Healthy males or females aged 18 to 60 years inclusive;
• Screening using the Pittsburgh Sleep Quality Index (PSQI) scale with a total score between 5 and 10, indicating mild subjective sleep disturbance;
• Voluntarily participate in this study and sign a written informed consent form;
• Able to understand the study procedures and willing to comply with all laboratory regulations.

Exclusion criteria

• History of any serious neurological, cardiovascular, respiratory, hepatic, renal, hematological, or psychiatric disorders;
• Medically diagnosed sleep disorders (e.g., insomnia, sleep apnea syndrome, restless legs syndrome);
• Regular use within the past month of any medication or supplement that may affect sleep (e.g., sedatives, antidepressants, antihistamines, melatonin);
• Known allergy to nicotinamide riboside (NR) or any component of the study product;
• History of chronic smoking, heavy alcohol consumption (exceeding weekly recommended intake), or substance abuse;
• Participation in any other interventional clinical studies within one month prior to study initiation, or exposure to circadian rhythm-disrupting factors such as trans-time zone travel or frequent night shifts;
• Pregnant women, breastfeeding women, or men of reproductive age with plans to conceive within the next month who are not using effective contraception.