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Hormonal/Digestion/Immunity

Sea moss

Red algae supplement providing iodine and trace minerals, traditionally used for thyroid and digestive support.

Sea moss
30
score
D
evidence
Caution
risk

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Use with caution

This supplement may interact with medications, medical conditions or sensitive populations. Review safety before use.

Quick Take

Lacks robust clinical evidence; mostly traditional use and small pilot studies. Caution due to variable iodine content.

Sea moss is a species of red algae (Chondrus crispus and related species) harvested from Atlantic and Caribbean coasts. It is naturally rich in iodine, sulfated polysaccharides, and trace minerals. Its mucilaginous fibers may provide prebiotic effects in the gut, while its iodine content can influence thyroid hormone synthesis. Limited preliminary research suggests potential immunomodulatory and antioxidant effects from algal polysaccharides, though robust human trials are lacking.

Potential benefits

01
May support thyroid function
02
May support digestive health
03
May support immune function
04
May soothe respiratory mucosa

Protocol

Amount
10-20 g rehydrated gel or 1000-2000 mg dry powder
Frequency
Once daily
When
With meals to improve tolerability.

Onset Time

Days to weeks for digestive effects; thyroid changes depend on iodine status.

Who Should Consider

Adults with low dietary iodine intake
People seeking soluble fiber sources
Those interested in traditional marine remedies
Individuals with low seaweed consumption

How It Works

Sea moss contains high levels of iodine, which is required for thyroid hormone production (T3/T4). Its sulfated polysaccharides (including carrageenan) demonstrate immunomodulatory and antioxidant activity in vitro by modulating cytokine production and scavenging free radicals. The mucilaginous fiber may act as a prebiotic, feeding beneficial gut bacteria and slowing intestinal transit.

Updated 5/19/2026

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