The Claim

A 5-gram dry portion of most Scottish seaweed species contains iodine concentrations exceeding the European Tolerable Upper Limit of 600 μg/day, with Laminaria digitata exhibiting a concentration of 1455 ± 181 mg/kg dry weight, resulting in a risk of excessive iodine intake even with weekly consumption.

Source: Scottish Seaweeds as Sustainable Sources of Micronutrients: Mineral Composition, Vitamin B12 Content, and Safety Assessment

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
44score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Quantitative
1 study reviewed
In plain English

Eating a 5-gram serving of most Scottish seaweed provides more iodine than the European safety limit of 600 micrograms per day, and one common species, Laminaria digitata, contains over 1,400 milligrams of iodine per kilogram of dry weight, which can lead to iodine intake above safe levels even when consumed once a week.

See the scientific wording

A 5-gram dry portion of most Scottish seaweed species contains iodine levels exceeding the European Tolerable Upper Limit of 600 μg/day, with Laminaria digitata reaching 1455 ± 181 mg/kg dry weight, posing a potential risk of excessive iodine intake even with weekly consumption.

Why this might work

Eating too much iodine from seaweed overwhelms the thyroid gland, causing it to temporarily stop making thyroid hormones. This shutdown can lead to low hormone levels, which then triggers the brain to overstimulate the thyroid, potentially causing swelling or long-term dysfunction.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Scottish Seaweeds as Sustainable Sources of Micronutrients: Mineral Composition, Vitamin B12 Content, and Safety Assessment

    This study found that just a tiny spoonful of most Scottish seaweed has way more iodine than you should eat in a whole day—even if you only eat it once a week. That means it could hurt your thyroid if you’re not careful.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.