Effect of L-serin ingestion on circadian photoentrainment -a randomized, double-blind, and placebo-controlled study-

Effect of L-serin ingestion on circadian photoentrainment -a randomized, double-blind, and placebo-controlled study- - Effect of L-serin ingestion on circadian photoentrainment

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000024435

Enrollment

Registered

2016-10-17

Start date

2016-10-17

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy volunteer

Interventions

Ingestion of L-serin for two weeks Ingestion of placebo for two weeks

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Male or female univercity students or graduate students who have late sleep habits

Exclusion criteria

Exclusion criteria: 1)Subjects who take hyponotics and sedatives 2)Subjects who are shift worker or night worker 3)Subjects whose DLMO was not detected by screening test

Design outcomes

Primary

Measure	Time frame
Dim Light Melatonin Onset (DLMO)	—

Secondary

Measure	Time frame
Psychomotor Vigilance Task (PVT) Karolinska. Sleepiness Scale (KSS)	—

Countries

Japan

Contacts

Public ContactMichihiro Ohashi

Kyushu University Graduate School of Integrated Frontier Sciences

ohashi.michihiro.572@s.kyushu-u.ac.jp092-553-4523

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026