The Efficacy of Vitamin D Supplementation to Sustain Performance Outcomes

NCT07654777 | Recruiting

• 2 other identifiers: WRAIR #3286MO230047
• Study Type: interventional
• Target: 52
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to find out if vitamin D supplements help healthy adults maintain their cognitive and simple physical task performance and emotional state during highly stressful situations. The main question it aims to answer is: \- Does vitamin D help maintain cognitive and physical task performance and emotional state during highly stressful situations? Researchers will compare vitamin D to placebo (a look-alike tablet that contains no active ingredients) to see if vitamin D better maintain cognitive and physical task performance and emotional state during highly stressful situations. Participants will:

• Take vitamin D or placebo tablets daily for 8 weeks.
• Perform cognitive and simple physical tasks and rate their emotional state under highly stressful situations.
• Wear a stress belt that delivers mild electric shocks 1 - 5 times while participants are performing laboratory tasks.
• Wear a wristwatch-shaped activity monitor for 9 weeks.
• Visit the laboratory 5 times.

Conditions

Acute Stress Reaction

Keywords

acute stress reaction; vitamin D; electrical shocks; neuropsychological tests; randomized controlled trial

Outcome Measures

Primary Outcomes (1)

• Percentage correct for No-Go trials in the Go/No-Go task

  Measure of cognitive performance. Percentage correct for No-Go trials.

  From baseline to the end of study product supplementation at 9 weeks.

Secondary Outcomes (5)

• Mean reaction time in the Psychomotor Vigilance Task

  From baseline to the end of study product supplementation at 9 weeks.

• Scale scores of The Automated Neuropsychological Assessment Metrics (ANAM) Mood Scale

  From baseline to the end of study product supplementation at 9 weeks.

• Sway indices of Biosway

  From baseline to the end of study product supplementation at 9 weeks.

• Average Heart rate

  Heart rates are measured during the periprocedural periods of laboratory stress task at baseline and at the end of study product supplementation at 9 weeks.

• Concentration of alpha-amylase in saliva

  Saliva samples are collected during periprocedural periods of laboratory stress task at baseline and at the end of study product supplementation at 9 weeks.

Study Arms (2)

Vitamin D3

EXPERIMENTAL

Daily self-administration of two 2,000 International Unit (IU) vitamin D3 tablets for 8 weeks.

Dietary Supplement: Vitamin D3 (Cholecalciferol)

Placebo

PLACEBO COMPARATOR

Daily self-administration of two placebo tablets for 8 weeks.

Dietary Supplement: Oral Placebo Tablet

Interventions

Vitamin D3 (Cholecalciferol) DIETARY_SUPPLEMENT

4,000 IU daily oral administration for 8 weeks.

Vitamin D3

Oral Placebo Tablet DIETARY_SUPPLEMENT

Daily administration of two oral placebo tablets for 8 weeks

Placebo

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Male and non-pregnant, non-lactating females 18 to 40 (inclusive) years of age.
• Females of child-bearing potential must be using some form of birth control, if sexually active (e.g., oral contraceptive, condom, intrauterine device, etc.)
• Score of 80% or greater on a "Volunteer Comprehension Assessment" test. A maximum of two attempts is permitted.
• Blood 25 hydroxy vitamin D \[25(OH)D\] levels at the Screening visit of 30 nmol/L (12 ng/mL) (inclusive) - \< 75 nmol/L (30 ng/mL).

You may not qualify if:

• Contraindications due to vitamin D supplementation, including a history of hypercalcemia, malabsorption syndrome, hypervitaminosis D, or allergic/hypersensitivity reactions to vitamin D or a history of other adverse reactions to vitamin D supplementation.
• Not being able to tolerate electric shocks delivered through the stress belt.
• Self-reported propensity for adverse skin reactions, such as excessive irritation, burning, itching, hives, and redness, in response to physical or heat stimuli.
• A history of abuse or addiction to recreational or illicit drugs (including marijuana and alcohol) or prescribed medications (e.g., opioids) (diagnosed or suspected based on the medical history).
• Use a nicotine product (e.g., cigarette, cigar, vape) more than 3 days per week or not be able to go without using these products during any lab visits.
• Self-reported caffeine use in excess of 600 mg (e.g., approximately 10 caffeinated sodas or approximately 29 ounces of brewed coffee) per day on average or not being able to go without caffeine during the in-lab visits.
• Score of 10 or above on the Beck Depression Inventory (BDI) or a score of \> 0 on item 9 "Suicidal Thoughts or Wishes" of the BDI.
• Score of 33 or above on the Posttraumatic Stress Disorder (PTSD) Checklist, 5th Edition.
• Score 20 or above on the Patient-Reported Outcomes Measurement Information System (PROMIS) Emotional Distress-Anxiety-7-Item Short form.
• History of cardiovascular disease (to include but not limited to arrhythmias, valvular heart disease, congestive heart failure, history of sudden cardiac death or myocardial infarction).
• Asthma, any type of reactive airways disease, or any pulmonary disease requiring daily inhaler use.
• Regularly work night shifts or have a habitual sleep/wake schedule that is not conducive for the optimal performance on cognitive, physical, and/or emotional tasks during the study visits (e.g., extremely early or late habitual bedtime or rise time; to be determined on a case-by-case basis by the principal investigator or an associate investigator).
• A diagnosis of sleep apnea.
• Kidney disease or kidney abnormalities, liver disease or liver abnormalities, or any other metabolic derangements (endocrine disorders, hyperglycemia, etc.) that could alter neurophysiological function.
• History of kidney stones.

Sponsors & Collaborators

• Walter Reed Army Institute of Research (WRAIR): lead

Study Sites (1)

Sleep Research Center (SRC), Walter Reed Army Institute of Research (WRAIR)

Silver Spring, Maryland, 20910, United States

RECRUITING

MeSH Terms

Conditions

Stress Disorders, Traumatic, Acute

Interventions

Cholecalciferol

Condition Hierarchy (Ancestors)

Stress Disorders, Traumatic; Trauma and Stressor Related Disorders; Mental Disorders

Intervention Hierarchy (Ancestors)

Cholestenes; Cholestanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Sterols; Vitamin D; Secosteroids; Membrane Lipids; Lipids

Central Study Contacts

Ihori Kobayashi, Ph.D.

CONTACT

301-319-9287; ihori.kobayashi.ctr@health.mil

Lonique Moore, MSPH

CONTACT

301-319-9287; lonique.t.moore.ctr@health.mil

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: FED
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 8, 2026
• First Posted: June 17, 2026
• Study Start: June 1, 2026
• Primary Completion (Estimated): September 1, 2027
• Study Completion (Estimated): September 1, 2027
• Last Updated: June 17, 2026

Record last verified: 2026-06

Locations

US (1)