The Effect of Algae Oil Supplements on Functional Immune Response and Bioavailability of Lipids in Blood, a Pilot Study (ALG)

In this explorative study we will investigate whether two sustainable oil supplements yield equivalent results to fish oil supplements in terms of postprandial immune response, among elderly adults, after standardization of the quantity of DHA among the oils. Results on the bioavailability of DHA from different oil supplements will help determine whether differences in DHA bioavailability lead to differences in immune function. Additionally, we will investigate postprandial inflammatory markers. The outcomes of this exploratorive study will provide insight into the variation between individuals and potential effect sizes, and will aim to conduct more targeted follow-up studies on the effects of algae oils on immune function.

Study Overview

• Status: Not yet recruiting
• Conditions: Fatty Acid Metabolism; Functional Immune Response; Postprandial Bioavailability DHA
• Intervention / Treatment: Dietary supplement: Fish oil (control); Dietary supplement: Algae oil 1; Dietary supplement: Algae oil 2

• Study Type: Interventional
• Enrollment (Estimated): 12
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Maartje van den Belt, MSc; Phone Number: 0031618520632; Email: maartje.vandenbelt@wur.nl
• Study Contact Backup: Name: Lonneke Janssen Duijghuijsen, PhD; Phone Number: +31317489390; Email: lonneke.janssenduijghuijsen@wur.nl

Study Locations

• Netherlands
  • Gelderland
    • Wageningen, Gelderland, Netherlands, 6700 AA
      • Wageningen University & Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Apparently healthy men and women;
• Age ≥ 50 years
• Body mass index (BMI) ≥18.5 and ≤30 kg/m2;
• Having veins suitable for blood sampling via a catheter (judged by study nurse/ medical doctor);
• Willing to refrain from fish, fish oil, and products with added omega-3 starting from 2 weeks prior to first postprandial test day.
• Willing to keep a stable dietary pattern throughout the study

Exclusion Criteria:

• Having a disease that may interfere with the outcomes of this study, such as a known metabolic, gastrointestinal, inflammatory or chronic disease (such as anaemia, diabetes, hepatitis, cardiovascular disease), as judged by the medical investigator;
• Having a history of medical or surgical events that may significantly affect the study outcome, including: inflammatory bowel disease, hepatitis, pancreatitis, ulcers, gastrointestinal or rectal bleeding; major gastrointestinal tract surgery such as gastrectomy, gastroenterostomy, or bowel resection; known or suspected gastrointestinal disorders, colon or GI tract cancer;
• Use of medication that may interfere with the study outcomes, including gastric acid inhibitors or laxatives, as judged by the medical supervisor.
• Anaemia (Haemoglobin (Hb) values <7.5 mmol/L for women and <8.5 mmol/L for men), as assessed by finger prick blood during screening visit;
• Having swallowing problems with capsules;
• Allergic for fish or shellfish;
• Recent blood donation (<1 month prior to test day 1 of the study) or not willing to stop donation during and 1 month after the study;
• Average alcohol intake >21 (women) or >28 (men) glasses of alcoholic beverages per week;
• Reported weight loss or weight gain of more than 3 kg in the month prior to pre-study screening, or intention to lose weight during the study period;
• Reported to follow or having planned a slimming or medically prescribed diet;
• Use of drugs;
• Current smokers, or stopped smoking in the last 3 months before study start;
• Insufficient proficiency in Dutch to understand information brochure and questionnaires;
• Participation in any clinical trial including blood sampling and/or administration of sub-stances up to 30 days before test day 1 of this study and during the study period;
• Being an employee of the department Food, Health & Consumer Research Wageningen Food & Biobased Research or Food Quality and Design of Wageningen University.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Fish oil (control); Tuna oil	Dietary supplement: Fish oil (control); Tuna oil
Experimental: Algae oil supplement 1; Algae oil 1	Dietary supplement: Algae oil 1; DHA Origins 550-Y oil (Fermentalg)
Experimental: Algae oil supplement 2; Algae oil 2	Dietary supplement: Algae oil 2; Oleo H-02 (Microalgas)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Functional immune response	Measured in isolated PBMCs by calculating the ratio of pro- and anti-inflammatory markers after ex vivo stimulation with LPS and measurement of the cytokine response. The following markers will be measured: pro inflammatory (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5), anti-inflammatory (IL-4 and IL-10).	Baseline (0 hours)
Functional immune response	Measured in isolated PBMCs by calculating the ratio of pro- and anti-inflammatory markers after ex vivo stimulation with LPS and measurement of the cytokine response. The following markers will be measured: pro inflammatory (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5), anti-inflammatory (IL-4 and IL-10).	4 hours postprandial
Functional immune response	Measured in isolated PBMCs by calculating the ratio of pro- and anti-inflammatory markers after ex vivo stimulation with LPS and measurement of the cytokine response. The following markers will be measured: pro inflammatory (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5), anti-inflammatory (IL-4 and IL-10).	8 hours postprandial
Functional immune response	Measured in isolated PBMCs by calculating the ratio of pro- and anti-inflammatory markers after ex vivo stimulation with LPS and measurement of the cytokine response. The following markers will be measured: pro inflammatory (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5), anti-inflammatory (IL-4 and IL-10).	1 week after exposure to the oil

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	Baseline (0 hours)
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	1 hour postprandial
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	2 hours postprandial
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	3 hours postprandial
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	4 hours postprandial
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	5 hours postprandial
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	6 hours postprandial
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	7 hours postprandial
Plasma DHA levels	Measured in venous blood samples. DHA will be determined by gas chromatography.	8 hours postprandial
Fatty acid levels in plasma and PBMCs	Measured in plasma and PBMCs, fatty acids will be determined by gas chromatography.	Baseline (0 hours)
Fatty acid levels in plasma and PBMCs	Measured in plasma and PBMCs, fatty acids will be determined by gas chromatography.	1 week after exposure to the oil

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	Baseline (0 hours)
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	1 hour postprandial
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	2 hours postprandial
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	3 hours postprandial
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	4 hours postprandial
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	5 hours postprandial
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	6 hours postprandial
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	7 hours postprandial
Plasma EPA levels	Measured in venous blood samples. Plasma EPA will be determined by gas chromatography	8 hours postprandial
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	Baseline
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	1 hour postprandial
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	2 hours postprandial
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	3 hours postprandial
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	4 hours postprandial
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	5 hours postprandial
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	6 hours postprandial
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	7 hours postprandial
Functional immune response in plasma	The ratio of pro (PGE2, IL-1β, IL-6, IL-8, IFNg, TNFα, CCL2 and CCL5) and anti-inflammatory markers (IL-4 and IL-10) will be determined using ELISA kits or a custom LegendPlex.	8 hours postprandial
Oxylipin levels in plasma	Oxylipin levels will be determined by LC-MS/MS after solid phase extraction	Baseline (0 hours)
Oxylipin levels in plasma	Oxylipin levels will be determined by LC-MS/MS after solid phase extraction	4 hours postprandial
Oxylipin levels in plasma	Oxylipin levels will be determined by LC-MS/MS after solid phase extraction	8 hours postprandial
Oxylipin levels in plasma	Oxylipin levels will be determined by LC-MS/MS after solid phase extraction	1 week after exposure to the oil
Fatty acid levels in cell membranes of erythrocytes	Fatty acid levels in cell membranes of erythrocytes will be determined by gas chromatography	Baseline (0 hours)
Fatty acid levels in cell membranes of erythrocytes	Fatty acid levels in cell membranes of erythrocytes will be determined by gas chromatography	1 week after exposure to the oil
Gastrointestinal complaints	Abdominal pain, bloating, flatulence, gastric acid, nausea, diarrhea on a VAS scale (0-10)	Baseline (0 hours)
Gastrointestinal complaints	Abdominal pain, bloating, flatulence, gastric acid, nausea, diarrhea on a VAS scale (0-10)	4 hours postprandial
Gastrointestinal complaints	Abdominal pain, bloating, flatulence, gastric acid, nausea, diarrhea on a VAS scale (0-10)	8 hours postprandial
Gastrointestinal complaints	Abdominal pain, bloating, flatulence, gastric acid, nausea, diarrhea on a VAS scale (0-10)	12 hours postprandial
Gastrointestinal complaints	Abdominal pain, bloating, flatulence, gastric acid, nausea, diarrhea on a VAS scale (0-10)	1 week after exposure to the oil
Short term well-being	Short-term well-being assessed by the Multidimensional Mood Questionnaire (MDMQ)	Baseline (0 hours)
Short term well-being	Short-term well-being assessed by the Multidimensional Mood Questionnaire (MDMQ)	4 hours postprandial
Short term well-being	Short-term well-being assessed by the Multidimensional Mood Questionnaire (MDMQ)	8 hours postprandial
Short term well-being	Short-term well-being assessed by the Multidimensional Mood Questionnaire (MDMQ)	12 hours postprandial
Short term well-being	Short-term well-being assessed by the Multidimensional Mood Questionnaire (MDMQ)	1 week after exposure to the oil

Collaborators and Investigators

• Sponsor: Maartje van den Belt
• Collaborators: Utrecht University; Nutricia Research; Fermentalg; Microalgas Oleas de México, S.A. de C.V.
• Investigators: Principal Investigator: Maartje van den Belt, MSc, Wageningen Food and Biobased Research

Study record dates

Study Major Dates

• Study Start (Estimated): September 22, 2025
• Primary Completion (Estimated): November 14, 2025
• Study Completion (Estimated): November 14, 2025

Study Registration Dates

• First Submitted: July 17, 2025
• First Submitted That Met QC Criteria: July 17, 2025
• First Posted (Actual): July 25, 2025

Study Record Updates

• Last Update Posted (Actual): July 25, 2025
• Last Update Submitted That Met QC Criteria: July 17, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: Omega-3; Immune function; DHA bioavailability; ALG study; Algae oil
• Other Study ID Numbers: 2023-16979

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Since study participants did not give consent to share data with other parties.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No