The goal of this clinical trial is to test in Japanese adults who feel sleepy when they wake up. The question it aims to answer are:

•Does taking plasmalogens reduce sleepiness upon waking?

Participants will be given the following tasks:

• Take 4 capsules daily containing plasmalogens for 12 weeks.
• Answer the questionnaire on sleepiness1 when they wake up.
• Answer the questionnaire on daytime sleepiness2. Researchers will compare plasmalogens and placebo groups to see if plasmalogens reduce sleepiness upon waking.

Inclusion Criteria:

1. Japanese
2. Men or women
3. Adults
4. Healthy individuals
5. Individuals whose Zc score of "sleepiness on rising" is relatively low at screening

Exclusion Criteria:

1. Individuals who are undergoing medical treatment or have a medical history of malignant tumor, heart failure, or myocardial infarction
2. Individuals who have a pacemaker or an implantable cardioverter defibrillator (ICD)
3. Individuals who are currently undergoing treatment of any of the following chronic diseases: cardiac arrhythmia, liver disorder, chronic kidney disease, cerebrovascular disorder, rheumatic disease, diabetes mellitus, dyslipidemia, hypertension, or any other chronic diseases
4. Individuals who are undergoing medical treatment or have a medical history of any of the following diseases: mental disorders (e.g., depression), sleep apnea syndrome, hypersomnia, narcolepsy, insomnia, or valvular heart disease
5. Individuals who have habits of consuming foods or using devices to improve sleep
6. Individuals who have irregular sleeping habits due to lifestyle such as night shifts
7. Individuals who fall under the following sleeping conditions: sleeping in the same room with two or more people, living with preschool-aged children, living with individuals who require nursing care, or having their sleep potentially disturbed by the influence of others
8. Individuals who have nocturia two times or more
9. Individuals who usually drink to excess (average of more than about 20 g/day as absolute alcohol intake) {500 mL: a medium bottle of beer or about 1.5 cans of canned chu-hi, 180 mL: 1 go of sake or about 1.5 glasses of wine, 90 mL: half-go with shochu, 60 mL: a glass of whiskey brandy (double)}
10. Individuals who are taking "Foods for Specified Health Uses" or "Foods with Functional Claims"
11. Individuals who are taking medications (including herbal medicines) or supplements
12. Individuals who are allergic to medicines or foods related to the test product, or have a gelatin allergy or sea squirt-induced asthma
13. Individuals who are pregnant, lactating, or planning to become pregnant during this study
14. Individuals who have been enrolled in other clinical studies within the last 28 days before the agreement to participate in this study or plan to participate in another study during this study
15. Individuals who are judged as ineligible to participate in this study by the physician

Data sharing will be discussed among the research affiliates after the study is completed.