Clinical trial NCT04799821: The Role of Walnut Consumption on Sleep Quality
Official title: Eat Walnuts and Sleep Better: Exploring the Potential Role of Walnuts as Sleep-promoting Food and Their Impact on Body Composition
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy Diet
Sleep
Keywords: Sleep quality
Walnuts
Body composition
Circadian rhythms
Lead sponsor: University of Barcelona
Sponsor class: OTHER
Collaborators: name: California Walnut Commission
First posted: 2021-03-16
Enrollment: 100
Sex: ALL
Minimum age (years): 20
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: OTHER

Brief summary: Walnuts have a unique nutritional profile, including the sleep-regulating hormone melatonin, tryptophan, and omega-3 fatty acids, the two latest nutrients involved in melatonin and serotonin synthesis. Although it has been claimed that walnuts may improve sleep, to the investigators' knowledge, no studies have been conducted to objectively determine the impact of walnut consumption on sleep and overall well-being. Therefore, this study aims to investigate the effect of daily walnut consumption on sleep parameters (such as quality and duration). Secondarily, it aims to investigate the impact of daily walnut consumption on body composition, eating behavior, and well-being.

Detailed description: The study to investigate the effect of daily walnut consumption on sleep quality will be conducted in an 18-week randomized crossover trial, in which participants will be initially assigned to intervention or control conditions for 8-weeks. After 2 weeks of washout, subjects will be crossed over to the alternate intervention and will continue for another 8 weeks. Note that throughout the whole study, each participant will attend 5 visits: 1 initial visit (baseline) and 2 visits in each one of the study conditions (intervention and control).

Eligibility criteria: Inclusion Criteria:

* BMI 19-26 kg/m\^2
* Habitual moderate exercise level
* No recent history of weight change exceeding 2.3kg (5lb) within the prior 3 months.

Exclusion Criteria:

* Nuts allergy
* Any acute or chronic diseases
* Smokers
* Any drugs or supplementations
* Any alimentary restrictions or specific diets
* Being a shift or night workers
* Being unable to give written informed consent.

Primary outcomes:
measure: Changes in sleep onset latency from baseline to weeks 4, 8, 14, and 18
timeFrame: Weeks 4, 8, 14 and 18
measure: Changes in sleep efficiency from baseline to weeks 4, 8, 14, and 18
timeFrame: Weeks 4, 8, 14 and 18
measure: Changes in wake after sleep onset (WASO) from baseline to weeks 4, 8, 14, and 18
timeFrame: Week 4, 8, 14, and 18
measure: Changes in sleep duration from baseline to weeks 4, 8, 14, and 18
timeFrame: Weeks 4, 8, 14, and 18
measure: Changes in urinary 6-sulphaoxymelatonin from baseline to week 4, 8, 14 and 18
timeFrame: Week 4, 8, 14 and 18
Secondary outcomes:
measure: Changes in body mass index (BMI) from baseline to weeks 4, 8, 14, and 18
timeFrame: Weeks 4, 8, 14 and 18
measure: Changes in body fat from baseline to weeks 4, 8, 14, and 18
timeFrame: Weeks 4, 8, 14 and 18
measure: Changes in weight circumference from baseline to weeks 4, 8, 14, and 18
timeFrame: Weeks 4, 8, 14 and 18
measure: Changes in eating behavior from baseline to weeks 8 and 18
timeFrame: Weeks 8 and 18
measure: Changes in well-being from baseline to weeks 8 and 18
timeFrame: Weeks 8 and 18
Other outcomes:
Locations:
city: Santa Coloma de Gramenet
country: Spain
facility: Torribera Campus, University of Barcelona
state: Barcelona
Study officials:
affiliation: University of Barcelona
name: Maria Izquierdo-Pulido, PhD
role: PRINCIPAL_INVESTIGATOR
References: