We use essential cookies (authentication, your saved goals/stack) by default. With your permission we’ll also enable privacy-respecting analytics (Vercel Web Analytics, anonymous load-time metrics) and error-replay diagnostics (Sentry — DOM snapshots only when an error fires) so we can fix bugs faster. Learn more about cookies
Klp3.0
Kelp Research
Mostly mechanism / observational
19 peer-reviewed studies
What the evidence says
Mostly mechanism / observational
Most Kelp studies are mechanism or observational rather than RCTs that measure a clinical effect — keep findings provisional.
Most evidence is from high-quality randomised trials published 2003–2026 with a typical study size of 1 participants.
Based on 19 studies · 12 RCTs · 46 total participants
Confidence
Moderate confidence
By outcome
Glucose & metabolicProvides iodine needed for thyroid hormone synthesis — but only relevant in iodine deficiency, and the dose is unpredictable · Unknown
Too few graded studies2 studies
Active research area
6 studies in the last 5 years
200320142026
1Systematic Review2022
Lee IS, Ko SJ, Lee YN, Lee G, Rahman H, Kim B · Nutrients (2022)
In plain English: Population-based solutions would correct iodine status efficiently and align the UK with other high-income countries.
Taylor PN, Prentice M, Bath S, Combet E, Schoenmakers N, Smith VE, Gibb FW, Zammitt N, Okosieme O, Boelaert K, Lazarus J, Vanderpump M. · Clinical endocrinology (2026)
Endocrinologists now face a dual challenge: widespread under-recognition of population iodine insufficiency and a growing minority of patients presenting with iodine-induced thyroid dysfunction.
This review summarises current UK iodine status, the physiological and clinical relevance of iodine to thyroid and neurodevelopmental health, modern dietary risk factors and the clinical approach to those influenced by online misinformation.
Routine dietary counselling and public health fortification represent cost-effective interventions to prevent both extremes.
In plain English: This review comprehensively examines current advancements in fucoidan extraction and purification techniques, discusses its structural characterization, and synthesizes recent findings on its multifaceted biological activities to explore its potential and significance in human health.
Wan H, Zhang YX, Gao ZC, Shan GY, Liu F, Li HJ. · International journal of biological macromolecules (2025)
Laminaria japonica (L. japonica), a widely cultivated marine macroalga, has gained substantial attention in human nutrition due to its rich composition of carbohydrates, essential minerals, and vitamins.
Despite these recognized benefits, systematic reviews addressing the extraction and purification methodologies, structural elucidation, compositional analysis, and associated bioactivities of L. japonica-derived fucoidan remain limited.
In plain English: This study found excessive iodine status in macroalgae consumers, and consumers should be made aware of the risk associated with including seaweed in their diet.
Aakre I, Tveito Evensen L, Kjellevold M, et al. · Nutrients (2020)
Median urinary iodine concentration was 1200 ug/L — far above the adequate range, indicating excessive iodine exposure
Seaweed was the major contributor to iodine intake among consumers
TSH levels, while within reference range, were higher than in comparable population groups
In plain English: Eight of nine randomly obtained commercial kelp samples showed arsenic above the FDA tolerance level, and a patient's symptoms resolved after discontinuing her kelp supplement.
Amster E, Tiwary A, Schenker MB. · Environ Health Perspect (2007)
A woman with alopecia, memory loss and fatigue had elevated urinary arsenic; her kelp supplement contained 8.5 mg/kg arsenic
Symptoms resolved within weeks of stopping the supplement
8 of 9 randomly sampled commercial kelp products exceeded FDA arsenic tolerance levels
In plain English: Physicians should advise patients with underlying thyroid disease to avoid all complementary or alternative medications containing iodine.
Müssig K, Thamer C, Bares R, Lipp HP, Häring HU, Gallwitz B. · J Gen Intern Med (2006)
A 39-year-old woman with multinodular goiter developed iodine-induced hyperthyroidism after 4 weeks of kelp-containing tea
Thyrotoxicosis resolved after stopping the kelp and starting antithyroid therapy
Demonstrates real thyroid risk of kelp iodine in susceptible people