Metabolic Effects of Linoleic Acid-Rich Oil Compared to a Blend Oil in Adults With Insulin Resistance

NCT07287514 | Recruiting

• 2 other identifiers: 23033001811240454
• Study Type: interventional
• Target: 120
• Locations: 1 country
• Sites: 1

Brief Summary

Linoleic acid (LA), the predominant omega-6 polyunsaturated fatty acid in human diets, has been associated with improved lipid metabolism and insulin sensitivity compared with saturated fats. However, its role in metabolic health remains debated due to the limited number of well-controlled intervention studies. This randomized controlled trial aims to evaluate the metabolic effects of an LA-rich oil compared with a blended oil in adults with insulin resistance. Participants will be randomly assigned to receive either a daily supplement of LA-rich oil or a control blend oil for 8 weeks, while maintaining their usual diet and lifestyle. The primary outcome is the change in insulin resistance, assessed by the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). Secondary outcomes include changes in fasting glucose, insulin, lipid profile, inflammatory and oxidative stress markers, and body composition. The study is designed as a single-blind, parallel-group intervention conducted at the Pontifical Catholic University of Chile. The results are expected to clarify the effects of increased dietary linoleic acid intake on insulin sensitivity and metabolic risk factors, contributing to the ongoing debate about the role of omega-6 fatty acids in cardiometabolic health.

Conditions

Insulin Resistance; Metabolic Disease

Keywords

linoleic acid; Insulin Resistance; omega-6 fatty acid

Outcome Measures

Primary Outcomes (1)

• Change in insulin resistance (HOMA-IR)

  Insulin resistance will be assessed using the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), calculated from fasting glucose and fasting insulin concentrations. The primary outcome is the change in HOMA-IR from baseline to week 8 between the two study groups.

  Baseline and 8 weeks after the start of the intervention.

Secondary Outcomes (15)

• Glycated hemoglobin (HbA1c)

  Baseline and week 8

• Fasting glucose

  Baseline and week 8

• Fasting insulin

  Baseline and week 8

• Lipid profile

  Baseline and week 8

• Liver enzymes

  Baseline and week 8

Study Arms (2)

Linoleic Acid-Rich Oil

EXPERIMENTAL

Participants in this group will receive a daily supplement of a linoleic acid (LA)-rich oil at a dose of 0.4 mL per kilogram of body weight per day for 8 weeks.

Dietary Supplement: Linoleic Acid-Rich Oil

Blend Oil

ACTIVE COMPARATOR

Participants in this group will receive a daily supplement of a blend oil at 0.4 mL per kilogram of body weight per day for 8 weeks.

Dietary Supplement: Blend Oil

Interventions

Linoleic Acid-Rich Oil DIETARY_SUPPLEMENT

Participants in the experimental group will receive a daily supplement of a linoleic acid (LA)-rich oil at a dose of 0.4 mL per kilogram of body weight per day, taken orally for 8 weeks. The oil is characterized by a high content of omega-6 polyunsaturated fatty acids, primarily linoleic acid (\~60%). To facilitate adherence and appropriate use, participants will receive a recipe booklet encouraging the use of the oil in cold or minimally cooked preparations, or as a topping over foods. They will be instructed to avoid prolonged heating and to store the oil protected from light and at room temperature. The supplement will be provided in identical coded bottles to maintain single-blind conditions. Participants will be asked to maintain their usual diet and lifestyle throughout the intervention.

Linoleic Acid-Rich Oil

Blend Oil DIETARY_SUPPLEMENT

Participants in the control group will receive a daily supplement of a blend oil at a dose of 0.4 mL per kilogram of body weight per day, taken orally for 8 weeks. The blend was formulated to contain approximately equal proportions of saturated, monounsaturated, and polyunsaturated fatty acids, with less than half the linoleic acid content of the LA-rich oil. Participants will receive a recipe booklet promoting the use of the oil in cold dishes or lightly cooked preparations, or as a dressing or drizzle over meals. They will also be instructed on proper storage away from heat and direct light. The supplement will be supplied in identical coded bottles to ensure blinding. Participants will maintain their usual diet and lifestyle during the intervention.

Blend Oil

Eligibility Criteria

• Age: 20 Years - 60 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Men and women aged 20 to 60 years.
• Insulin resistance (HOMA-IR \> 2.6).
• At least one cardiometabolic risk factor: abdominal obesity (waist circumference \> 90 cm in men or \> 80 cm in women); low HDL-cholesterol (\< 40 mg/dL in men or \< 50 mg/dL in women); elevated LDL-cholesterol (\> 70 / 100 / 130 mg/dL, according to estimated cardiovascular risk); or elevated blood pressure (≥ 130/85 mmHg).

You may not qualify if:

• Diabetes diagnosis.
• Severe psychiatric illness.
• Malabsorption disorders or previous bariatric surgery.
• Pregnancy or lactation.
• Previous clinical cardiovascular disease.
• Regular use of medications that could influence study outcomes, including:
• lipid-lowering agents insulin sensitizers antihypertensive drugs anticoagulants antiretroviral therapy thyroid hormones oral corticosteroids immunosuppressants polyunsaturated fatty acid (PUFA) supplements.
• Fasting serum triglycerides ≥ 500 mg/dL or LDL-cholesterol ≥ 190 mg/dL.
• Body mass index (BMI) ≥ 35 kg/m².
• Very high blood pressure.
• Any additional condition that may limit adherence to the study.

Sponsors & Collaborators

• Pontificia Universidad Catolica de Chile: lead

Study Sites (1)

Centro de Investigaciones Clínicas UC (CICUC) - Pontificia Universidad Católica de Chile

Santiago, Santiago Metropolitan, 8330024, Chile

RECRUITING

Related Publications (5)

• Berkowitz L, Echeverria G, Salazar C, Faundez C, Coe CL, Ryff C, Rigotti A. Lipidomic Signature of Healthy Diet Adherence and Its Association with Cardiometabolic Risk in American Adults. Nutrients. 2024 Nov 22;16(23):3995. doi: 10.3390/nu16233995.

  PMID: 39683389 BACKGROUND

• Berkowitz L, Razquin C, Salazar C, Biancardi F, Estruch R, Ros E, Fito M, Corella D, Coe CL, Ryff CD, Ruiz-Canela M, Salas-Salvado J, Wang D, Hu FB, Deik A, Martinez-Gonzalez MA, Rigotti A. Sphingolipid profiling as a biomarker of type 2 diabetes risk: evidence from the MIDUS and PREDIMED studies. Cardiovasc Diabetol. 2024 Dec 18;23(1):446. doi: 10.1186/s12933-024-02505-7.

  PMID: 39695759 BACKGROUND

• Berkowitz L, Mateo C, Salazar C, Samith B, Sara D, Pinto V, Martinez X, Calzada M, von Schultzendorff A, Pedrals N, Bitran M, Echeverria G, Ruini C, Ryff C, Rigotti A. Healthy Eating as Potential Mediator of Inverse Association between Purpose in Life and Waist Circumference: Emerging Evidence from US and Chilean Cohorts. Int J Environ Res Public Health. 2023 Nov 23;20(23):7099. doi: 10.3390/ijerph20237099.

  PMID: 38063529 BACKGROUND

• Calderon M, Plaza G, Gomez M, Samith B, Pinto V, Martinez X, Sara D, Echeverria G, Calzada M, Berkowitz L, von Schultzendorff A, Pedrals N, Bitran M, Rigotti AG. [Limitations and opportunities for the appropriation of the Mediterranean diet in Chilean adults with diagnostic elements of metabolic syndrome]. Nutr Hosp. 2024 Feb 15;41(1):86-95. doi: 10.20960/nh.04652. Spanish.

  PMID: 38047416 BACKGROUND

• Echeverria G, Samith B, von Schultzendorf A, Pinto V, Martinez X, Sara D, Calzada M, Pacheco J, Plaza G, Scott F, Romero J, Mateo C, Julio MV, Utreras-Mendoza Y, Binder MV, Gutierrez F, Riquelme ME, Cuevas M, Willatt R, Sanchez O, Keilendt A, Butron P, Jarufe A, Huete I, Tobar J, Martin S, Alfaro V, Olivos M, Pedrals N, Bitran M, Avalos I, Ruini C, Ryff C, Perez D, Berkowitz L, Rigotti A. Mediterranean diet and psychological well-being intervention to reverse metabolic syndrome in Chile (CHILEMED trial). Contemp Clin Trials Commun. 2023 Jun 26;35:101167. doi: 10.1016/j.conctc.2023.101167. eCollection 2023 Oct.

  PMID: 37538196 BACKGROUND

MeSH Terms

Conditions

Insulin Resistance; Metabolic Diseases

Condition Hierarchy (Ancestors)

Hyperinsulinism; Glucose Metabolism Disorders; Nutritional and Metabolic Diseases

Study Officials

• Loni Berkowitz, PhD

  Pontificia Universidad Catolica de Chile

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Loni Berkowitz, PhD

CONTACT

23543862; lberkowi@uc.cl

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Participants are blinded; both oils are provided in identical coded bottles to maintain masking
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Model Details: Participants will be randomly assigned in a 1:1 ratio to one of two parallel groups: 1. an intervention group receiving a linoleic acid-rich oil, or 2. a control group receiving a blended oil. The study follows a single-blind, parallel-group design lasting 8 weeks.

Study Record Dates

• First Submitted: November 14, 2025
• First Posted: December 17, 2025
• Study Start: May 13, 2025
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): December 1, 2026
• Last Updated: December 17, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

CL (1)