Grape seed extract's effect on cholesterol in night shift workers

Effect of a Grape Seed Proanthocyanidin Extract (GSPE) on LDL Cholesterol Levels in Rotating Night Shift Workers With Moderate Hypercholesterolemia. Randomized, Crossover, Controlled and Triple Blind Study.(CIRCAFENOL)

NA · Fundació Eurecat · NCT06422741

This study is testing if taking grape seed extract every day can help lower bad cholesterol levels in people who work night shifts.

Quick facts

PhaseNA
Study typeInterventional
Enrollment22 (estimated)
Ages18 Years and up
SexAll
SponsorFundació Eurecat (other)
Locations2 sites (Reus, Tarragona and 1 other locations)
Trial IDNCT06422741 on ClinicalTrials.gov

What this trial studies

This study evaluates the impact of daily intake of grape seed proanthocyanidin extract (GSPE) on LDL cholesterol levels in individuals who work rotating night shifts. It aims to address the health risks associated with disrupted circadian rhythms, particularly focusing on cardiovascular health and metabolic syndrome. Participants will undergo a randomized, crossover, placebo-controlled design, with multiple visits to assess various health parameters, including blood pressure, lipid metabolism, and sleep quality. The study will involve 22 volunteers aged 18 and older who meet specific inclusion criteria related to their work schedule and cholesterol levels.

Who should consider this trial

Good fit: Ideal candidates are men and women aged 18 years or older who have been working rotating night shifts for at least one year and have LDL cholesterol levels between 116 and 190 mg/dL.

Not a fit: Patients with a BMI over 30 kg/m2 or those currently taking lipid-lowering medications will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved cholesterol management and cardiovascular health for night shift workers.

How similar studies have performed: While there is evidence linking night shift work to health issues, the specific approach of using GSPE in this context is novel and has not been extensively tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Men and women aged 18 years or older.
* Follow a rotating night shift work schedule\* for at least one year before the start of the study.

  \* shift workers with at least 5 night shifts per month alternating with day and/or afternoon shifts, with a seniority equal to or greater than one year.
* Have no intention of changing the work shift during the course of the study.
* Circulating LDL-C levels between 116 -190 mg/dL\*, without pharmacological treatment with antihypertensives and/or lipid-lowering agents.

  \*Values of 116 to 190 mg/dl indicate moderate alteration in the lipid profile and a greater risk of suffering from cardiovascular diseases, according to the European Society of Cardiology, and the European Society of Atherosclerosis.
* Have signed the informed consent before starting the study.
* Know how to read, write and speak in Catalan or Spanish

Exclusion Criteria:

* BMI values \> 30 kg/m2
* Take supplements, multivitamin supplements (Vit.D, Vit. E and Vit.C), mineral supplements (Zinc, Selenium), essential fatty acids (omega-3), polyphenols, natural plant extracts, or phytotherapeutic products that interfere with the treatment under study.
* Consumption of alcoholic beverages:

  * Men: consume 4 or more Standard Beverage Units daily or 28 Standard Beverage Units weekly.
  * Women: Consume 2 or more Standard Beverage Units daily or 17 Standard Beverage Units weekly.
* Be an active smoker.
* Having lost more than 3 kg of weight in the last 3 months.
* Present food intolerances and/or allergies related to the study products, such as hypersensitivity to cellulose or proanthocyanidins.
* Present any chronic or autoimmune disease in clinical manifestation that may affect the results of the study such as diabetes (type I or II), cardiovascular disease, chronic kidney disease, hyper or hypothyroidism, chronic gastrointestinal diseases or cancer.
* Present familial hypercholesterolemia.
* Present hypertension (Systolic ≥140 mmHg; Diastolic ≥90 mmHg)
* Present any previous cardiovascular disease defined as myocardial infarction, angina pectoris, stroke or peripheral arterial disease.
* Individuals with treatment in the last 3 months before the start of the study with lipid-lowering, antidiabetic and/or antihypertensive drugs, or other drugs that may interfere with the results of the study.
* Taking supplements with polyphenol components or those aimed at lipid or blood pressure control in the last 3 months before the start of the study or during participation in the study.
* Follow a diet to lose weight, or very restrictive types of eating, such as intermittent fasting, ketogenic diet, etc.
* Being pregnant or intending to become pregnant.
* Being breastfeeding.
* Be participating or have participated in a clinical trial with medications or nutritional intervention study in the last 30 days before inclusion in the study.
* Suffering from eating disorders or psychiatric disorders.
* Being unable to follow study guidelines.

Where this trial is running

Reus, Tarragona and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Cardiovascular Diseases, Circadian Rhythm Sleep Disorder, Shift Work Type, Cholesterol Level, High, Proanthocyanidins, Circadian Rhythm, Metabolic Syndrome, Melatonin, Polyphenols

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.