Recruiting

Walnut Consumption

Sponsor:

Columbia University

Code:

NCT06430086

Conditions

Poor Sleep Quality

Eligibility Criteria

Sex: All

Age: 45 - 65

Healthy Volunteers: Accepted

Interventions

Walnut consumption

HCHS consumption

Study Details

Brief summary:

Poor sleep quality is very common in modern society. Walnuts contain many nutrients that may be helpful for sleep, including melatonin and polyphenols. Some studies show that eating foods high in melatonin and polyphenols improves sleep quality, but walnuts have not been studied specifically. This study proposes to test if eating walnuts improves sleep compared to a food that lacks these sleep-promoting factors. The investigators expect that walnut consumption for 4 days will increase melatonin levels and lead to better sleep quality compared to a high-carbohydrate, high-sugar food. The study will enroll middle-aged and older adults with sleep complaints to participate in this study. Each person will eat the two different foods for 4 days each in random order. The 4-day periods will be separated by at least 2-3 weeks. Sleep quality will be measured by questionnaire and with a wrist monitor every day. The investigators will also do a sleep study using electroencephalography (EEG) on night 3 and take measures of circadian physiology (natural body rhythms) in the laboratory on day 4 (including overnight) by measuring body temperature and blood and urine melatonin. The study findings may provide new options to improve sleep health from increased walnut consumption.

Conditions

Poor Sleep Quality

Study ID

NCT06430086

Start date

Jun 28, 2024

Status verified date

Jul, 2026

Completion date

Dec 31, 2026

Anticipated

Primary completion date

Dec 31, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 45 - 65

Healthy Volunteers: Accepted

Inclusion Criteria:

  • Equal numbers of men and women (12 male and 12 post-menopausal female)
  • Equal number of individuals with normal weight (18.5-24.9 kg/m2) and overweight (25-29.9 kg/m2)
  • Participants will self-report poor sleep quality, reflected by a global score >5 on Pittsburgh Sleep Quality Index

Exclusion Criteria:

  • Diagnosed sleep disorder
  • Participants with conditions that could affect sleep will be excluded:

  • smoking, excessive caffeine intake (>300 mg/day)
  • shift work
  • chronic pain
  • diagnosis of a chronic disease (e.g., uncontrolled hypertension, pre-diabetes, type 2 diabetes, chronic kidney disease, chronic obstructive pulmonary disease),
  • autoimmune diseases
  • cardiovascular event or cancer in the past 24 months
  • psychiatric/neurologic disease or disorder, or sleep disorder (diagnosed or high risk for sleep apnea, chronic insomnia, restless leg syndrome, narcolepsy)
  • use of medications that influence CYP1A2 enzymes
  • Allergy/intolerance to nuts, tree nuts, or unwilling to eat study foods

Study Design

Enrollment

24 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Walnut - washout - HCHS

Participants will consume 3 servings/day of walnuts (3 oz/d) over 4 days and have a washout for 2-3 weeks then crossover to consume 3 equicaloric servings of a HCHS food over 4 days.

Over each 4-day period, participants will sleep and eat at home for the first 3 days and will be admitted to the Inpatient Clinical Research Resource of the Irving Institute for Clinical and Translational Research of CUIMC on day 4 for in-depth profiling circadian physiology. Participants will be discharged on the morning of day 5.

experimental: HCHS - washout - Walnut

Participants will consume 3 equicaloric servings of a HCHS food over 4 days and have a washout for 2-3 weeks then crossover to consume 3 servings/day of walnuts (3 oz/d) for 4 days.

Over each 4-day period, participants will sleep and eat at home for the first 3 days and will be admitted to the Inpatient Clinical Research Resource of the Irving Institute for Clinical and Translational Research of CUIMC on day 4 for in-depth profiling circadian physiology. Participants will be discharged on the morning of day 5.

Interventions

Walnut consumption

Participants will add one serving (1 oz) of walnuts at their self-defined breakfast, lunch, and dinner for 4 days. The study will provide study foods at 3 main meals each day to evaluate a temporal effect of the food on melatonin concentrations throughout the day.

HCHS consumption

Participants will add one HCHS food (one PopTarts® pastry) to each of their 3 main meals of the day for 4 days. The study will provide study foods at 3 main meals each day to evaluate a temporal effect of the food on melatonin concentrations throughout the day.

An energy-matched high-carbohydrate, high-sugar (HCHS) alternative, representative of a common US snack food, on sleep quality in adults with habitually poor sleep quality.

Primary outcome measure

  • Serum melatonin [ Time Frame: Baseline (9AM; Hour 0), Hour 1, Hour 2, Hour 3, Hour 4, Hour 5, Hour 6, Hour 7, Hour 8, Hour 9, Hour 10, Hour 11, Hour 12, Hour 13, Hour 14, Hour 15 (Midnight) ]
  • Sleep quality index [ Time Frame: Night 1, Night 2, Night 3, Night 4 ]
  • Slow wave sleep index [ Time Frame: Night 3 ]

Central Contacts and Locations

Central contacts

Joseariel Romero

347-963-8845jr4119@cumc.columbia.edu

Locations

Columbia University Irving Medical Center

Recruiting

New York, New York, United States, 10032

Contacts

Joseariel Romero

347-963-8845jr4119@cumc.columbia.edu

Principal Investigator:

Marie-Pierre St-Onge, PhD

More Information

Sponsor

Columbia University

Last update posted

Jul 31, 2026

Last verified

Jul, 2026

Keywords

  • Randomized crossover study
  • Controlled feeding
  • Dietary intervention
  • Inpatient visit
  • Outpatient monitoring

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Columbia University on 2026-07-31.