This interventional, double-blind, randomized, placebo-controlled pilot study aims to evaluate the effect of a dietary supplementation of a fish hydrolysate Peptidyss on sleep quality and anxiety.

A total of 44 healthy participants (n=22 female, n=22 male) aged 35-60 years inclusive are included into the study, in a cross-over design. The participants will take both products, the fish hydrolysate Peptidyss and the placebo during a period of 4 weeks per product. The total duration of the study per participant is 127 days. The study visits are defined as Screening Visit and Study Inclusion (V0), Pre-Intervention-1-Visit (V1), Post-Intervention-1-Visit (V2), Follow-up-Intervention-1-Visit / Pre-Intervention-2-Visit (V3), Post-Intervention-2-Visit (V4) and Follow-up-Intervention-2-Visit (V5). The 4 weeks between V2 and V3 will serve as a washout phase between Intervention-1 and Intervention-2. No further follow-up visit is planned.

The primary objective is to evaluate the efficacy of Peptidyss® on sleep quality.

The secondary objectives are to evaluate the efficacy of Peptidyss® on sleep quality, anxiety, perceived stress and quality of life.

Inclusion Criteria:

• Voluntary, written, informed consent to participate in the study
• Male or female aged between 35-60 years (inclusive)
• Body mass index (BMI) between ≥18.0 - ≤35.0 kg/m2
• PSQI score ≥6 (low perceived sleep quality)
• Medical questionnaire at baseline indicates they are healthy in the opinion of the Investigator
• Ability of the participant to comprehend the full nature and purpose of the study including possible risks and side effects in the opinion of the Investigator
• Agreement to comply with the protocol and study restrictions
• Available for all study visits
• Agreement to refrain from heavy drinking, late-night alcohol and late-night caffeine during the study
• Females of child-bearing potential required to provide a negative urine pregnancy test
• Easy access to internet, using email on a daily basis.

Exclusion Criteria:

• Any known history of a disorder affecting sleep quality, such as narcolepsy, obstructive sleep apnea (OSA), restless leg syndrome (RLS), periodic limb movement syndrome (PLMS) or any condition which contraindicates, in the Investigator's judgement, entry to the study
• Self-reported diagnosis of one or more DSM-V axis 1 disorder(s), including but not limited to current depression, anxiety disorder, bipolar spectrum disorder or schizophrenia
• Have a significant acute or chronic coexisting illness or any condition which contraindicates entry to the study in the opinion of the Investigator
• Previous (last 4 weeks prior to screening) or current intake of psychoactive medication (anxiolytics, sedatives, hypnotics, anti-psychotics, anti-depressants, anti-convulsants, centrally acting corticosteroids, opioid pain relievers)
• History of use (within 1 month of the first visit) or current intake (from day of screening onwards) of medication or dietary supplements/oriental herbs that could influence sleep patterns or that the Investigator believes would interfere with the objectives of the study, pose a safety risk or confound the interpretation of the study results (e.g. melatonin, omega-3 dietary supplements, non-steroidal anti-inflammatory drugs (NSAIDS), over-the-counter (OTC) sleep medication (not categorized as sedatives, hypnotics or anti-depressants), anti-coagulants, proton pump inhibitors, anti-histamines, pseudoephedrine, cortisone, beta-blockers)
• Self-declared illicit drug users (including cannabis and cocaine) for 3 months prior to screening and during the intervention period
• Heavy smoking (>10 cigarettes/day)
• High caffeine intake (> 10 cups /day) (or equivalent caffeine intake from other caffeinated drinks e.g., tea, energy drinks),
• Work schedule that causes irregular sleep pattern (e.g. night shift)
• History of travel to a different time zone within 1 month of the first visit or/and during the study participation
• Pregnant or lactating female, or pregnancy planned during intervention period
• Not fluent in German
• Contraindication or allergy (e.g. fish allergy) to any substance in the investigational product
• Participation in another study with any investigational product within 30 days of screening and during the intervention period
• Investigator believes that the participant may be uncooperative and/or noncompliant and should therefore not participate in the study.