Seaweed Iodine Delivered Via Food or Supplementation
Condition: Iodine Deficiency
Study type: Interventional

Summary: 
      In this project, the investigators propose an intervention design testing the efficacy of a
      food reformulated with seaweed as an ingredient in meal, capsules against placebo and no
      intervention controls. The randomised control trial (supplementation) will last 24 weeks. The
      aim is to study the effect of the food matrix on variables associated with iodine nutrition:
      iodine status and thyroid function.
    

Detailed description: 
      This study is a randomized, double-blind, placebo-controlled trial conducted in Glasgow,
      United Kingdom. Inclusion criteria are as follows: healthy premenopausal women aged 18 - 60
      years who would remain a resident in Glasgow for 24 weeks; who were self-reported low iodine
      consumers consuming milk less than once per day and non-oily fish less than once per week.
      Those with a history of thyroid dysfunction, taking medications other than the contraceptive
      pill or smoking, as well as pregnant or lactating women and those planning to conceive, were
      excluded. Those taking dietary supplements containing iodine would also excluded and there
      was no restriction related to body mass index (BMI).

      Participants are recruited via social media and advertisements displayed around the Greater
      Glasgow area. Interested parties are screened and, if eligible, invited to a 30-minute
      appointment at which participants were randomly assigned through a web-based randomisation
      service to one of four groups after consent is obtained; reformulated pizza, control pizza,
      iodine capsules, or placebo capsules. During this initial meeting anthropometric
      measurements, blood pressure and a venous blood sample are collected, and participants are
      also asked to complete a sociodemographic questionnaire and an iodine specific food frequency
      questionnaire (FFQ). Participants are provided with instructions and equipment to record a
      3-day estimated food diary and to collect 12 spot urine samples at different times of day
      over 2-7 days. Upon returning the spot urine samples, participants were given either the
      pizzas or supplements to begin the intervention. Participants are asked to consume one pizza
      or supplement three times a week for 24 weeks. Participants are asked to collect a further
      10-12 sample spot urine samples at week 2 of the intervention. Participants are asked to
      attend another 30-minute appointment at 12 and 24 weeks in which baseline measurements are
      repeated along with a change to diet questionnaire.
    

Intervention name(s): Reformulated pizza; Control pizza; Seaweed capsule; Control capsule
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): Reformulated food with 400ug of iodine per meal, three times per week (to achieve 122% of weekly recommended intakes - average 140ug/day).; Control (placebo) meal to consume thrice weekly (no iodine supplementation).; Capsules containing seaweed extract, the iodine-rich ingredient in the reformulated pizza, 400ug iodine per capsule, to be consumed three times per week (122% of weekly recommended intake).; Empty capsules (placebo)
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Randomized, double-blind, placebo-controlled trial
Masking: Double (Participant, Investigator)
Primary purpose: Other
Keywords: iodine; seaweed; supplementation; reformulation; food matrix; thyroid function