The Role of Walnut Consumption on Sleep Quality

• ClinicalTrials.gov Identifier: NCT04799821
• Recruitment Status: Completed
• First Posted: March 16, 2021
• Last Update Posted: November 29, 2023
• Sponsor: University of Barcelona
• Collaborator: California Walnut Commission
• Information provided by (Responsible Party): Dra. Maria Izquierdo-Pulido, University of Barcelona

Tracking Information

• First Submitted Date: February 12, 2021
• First Posted Date: March 16, 2021
• Last Update Posted Date: November 29, 2023
• Actual Study Start Date: February 1, 2021
• Actual Primary Completion Date: July 31, 2022 (Final data collection date for primary outcome measure)

Current Primary Outcome Measures (submitted: March 17, 2021)

• Changes in sleep onset latency from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14 and 18 ]
  Measured in hours of sleep with an actigraph (ActTrust, CONDOR, Brazil)
• Changes in sleep efficiency from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14 and 18 ]
  Calculated in percentage as the ratio of total sleep time (TST) to time in bed (TIB). Sleep efficiency (percent) = (TST/TIB)*100
• Changes in wake after sleep onset (WASO) from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Week 4, 8, 14, and 18 ]
  Measured in minutes of WASO with an actigraph (ActTrust, CONDOR, Brazil)
• Changes in sleep duration from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14, and 18 ]
  Measured in hours of sleep time with an actigraph (ActTrust, CONDOR, Brazil)
• Changes in urinary 6-sulphaoxymelatonin from baseline to week 4, 8, 14 and 18 [ Time Frame: Week 4, 8, 14 and 18 ]
  Quantified using urine Melatonin-Sulfate ELISA kit

Original Primary Outcome Measures (submitted: March 11, 2021)

• Changes in sleep onset latency from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14 and 18 ]
  Measured in hours of sleep with an actigraph (ActTrust, CONDOR, Brazil)
• Changes in sleep efficiency from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14 and 18 ]
  Calculated in percentage as the ratio of total sleep time (TST) to time in bed (TIB). Sleep efficiency (%) = (TST/TIB)*100
• Changes in wake after sleep onset (WASO) from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Week 4, 8, 14, and 18 ]
  Measured in minutes of WASO with an actigraph (ActTrust, CONDOR, Brazil)
• Changes in sleep duration from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14, and 18 ]
  Measured in hours of sleep time with an actigraph (ActTrust, CONDOR, Brazil)
• Changes in urinary 6-sulphaoxymelatonin from baseline to week 4, 8, 14 and 18 [ Time Frame: Week 4, 8, 14 and 18 ]
  Quantified using urine Melatonin-Sulfate ELISA kit

Current Secondary Outcome Measures (submitted: March 11, 2021)

• Changes in body mass index (BMI) from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14 and 18 ]
  Calculated as weight (kg) divided by height (in squared meters), BMI= kg/m^2
• Changes in body fat from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14 and 18 ]
  Measured as the percentage of body fat with a body composition analyzer (Inbody 120, Korea)
• Changes in weight circumference from baseline to weeks 4, 8, 14, and 18 [ Time Frame: Weeks 4, 8, 14 and 18 ]
  Measured midway between the lower rib margin and the iliac crest with the subject standing and wearing only underwear, at the end of gentle expiration with an anthropometric tape (CESCORF, Brazil)
• Changes in eating behavior from baseline to weeks 8 and 18 [ Time Frame: Weeks 8 and 18 ]
  To evaluate changes in eating behavior, the Spanish version of the Food Cravings Questionnaire will be used (Cepeda-Benito et al, 2000). This questionnaire evaluates 10 dimensions of eating behavior:

  • Having Intentions and Plans to Consume Food
  • Anticipation of Positive Reinforcement that may Result from Eating
  • Anticipation of Relief from Negative States and Feelings as a Result of Eating
  • Lack of Control over Eating
  • Thoughts or Preoccupation with Food
  • Having Intentions and Plans to Consume Food
  • Craving as a Physiological State
  • Emotions that may be Experienced Before or During Food Cravings or Eating
  • Cues that may Trigger Food Cravings
  • Guilt from Cravings and/or for Giving in to Them

  For each subscale, scores range from 0 to 5, with higher scores indicating a stronger sensation of craving.
• Changes in well-being from baseline to weeks 8 and 18 [ Time Frame: Weeks 8 and 18 ]
  Well-being will be measured with the Spanish version of the WHO-5 Well-being Index (Lucas-Carrasco et. al. 2012). Scores range from 0 to 100, with higher scores indicating higher well-being.

• Original Secondary Outcome Measures: Same as current
• Current Other Pre-specified Outcome Measures: Not Provided
• Original Other Pre-specified Outcome Measures: Not Provided

Descriptive Information

• Brief Title: 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
• 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).
• Study Type: Interventional
• Study Phase: Not Applicable
• Study Design: Allocation: Randomized; Intervention Model: Crossover Assignment; Masking: None (Open Label); Primary Purpose: Other

Condition

• Healthy Diet
• Sleep

Intervention

• Other: Control
  Participants will be asked to refrain from walnut intake and to follow an isocaloric meal plan that complies with the recommendations of a healthy Mediterranean-style eating pattern.
• Other: Walnut intake
  Participants will be asked to consume walnuts along with an isocaloric meal plan that complies with the recommendations of a healthy Mediterranean-style eating pattern.

Study Arms

• Experimental: Intervention
  Daily walnut consumption
  Intervention: Other: Walnut intake
• Control
  No walnut consumption
  Intervention: Other: Control

• Publications *: Not Provided

Recruitment Information

• Recruitment Status: Completed
• Actual Enrollment (submitted: November 1, 2022): 100
• Original Estimated Enrollment (submitted: March 11, 2021): 110
• Actual Study Completion Date: March 31, 2023
• Actual Primary Completion Date: July 31, 2022 (Final data collection date for primary outcome measure)

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.

Sex/Gender

• Sexes Eligible for Study: All

• Ages: 20 Years to 40 Years (Adult)
• Accepts Healthy Volunteers: Yes
• Contacts: Contact information is only displayed when the study is recruiting subjects
• Listed Location Countries: Spain

Administrative Information

• NCT Number: NCT04799821
• Other Study ID Numbers: 600269
• Has Data Monitoring Committee: No

U.S. FDA-regulated Product

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No

IPD Sharing Statement

• Plan to Share IPD: No
• Plan Description: There is no plan to make IPD available.

• Current Responsible Party: Dra. Maria Izquierdo-Pulido, University of Barcelona
• Original Responsible Party: Same as current
• Current Study Sponsor: University of Barcelona
• Original Study Sponsor: Same as current
• Collaborators: California Walnut Commission

Investigators

• Principal Investigator: Maria Izquierdo-Pulido, PhD; University of Barcelona

• PRS Account: University of Barcelona
• Verification Date: November 2023