Macroalgae Consumption - a Pilot Study

Study Overview
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Brief Summary
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In this study, the aim is to investigate the food safety of macroalgae. There will be an analysis of macroalgae products for the concentration of cadmium, inorganic arsenic, and iodine in macroalgae, as well as measure the status of these elements in consumers. An investigation of the thyroid function of macroalgae consumers and the use of metabolomics to explore which biological changes occur when consuming seaweed and kelp and when the consumer excludes macroalgae from their diet will be performed.

Detailed Description
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A group of consumers of macroalgae will be recruited to investigate their macroalgae intake and iodine, cadmium, and inorganic arsenic status and thyroid function. Iodine, cadmium, and inorganic arsenic have been selected since these elements have been described as relatively high in a previously published report from Norway. The goal is to recruit consumers of brown algae - especially kelp, and certain types of red algae, as these were the species with the highest content of iodine, cadmium, and arsenic, described in a previous publication. The participants will be asked to abstain from macroalgae for 6 weeks and again examine iodine status, cadmium and arsenic exposure, and thyroid function after the cessation period. A withdrawal period of 6 weeks has been chosen on the basis that it is calculated 6-8 weeks after Levaxin treatment for hypothyroidism before a new equilibrium can be expected and the effect of treatment on TSH can be assessed. This study will provide new insight into the status of iodine, cadmium, and inorganic arsenic that macroalgae consumers have in urine and thyroid function after regular macroalgae consumption and after cessation of macroalgae intake. In addition, the study will provide descriptive data on macroalgae consumption, how it is eaten, how often, and how much. This can provide critical knowledge to the national and European authorities for food safety and public health advisers to evaluate the food safety of macroalgae.

Official Title
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Macroalgae Consumption - a Pilot Study

Conditions
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Iodine Toxicity

Intervention / Treatment
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* Other: Habitual macroalgae consumption
* Other: No macroalgae consumption


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adults weekly consumer of macroalgae Exclusion Criteria: pregnant known disease

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Other
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Usual macroalgae consumption<br>Crossover design with habitual macroalgae consumption at baseline | Other: Habitual macroalgae consumption<br>* The participant have a habitual macroalgae consumption at baseline.<br>Other: No macroalgae consumption<br>* The participants exclude any macroalgae products from their diet<br>|
| Experimental: Cessation of macroalgae consumption<br>Cessation of macroalgae consumption as an experimental intervention. | Other: Habitual macroalgae consumption<br>* The participant have a habitual macroalgae consumption at baseline.<br>Other: No macroalgae consumption<br>* The participants exclude any macroalgae products from their diet<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Consumption of macroalgae products | Assess the dietary consumption of macroalgae in consumers in the Bergen and Oslo area by 24hr recall and food frequency questionnaire | Through study completion, on average 6 weeks | 
| Levels of iodine, cadmium and inorganic arsenic in macroalgae products | Analyse the levels of iodine, cadmium and inorganic arsenic in macroalgae products used by the participants | Through study completion, on average 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Levels of iodine | Analyse the levels of iodine in urine after intervention/usual macroalgae consumption | 6 weeks | 
| Levels of cadmium in urine | Analyse the levels of cadmium urine after intervention/usual macroalgae consumption | 6 weeks | 
| Levels of inorganic arsenic in urine | Analyse the levels of inorganic arsenic in urine after intervention/usual macroalgae consumption | 6 weeks | 
| Levels of creatinine in urine | Analyse the of creatinine in urine after intervention/usual macroalgae consumption | 6 weeks | 
| Thyroid function measure by thyroid-stimulating hormon | Measurement of thyroid-stimulating hormon (TSH) in serum after intervention/usual macroalgae consumption | 6 weeks | 
| Thyroid function measure by ree-triiodinetyronin | Measurement of free-triiodinetyronin (fT3) in serum after intervention/usual macroalgae consumption | 6 weeks | 
| Thyroid function measure by free thyroxine | Measurement of free thyroxine (fT4) in serum after intervention/usual macroalgae consumption | 6 weeks | 
| Thyroid function measure by Thyroid peroxidase antibody | Measurement of Thyroid peroxidase antibody (TPOAb) in serum after intervention/usual macroalgae consumption | 6 weeks | 
| Thyroid function measured by thyroglobulin | Measurement of thyroglobulin (Tg) in serum after intervention/usual macroalgae consumption | 6 weeks | 
| Thyroid function | Measurement of thyroid-stimulating hormon (TSH), free-triiodinetyronin (fT3), free thyroxine (fT4), Thyroid peroxidase antibody (TPOAb), thyroglobulin (Tg) in serum after intervention/usual macroalgae consumption | 6 weeks | 
| Metabolic changes | Measurement of metabolic changes by non-targeted metabolomics after intervention/usual macroalage consumption | 6 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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macroalgae, iodine, consumption