The World Health Organization recommends monitoring iodine status in all populations with median urinary iodine concentration below 100 µg/L suggesting iodine deficiency. There are no data on the iodine intake among the population of the Faroe Islands. This study aimed to provide data on iodine nutrition in a representative sample of the general adult population from the Faroe Islands. We conducted a population-based cross-sectional survey in 2011-2012 and measured iodine in urine from 491 participants (294/197 men/women) using the ceri/arsen method after alkaline ashing. Participants include around 100 subjects in each of four adult decades and included participants from both the capital city and villages. The median urinary iodine concentration was low within the recommended range 101 µg/L (range 21-1870 µg/L). No samples were in the range suggesting severe iodine deficiency, but half of the samples were in the range of just adequate or mildly insufficient iodine intake with urinary iodine concentration markedly lower in women than in men (86 versus 115 µg/L; P<0·001). Intake of fish and whale meals affected the urinary iodine concentrations. In conclusion, nearly half of the population had an iodine excretion in the range of borderline or mild iodine deficiency. The lowest iodine nutrition level among Faroese women is a concern as it may extend to pregnancy with increased demands on iodine nutrition. In addition, we found large variations and the intermittently excessive iodine intakes warrants follow-up on thyroid function in the population of the Faroe Islands.

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Iodine nutrition is critical for human health. While iodine excretion was low within the recommended range among adult Faroese, younger generations tend to abandon local foods. Such changes raise a concern about iodine intake, which led us to perform this first study of iodine nutrition among teenagers in the North Atlantic islands. We used samples from a nationwide collection of urine samples in 14-year-olds following iodine fortification of salt in 2000. Urine was analysed for iodine and creatinine to adjust for dilution by iodine/creatinine, and a food frequency questionnaire was used to record the intake of iodine-rich foods. The 129 participants yielded a 90 % precision of the estimated iodine nutrition level. The median urinary iodine concentration (UIC) was 166 μg/l (bootstrapped 95 % confidence interval 156–184 μg/l). The median creatinine-adjusted UIC was 132 μg/g (bootstrapped 95 % CI 120–138 μg/g). Fish and whale meat dinners were more frequent among residents of villages compared with the capital: median fish dinners, 3 v. 2 per week (P = 0⋅001), and whale meat, 1 v. 0⋅4 per month (P < 0⋅001). UIC decreased with fewer fish dinners (P = 0⋅03). Our study demonstrated that Faroese teenagers were iodine-replete. The changing dietary habits emphasise the need for continuous monitoring of iodine nutrition and surveying iodine deficiency disorders.

Background and aims: Autoimmune liver diseases are rare diseases, and population-based studies on the epidemiology of autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) are sparse. We aimed to assess the incidence of AIH, PBC, and PSC in the Faroe Islands. Methods: All cases of AIH, PBC, and PSC diagnosed in the Faroe Islands between January 1 st , 2004, and December 31 st , 2021, were included in this nationwide registry-based cohort study. In addition, we searched all medical records to assess diagnostic criteria and cause of death. Results: The incidences of AIH, PBC, and PSC in the Faroe Islands were 5.2, 2.5 and 0.7 per 100,000 population per year, respectively. Point prevalence per 100,000 population on December 31st 2021, was 71.8 for AIH, 38.5 for PBC, and 11.0 for PSC. Nine AIH patients died after a median of 3 years, three died of hepatocellular carcinoma (HCC), and two died of liver failure. Five PBC patients died after a median of 7 years, one of HCC and one of liver failure. One PSC patient died of cholangiocarcinoma. Conclusion: The incidence and prevalence of AIH, PBC and PSC in the Faroe Islands are among the highest reported in population-based settings.

Iodine is essential for human health, and dietary iodine sources are critical. Living isolated on islands in the North Atlantic Ocean fostered unique dietary traditions in the Faroe Islands. The dietary peculiarities led us to collect and measure the iodine content of local foods and beverages and calculate daily iodine intakes based on four Faroese dietary scenarios. Marine foods and birds had iodine contents from 300 µg/kg and up, markedly higher than dairy, grains, terrestrial, vegetables, and liquid foods ( p <0.001). Vegetables and beverages contained negligible iodine. Wind-dried fermented lamb meat iodine content varied by 100% depending on whether it was herded on an island with beaches (105 µg/kg) or with cliffs (53 µg/kg) facing the ocean. The daily iodine intake varied from around 50 µg to just over 200 µg with diets rich in fish and whales. In conclusion, the traditional diet has been a critical source of iodine on the Faroe Islands. The Faroese may be iodine replete with traditional diets but face the risk of iodine deficiency with dietary transition towards a more western diet. Locally produced Faroese foods are therefore relevant to promote health, and may additionally support food security, local involvement and knowledge, and long-term sustainability.