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Mineral

Kelp

Also known as: Sea Kelp, Kelp Powder, Seaweed, Laminaria

B
Evidence

Kelp is a natural source of iodine and trace minerals, supporting thyroid function and providing marine-derived nutrients.

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Daily target & upper limit

150 mcg / day · UL 1100 mcg

Kelp has an established daily reference intake. See best forms, label synonyms, upper-limit warnings, and top-scoring supplements:

Kelp dosage reference →

Primary uses

  • Thyroid support
  • Iodine supplementation
  • Trace minerals
  • Metabolic support

How it works

  • Provides bioavailable iodine
  • Supports thyroid hormone synthesis
  • Trace mineral nutrition

Dosage

Typical range
150-500 mcg iodine equivalent
Timing
With meals
With food
Yes
Duration
Monitor thyroid with long-term use
Special populations
Iodine-deficient populations

Forms

  • Standardized iodine· 95/100
  • Organic kelp· 90/100
  • Whole thallus· 85/100
  • Powder· 80/100

Safety

Common side effects

  • Metallic taste
  • GI upset

Contraindications

  • Hyperthyroidism
  • Hashimotos without guidance

Products containing Kelp

Top-scoring supplements in our catalog that list Kelp on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.

Thorne
Daily Greens Plus
84
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Known interactions

Evidence notes

Well-established iodine source, thyroid support

Grade B: Some human trials support key claims; further confirmation needed.

Related in Mineral

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