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Seaweed

Bladderwrack

Also known as: Fucus vesiculosus, Kelp, Rockweed, Black tang

C
Evidence

Iodine-rich seaweed traditionally used for thyroid support, but dose is highly variable.

Primary uses

  • Natural iodine source
  • Thyroid support (traditional)
  • Metabolic support

How it works

  • Natural iodine source
  • Also contains fucoidan
  • Traditional thyroid remedy
  • Variable iodine makes dosing difficult

Dosage

Typical range
Varies widely - often 500-1000mg providing variable iodine
Timing
Morning
With food
Either way
Duration
Monitor thyroid if using long-term
Special populations
Those seeking natural iodine source

Forms

  • Capsules
  • Tincture
  • Dried

Safety

Common side effects

  • GI upset
  • Metallic taste
  • Acne

Contraindications

  • Hyperthyroidism
  • Hashimoto's (variable)
  • Heavy metal sensitivity

Evidence notes

Variable iodine content makes dosing unreliable

Grade C: Mostly observational or small trials; mechanism is plausible but unproven at scale.

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.