The Influence of Fish Consumption on Polyunsaturated Fatty Acid (PUFA) Status (iFish)

The Influence of Fish Consumption on Polyunsaturated Fatty Acid (PUFA) Status (iFish Study)

Polyunsaturated fatty acids (PUFA) are important for health, for example for the immune system, heart health and the brain. PUFA are found in fish, nuts and oils; including these foods in the diet provides the body with PUFA. The body can also produce some PUFA in a series of steps. It has been found that genetics influences the levels of PUFA produced in the body. This study will investigate whether fish consumption influences PUFA status in women of childbearing age when accounting for FADS genotype by conducting a controlled human intervention study. Participants will be asked to consume none, one or two portions of oily fish per week for 8 weeks and their response in PUFA status measured. This study will also use collected blood, hair, urine and faecal samples collected from the intervention study to explore other biomarkers of fish consumption. The aim of this study is to investigate whether fish consumption influences PUFA status in women of childbearing age when accounting for FADS genotype and to explore the potential of a novel biomarker, using hair MeHg:δ34S values, to accurately predict fish consumption. The study will initially involve providing a buccal swab sample which will investigate genes which are related to fatty acids. The participant will provide a buccal swab sample so that their genotype can be determined. The researcher who will contact the participant once genotype has been determined to arrange a baseline appointment. Participants will attend the Human Intervention Studies Unit at Ulster University, Coleraine once or twice weekly for a period of 8 weeks where they will receive lunch. This lunch will contain either tuna, sardines, or no fish depending on the intervention group you will be allocated to. Examples of lunch time meals they may receive include sandwiches, baked potato or salad which will include the type of fish they have been allocated to receive. Those allocated to the no fish group will receive a fish free alternative lunch. Participants will be asked to continue to follow their normal diet and lifestyle over the intervention period of 8 weeks. All participants will attend a baseline and post intervention appointment where they will have weight, height and body composition measured. Participants will also complete questionnaires to provide medical, lifestyle and dietary information. All participants will be asked to provide a sample of blood, urine, hair and faeces to assess biomarkers of fish consumption at baseline and post intervention appointments. Collected blood, urine, hair and faecal samples will be analysed for biomarkers of fish consumption. Participants will also be asked to return to the Human Intervention Studies Unit (HISU) 8 weeks after the intervention study has been completed (week 16) to provide a third hair sample and complete a Fish Feedback Questionnaire. In the 8 wks following conclusion of the study they will be free to return to their normal diet.

Study Overview

• Status: Completed
• Conditions: Polyunsaturated Fatty Acid (PUFA) Status
• Intervention / Treatment: Other: Control; Dietary supplement: Fish

• Study Type: Interventional
• Enrollment (Actual): 49
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Co.Londonderry
    • Coleraine, Co.Londonderry, United Kingdom, BT52 1SA
      • Human Intervention Studies Unit, Ulster University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years to 41 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Healthy females - premenopausal, child-bearing age, not planning to become pregnant
• Age 18-45years old
• Low consumers of fish (<2 portions/ week) or those willing to reduce their fish consumption one month prior to commencing the study to the equivalent of 2 portions per month or less
• Willing to eat 1 or 2 portions (140 grams or 280 grams) of either tuna or sardines per week for a period of 8 weeks
• Not consuming fish oil supplements
• Not consuming protein supplements
• Not allergic to seafood

Exclusion Criteria:

• Regularly eat fish or not willing to do washout period where they reduce fish consumption
• Are allergic to seafood
• Are taking fish oil supplements or are taking protein supplements
• Are pregnant or menopausal
• Have very short hair (a small section of hair, approximately 200 strands, will be taken at the nap of the neck for analysis purposes)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Control group; No fish	Other: Control; Lunch containing no fish
Experimental: 1 portion of fish per week; 140g fish/week	Dietary supplement: Fish; Lunch containing fish
Experimental: 2 portions of fish per week; 280g fish/week	Dietary supplement: Fish; Lunch containing fish

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Polyunsaturated fatty acid (PUFA) status	Serum Polyunsaturated fatty acid (PUFA) status	Change at 8 weeks from baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hair mercury	Hair mercury status	Change at 8 & 16 weeks from baseline
Lipid profile	Serum lipid profile	Change at 8 weeks from baseline
Iodine	Urine iodine	Change at 8 weeks from baseline
Inflammatory status	Cytokine concentration (Interleukin (IL)-5, IL-1β, IL-2, IL-4, IL-6, IL-10, MCP-1, TARC, sFlt-1, VEgF-D, CRP, TNF-α, IFN-γ)	Change at 8 weeks from baseline
Oxidative stress	Change in glutathione peroxidase and 8-isoprostanes	Change at 8 weeks from baseline
Microbiota	Faecal microbiota profile	Change at 8 weeks from baseline
Thyroid hormones	Serum T3, T4 and thyroid-stimulating hormone (TSH). Dried blood spot for thyroglobulin, T4 and TSH	Change at 8 weeks from baseline
Stable isotopes	Hair methyl-mercury and sulphur-34	Change at 8 & 16 weeks from baseline
Methyl-mercury (MeHg)	Whole blood and urine MeHg	Change at 8 weeks from baseline

Collaborators and Investigators

• Sponsor: University of Ulster
• Collaborators: Lund University; University of Rochester; Ministry of Health, Republic of Seychelles

Publications and helpful links

General Publications

• Conway MC, McSorley EM, Mulhern MS, Spence T, Wijngaarden EV, Watson GE, Wahlberg K, Pineda D, Broberg K, Hyland BW, Cobice DF, Strain JJ, Yeates AJ. The influence of fish consumption on serum n-3 polyunsaturated fatty acid (PUFA) concentrations in women of childbearing age: a randomised controlled trial (the iFish Study). Eur J Nutr. 2021 Apr;60(3):1415-1427. doi: 10.1007/s00394-020-02326-w. Epub 2020 Jul 28.

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2016
• Primary Completion (Actual): May 31, 2017
• Study Completion (Actual): May 31, 2017

Study Registration Dates

• First Submitted: December 4, 2018
• First Submitted That Met QC Criteria: December 4, 2018
• First Posted (Actual): December 5, 2018

Study Record Updates

• Last Update Posted (Actual): December 5, 2018
• Last Update Submitted That Met QC Criteria: December 4, 2018
• Last Verified: December 1, 2018

More Information

Terms related to this study

• Keywords: women; fish; childbearing age; Polyunsaturated fatty acids (PUFA); fish consumption
• Other Study ID Numbers: REC/16/0077

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No