An interventional study of Omega-3 and HOSO in Overweight and Hypertriglyceridemia, sponsored by Universidad San Sebastián. Completed at 1 site in Chile. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-09-25.
Sponsored by Universidad San Sebastián · Not applicable, Interventional, and Prevention
The RIO-Study project is a randomized, controlled, double-blind, crossover trial aimed at determining the effectiveness of omega-3 fatty acids at nutritional doses on lipid metabolism and inflammation in overweight and obese individuals with hypertriglyceridemia in Chile.
The study will include 40 participants (each participant will serve as their own control) aged 18-65, with 25-34.9 kg/m2 BMI and fasting triglycerides (TG) of 100-215 mg/dL. The intervention consists of 250 mg EPA from algae oil versus high oleic sunflower oil (HOSO) for 6 weeks each, after a 10-week washout period, the treatments will be switched for another 6 weeks, considering four visits during the whole study. The main outcomes to be evaluated are serum triglyceride levels, expression of target genes in peripheral blood mononuclear cells (PBMCs), low-grade inflammation biomarkers, and very low-density lipoprotein (VLDL) atherogenic properties. The study also analyzes background diet, chrononutrition, and physical activity aspects. Results are expected to provide new insights into the effects of nutritional doses of omega-3 in the Chilean population, particularly on fasting and postprandial triglyceride metabolism and cardiovascular disease risk reduction.
Before and after each intervention period, fasting blood samples will be collected. On each visit day, participants will consume a standardized breakfast (three slices of white bread with butter and jam), and postprandial blood samples will be taken at 0, 2, 4, and 6 hours to measure triglycerides and other lipid parameters.
The study will assess:
The study will collaborate with international partners for specialized analyses, including gene expression studies and VLDL atherogenic properties assessment.
This comprehensive approach aims to provide new insights into the effects of nutritional doses of omega-3 fatty acids on lipid metabolism and inflammation in the Chilean population, with a particular focus on postprandial triglyceride metabolism and cardiovascular disease risk reduction.
3,670 studies on the registry are indexed under Overweight; 849 are open to participants now.
This study's enrollment of 40 is below the median of 73 across 3,175 interventional studies indexed under Overweight.
Browse Overweight studies →Universidad San Sebastián is the lead sponsor of 13 studies on the registry; 5 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Participants will be randomized to either star to receive a capsule/day with omega-3 fatty acid from 1g Nannochloropsis sp. microalga (250 mg of EPA) for 6 weeks. Followed by a wash-out period of 10 weeks.
Dietary Supplement: Omega-3
Participants will be randomized to either star to receive a placebo capsule/day with the same weight of high oleic sunflower oil -HOSO (with no EPA or other omega-3 fatty acid content), for 6 weeks. Followed by a wash-out period of 10 weeks.
Dietary Supplement: HOSO
Dietary Supplement: Omega-3 In the marine Omega-3 fatty acid period, the participants will receive a capsule with 250 mg of EPA per day during 6 weeks.
Dietary Supplement: HOSO In the HOSO period, the participants will receive a capsule with the similar weight of HOSO per day during 6 weeks.
Fasting TG (mg/dL)
Baseline serum levels of circulating triglycerides
Time frame: up to 6 weeks
Postprandial TG (mg/dL)
Triglyceride concentration (mg/dL) measured by enzymatic colorimetric assay at baseline (fasting) and at 2, 4, and 6 hours after consumption of a standardized 50 g fat meal.
Time frame: up to 6 weeks
Change in mRNA expression levels of lipid metabolism genes in Peripheral Blood Mononuclear Cells (PBMCs)
Fold change in mRNA expression of genes of lipid metabolism in PBMCs at 0h and 4h, measured by RT-qPCR
Time frame: up to 6 weeks
Change in concentrations (pg/mL) of pro-inflammatory cytokines TNF-α and IL-6
Serum concentrations (pg/mL) of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) measured by enzyme-linked immunosorbent assay (ELISA) at fasting (0h) and 4 hours postprandial following a standardized test meal
Time frame: up to 6 weeks
Fasting serum Low-Density Lipoproteins, High-Density Lipoproteins, Very Low-Density Lipoproteins (mg/dL)
Fasting levels before and after intake of omega-3 or HOSO
Time frame: up to 6 weeks
Fasting plasma glucose concentration (mg/dL)
Fasting levels before and after intake of omega-3 or HOSO
Time frame: up to 6 weeks
This study is completed, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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Universidad San Sebastián