A Study on the Possible Health Effects of Lean Fish and Fatty Fish Intake in Overweight or Obese Adults

Study Overview
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Brief Summary
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The potential health effects of high intake of lean or fatty fish will be investigated in overweight or obese adults. Participants consume 750g/week of fillets of fish for 8 weeks. Hypothesis: High intake of fatty or lean fish will beneficially affect glucose regulation and the immune system.

Official Title
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Fiskespisestudiene 2011-2014. Spiseforsøk Med Fisk. Delstudie 2: Studie av Mulige Effekter av Fet og Mager Fisk på Glukosemetabolismen og inflammasjonsmarkører i Overvektige Voksne.

Conditions
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Overweight, Obesity

Intervention / Treatment
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* Other: Lean fish
* Other: Fatty fish


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI ≥27 kg/m2 fasting blood glucose ≤7.0 mmol/L Exclusion Criteria: pregnancy incompatibility with fish consumption (allergies, intolerance and/or dislike) diagnosed diabetes mellitus, heart disease or gastrointestinal diseases use of medications affecting lipid metabolism or glucose homeostasis use of anti-inflammatory medications use of supplements containing long chain n-3 fatty acids intentional weight loss and large fluctuation in body weight (>3 kg) over the previous two months

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 69 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Lean fish<br>Participants eat 750g of lean fish per week for 8 weeks. | Other: Lean fish<br> <br> |
| Experimental: Fatty fish<br>Participants eat 750g of fatty fish per week for 8 weeks. | Other: Fatty fish<br> <br> |
| No Intervention: Control<br>Participants eat as normal, but avoid fish and seafood for 8 weeks. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in serum concentrations of glucose |  | baseline and 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in insulin, insulin C-peptide, leukocyte fatty acids, leukocyte function, body weight and composition, and intake of energy and macronutrients within the groups over time. |  | baseline and 8 weeks | 
| Changes in serum vitamin concentrations after fish intake. | Serum concentrations of fat-soluble and water-soluble vitamins were measured, and dietary intakes of vitamins were estimated based on reported food intake from 5-day food diaries. | baseline and 8 weeks | 
| Changes in serum and urine concentrations of amino acids and metabolites of amino acids after fish intake. | Concentrations of amino acids and amino acid metabolites were measured in fasting serum and morning urine | baseline and 8 weeks | 
| Changes in fecal microbiota profile after fish intake. | 54 DNA bacterial markers targeting more than 300 bacteria based on their 16S rRNA sequence in seven variable regions were analysed in feces (72h collection) | baseline and 8 weeks | 
| Changes in fecal and serum concentrations of lipids and bile acids after fish intake. | Fat, cholesterol and total bile acids were quantified in feces (72h collection) and fasting serum. | baseline and 8 weeks | 
| Changes in markers of oxidative stress after fish intake. | Antioxidant enzymes, antioxidant enzyme cofactors and biomarkers of oxidative stress were quantified in serum | baseline and 8 weeks | 
| Changes in total neopterin after fish intake | Total neopterin was measured in serum. | baseline and 8 weeks | 
| Quantification of markers of kidney dysfunction | Urine concentrations of cystatin C and T-cell immunoglobulin mucin-1 (relative to creatinine) were measured as markers of kidney function | baseline and 8 weeks | 
| Changes in amino acids and metabolites of amino acids after a standardized meal. | Concentrations of amino acids and amino acid metabolites were measured in fasting and postprandial serum | baseline | 
| Changes in metabolites and co-factors involved in one-carbon metabolism after a standardized meal | Concentrations of relevant metabolites and co-factors were measured in fasting and postprandial serum | baseline | 
| Comparisons of amino acid concentrations in serum and urine between men and women | Concentrations of amino acids and amino acid metabolites were measured in serum and urine | baseline | 
| Comparisons of metabolites and co-factors involved in one-carbon metabolism in serum and urine between men and women | Concentrations of relevant metabolites and co-factors were measured in serum and urine | baseline |