Arame

Arame (Eisenia bicyclis): A Comprehensive Reference

1. Identity and Botanical Classification

Nomenclature and Taxonomy

Arame (荒布; Eisenia bicyclis, syn. Ecklonia bicyclis), also called "sea oak," is a species of kelp within the brown algae, best known for its use in Japanese cuisine. The brown alga belongs to the order Laminariales within the class Phaeophyceae, and is distributed along the temperate coasts from the central to southern parts of Japan, where it forms dense underwater kelp beds called "marine forests" in the sub-tidal zone. Eisenia bicyclis (Kjellman) Setchell (Lessoniaceae) is a perennial and daily consumed edible brown alga that inhabits the middle Pacific coastlines of Korea and Japan.

The name "arame" appears in the Japanese written character 荒布, and the species has historically been traded under closely related names. Studies on wooden shipping tags (mokkan) from the 7th–8th centuries indicate that products labeled as arame (滑海藻/阿良女) are conjectured to have been E. cava or E. bicyclis, depending on the places of origin recorded on the tags. A pioneering Japanese authority on algae, Kichisaburo Endo, noted that the terms kajime and arame are confounded regionally, and some places call the kajime "arame," and vice versa.

Morphology and Habitat

Arame is indigenous to temperate Pacific Ocean waters centered near Japan, although it is deliberately cultured elsewhere, including South Korea. It grows and reproduces seasonally. Two flattened oval fronds rise from a stiff woody stipe which can be up to about 1 metre (3.3 ft) tall. The fronds are shed and new ones are formed annually. The plant appears both branched and feathered. It is a brown alga abundant on the coasts of Japan and Korea, and it lives attached to rocks in shallow water and is collected manually since it is quite strong.

Common Forms and Preparations

Arame may be harvested by divers manually or mechanically, and the dried form is available year-round. It is one of many species of seaweed used in Asian cuisine. Usually purchased in a dried state, it is reconstituted quickly, taking about five minutes. Arame comes in dark brown strands, has a mild, semi-sweet flavor, and a firm texture.

Only the most tender fronds of arame are selected and hand-harvested in the summer. The fronds are washed and sun dried. After drying, the fronds are then steamed for five hours to soften them and enhance their color, then finely shredded to make them easy to use and quick to prepare before naturally air drying.

Arame is added to appetizers, casseroles, muffins, pilafs, soups, toasted dishes, and many other types of food. Arame is also used as a raw material for alginate, a very popular food additive, and holds potential for pharmaceutical applications due to its rich phlorotannin extracts. Beyond whole-food preparations, arame-derived extracts — particularly phlorotannin-rich fractions, alginate, fucoidan, and fucoxanthin isolates — are studied in laboratory settings and used in commercial supplement and cosmeceutical formulations.

2. Traditional and Historical Use

Deep Antiquity: Jomon to Nara Periods

Use of seaweed (brown algae) as food can be traced back to the fourth century in Japan, and to the sixth century in China. Seaweed such as Eisenia bicolor and Sargassum arame has been discovered in ruins dating from the Jomon to Yayoi periods. It is believed that these seaweeds were dried and eaten as is, or added to stews and soups.

The oldest law drafted in Japan in 701 CE, the "Taiho Ritsuryo," stated that arame was to be used as a tax alongside wakame and nori. The Kojiki and Nihon Shoki record that seaweed was presented to the imperial court as a tribute. At the time, it was fresh seaweed, not the dried seaweed known today. It was highly valued as a precious food ingredient.

Sacred and Ritual Use

Prized as a specialty of the Ise region, arame grows wild in deep tidal pools at the ocean's edge. Over a thousand years ago, arame was collected and used as a sacred offering at the famous Ise Shrine. To this day, Ise Wild Arame is harvested in the same way. In Mie Prefecture, arame is used for offerings to Ise Shrine, a headquarters of Shinto.

Culinary and Medicinal Tradition

Arame has been a traditional part of the Japanese diet since ancient times. Arame is one of the seaweed species traditionally used in Japan, alongside nori and konbu. Arame is in the same family as kombu seaweed but, unlike kombu, arame does not produce dashi broth, so it is mainly used for stir-frying.

Historically, arame has been valued in East Asian cultures not only as a food but also for its medicinal properties. Traditional Japanese and Korean remedies have long utilized arame for its rich mineral content, particularly iodine, calcium, magnesium, and iron. Its use in folk medicine often centered on supporting thyroid health, boosting vitality, and aiding in the treatment of goiter due to its natural iodine content.

Seaweeds have a long history and were appreciated as offerings in Shinto rituals in the era of the Yamato Dynasty. Under the "Taiho Ritsuryo Code," seaweed was subject to taxation.

3. Key Constituents and Active Compounds

Overview of Bioactive Compound Classes

Arame (Eisenia bicyclis), a marine brown alga, is known to be a rich source of natural bioactive compounds such as fucoxanthin, phlorotannins, chlorophylls, carotenoids, and tocopherol. The main bioactive compounds reported for arame are phenolic compounds and polysaccharides. The most abundant phenolic compounds are phlorotannins (eckol and other phloroglucinol derivatives), which have been reported to have various biological activities, notably anti-diabetic and antioxidant activities.

Phlorotannins

Prominent among arame's bioactive compounds are phlorotannins, a class of polyphenolic metabolites unique to brown algae. Key phlorotannins identified in arame include eckol, dieckol, phlorofucofuroeckol A, fucofuroeckol A, and 8,8'-bieckol. Arame also contains the phlorotannins phlorofucofuroeckol A, dioxinodehydroeckol, fucofuroeckol A, eckol, dieckol, triphloroethol A, and 7-phloroethol. From ethyl acetate fractions, six known phlorotannins have been isolated: phloroglucinol, eckol, dieckol, 7-phloroeckol, phlorofucofuroeckol A, and dioxinodehydroeckol, alongside the sterol fucosterol.

Arame contains phlorotannins, carotenoids, fucoxanthin, and tocopherol. Its effects on allergies, diabetes, inflammation, and cancer have all been studied. While E. bicyclis is rich in phlorotannins, it also contains other bioactive compounds such as carotenoids, fucoxanthin, quercetin, and caffeic acid.

Polysaccharides

The major polysaccharide of E. bicyclis is sodium alginate, comprising 15.8% of the dry defatted alga weight. The yields of laminaran and fucoidan were 1.4% and 1.3% of the dry defatted alga weight, respectively. The alga contains laminaran (1,3;1,6-β-D-glucan) with a unique structure, a high content of 1,6-linked D-glucose residues (the ratio of 1,3:1,6 linkage is 1.5:1), and an unusually high molecular weight (19–27 kDa). The fucoidan fractions isolated from E. bicyclis are sulfated and acetylated heteropolysaccharides that differ in their sulfate content and monosaccharide composition.

Arame, belonging to the Laminariales order, contains a wide variety of organic compounds, including bromophenols, polysaccharides such as laminarin, polymeric phloroglucinols, and other phlorotannins such as dieckol and eckol.

Carotenoids

Fucoxanthin is a well-known marine carotenoid of the xanthophyll family with bioactive compounds. It is profusely found in brown seaweeds, providing more than 10% of the total creation of natural carotenoids. Fucoxanthin is found in edible brown seaweed macroalgae such as Undaria pinnatifida, Laminaria japonica, and Eisenia bicyclis. Crude phlorotannins of E. bicyclis analyzed by FT-IR, LC-MS, UHPLC, and UV chromatography also showed the occurrence of the carotenoid zeaxanthin (0.5 mg/kg).

Arame is among the brown algae studied as a raw material for fucoxanthin. Research shows that each gram of macroalgae contains 0.1–1.0 mg fucoxanthin. Fucoxanthin is hydrolyzed into fucoxanthinol by digestive enzymes such as lipase in the gastrointestinal tract and taken up by intestinal cells; fucoxanthinol is viewed as the essential active metabolite in humans.

Minerals and Other Nutrients

Arame is high in calcium, iodine, iron, magnesium, and vitamin A, as well as being a dietary source of many other minerals. Arame is rich in essential minerals such as iodine, calcium, magnesium, and potassium, as well as dietary fiber, vitamins (notably vitamin K and folate), and unique polysaccharides such as fucoidan and alginate. As for minerals, arame has high contents of iron, magnesium, and calcium, but iodine is the most relevant, with contents reaching 30 mg per 100 g of product (approximately 5000% of the recommended daily value).

Unique Peptides and Other Compounds

Arame contains the storage polysaccharide laminarin and the tripeptide eisenin, a peptide with immunological activity. Lignan content in arame is also noted by several sources. It is rich in chelated calcium, which enhances its absorption in the body.

4. Mechanisms of Action

Phlorotannin-Mediated Antioxidant Activity

With the exception of eckol, the oxygen radical absorbance capacity (ORAC) values of tested phlorotannins from Eisenia bicyclis were higher than those of well-known antioxidants (epigallocatechin gallate, resveratrol, and L-ascorbic acid) used as positive controls. Dieckol and fucofuroeckol A were found to have stronger antioxidant activity than representative polyphenols such as kaempferol, quercetin, myricetin, and chlorogenic acid derived from terrestrial plants. Like many other phenolic compounds, phlorotannins have antioxidant activity and can protect algal cells against UV radiation and oxidative stress.

Anti-Inflammatory Mechanisms

Although individual phlorotannins from edible brown algae have been reported to possess strong anti-inflammatory activity, the responsible components of Eisenia bicyclis have been studied via inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) and tert-butylhydroperoxide (t-BHP)-induced reactive oxygen species (ROS), along with suppression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in RAW 264.7 macrophage cells.

LPS, an inflammatory mediator, enhanced the production of cytokines including IL-1, IL-6, IL-8, IL-10, TNF-α, chemokine CXCL10, and NF-κB in differentiated THP1 macrophage cells. On differentiated human monocytic cell line LPS-induced THP1 cells, crude phlorotannins from E. bicyclis (CPEb) were found to have anti-inflammatory effects by reducing the expression of IL-1, IL-6, IL-8 (1.2-fold), CXCL10, NF-κB, and TNF-α.

An extract from Eisenia bicyclis, previously shown to possess anti-inflammatory activity, was found to stabilize lysosomal membranes in vitro as determined by measurement of inhibition of the marker enzyme β-glucuronidase. Some anti-inflammatory activity was also attributed to counterirritancy.

Antidiabetic Mechanisms

Crude phlorotannins from E. bicyclis (CPEb) promoted glucose absorption in differentiated C2C12 myotubes under both basal and insulin-stimulated conditions. CPEb increased IRS/AKT-dependent glucose absorption and also activated the AMPK pathway. Anti-α-glucosidase, anti-inflammatory, and antioxidant activity of CPEb indicate their role in treating hyperglycemia by scavenging ROS and inflammatory responses.

Fucoxanthin shows antiobesity effects in animal models of type 2 diabetes through the uncoupling protein (UCP) 1 expression in white adipose tissue (WAT) of KKAy mice.

Antithrombotic Mechanisms

E. bicyclis inhibits agonist-induced platelet activation and thrombus formation through modulation of the P2Y12 receptor downstream signaling pathway, suggesting its therapeutic potential as an anti-platelet and antithrombotic agent. Research examined the pharmacological effects of E. bicyclis on the modulation of platelet function and its underlying mechanism in the treatment and prevention of cardiovascular disease.

Gut Microbiota and mTOR Pathway Modulation

Studies have explored the effects of E. bicyclis ethanol extract on anti-inflammatory activity, intestinal barrier protection, and gut microbial dynamics. The alga was hypothesized to protect the integrity of the intestinal barrier and reduce inflammation by inhibiting mTOR axis-related genes, inhibiting the phosphorylation of NF-κB, and regulating the intestinal flora.

5. Scientific Evidence by Area of Use

5.1 Antioxidant Activity

Phlorotannins and carotenoids from arame possess a wide range of pharmacological activities including antioxidant, anti-inflammatory, anticancer, neuroprotective, antiviral, and antidiabetic properties.

Evidence type and strength: Studies on antioxidant activity from arame are primarily in vitro. ORAC (hydrogen atom transfer-based oxygen radical absorbance capacity) assays comparing isolated phlorotannins from Eisenia bicyclis found that dieckol and fucofuroeckol A exhibited stronger antioxidant activity than representative terrestrial polyphenols including kaempferol, quercetin, myricetin, and chlorogenic acid. No controlled human clinical trials specifically measuring antioxidant endpoints from arame consumption have been identified in the peer-reviewed literature. Evidence at this stage is in vitro only and cannot yet be extrapolated to clinical outcomes.

5.2 Anti-Inflammatory Activity

The majority of investigations on phlorotannins derived from brown algae have demonstrated their potential as antioxidant, anti-inflammatory, antidiabetic, antitumor, antihypertensive, anti-allergic, hyaluronidase enzyme inhibitors and matrix metalloproteinase (MMP) inhibitors.

A study investigated the combined effects of phlorotannins (TAs) isolated from Eisenia bicyclis and Lactobacillus casei (LC) on inflammatory markers in ulcerative colitis, with a focus on the aryl hydrocarbon receptor (AhR) axis. In vitro experiments revealed anti-inflammatory effects of the phlorotannin fraction isolated from E. bicyclis, especially in synergy with LC. In vivo experiments showed that a synbiotic combination of TAs and LC mitigated DSS-induced colitis and reduced intestinal shortening and splenic hypertrophy.

Evidence type and strength: Anti-inflammatory research on arame is primarily in vitro (cell culture, including RAW264.7 macrophages and THP1 cells) and in vivo (rodent models of colitis). A study by Jung et al. revealed that the ethyl acetate, dichloromethane, and methanol fractions of Eisenia bicyclis inhibited NO production in RAW264.7 cells by 45.3%, 41.2%, and 38.2%, respectively. No human clinical trials assessing anti-inflammatory endpoints specifically from arame-derived preparations have been identified in the current literature. Evidence remains preclinical.

5.3 Antidiabetic and Metabolic Effects

Crude phlorotannins from Eisenia bicyclis (CPEb), a common perennial brown seaweed, were screened for pharmacological activities such as anti-inflammatory, antioxidant, and antidiabetic effects. The pharmacological effects of the crude phlorotannins isolated from Eisenia bicyclis were analyzed. Phlorotannins studied by FTIR, LC-MS, UHPLC, and UV chromatography showed the occurrence of dieckol, 8,8'-bieckol, and fucofuroeckol.

Fucoxanthin, identified as a constituent of E. bicyclis, has shown antidiabetic promise in preclinical models. Fucoxanthin has demonstrated anti-inflammatory, anti-diabetic, antiobesity, and anticancer effects. Fucoxanthin shows antiobesity effects in animal models of type 2 diabetes through uncoupling protein (UCP) 1 expression in white adipose tissue (WAT) of KKAy mice.

Evidence type and strength: Antidiabetic evidence for arame-derived constituents comes from in vitro enzyme-inhibition assays (α-glucosidase, α-amylase inhibition) and animal studies, along with cell-line (C2C12 myotube) experiments demonstrating glucose uptake enhancement. No controlled human clinical trials testing arame specifically for glycemic outcomes have been identified. Evidence is preliminary and preclinical.

5.4 Cardiovascular and Antithrombotic Effects

Eisenia bicyclis has been studied for anti-allergic and anti-cancer effects; however, its effects on the cardiovascular system, especially on platelet function, were further explored. An E. bicyclis extract (EBE) was prepared and in vitro effects on ADP-induced platelet aggregation, granule secretion, intracellular calcium ion ([Ca²⁺]i) mobilization, fibrinogen binding to integrin αIIbβ3, and clot retraction were evaluated.

Arame (Eisenia bicyclis) inhibits the formation of blood clots and shows therapeutic potential for use as an antiplatelet and antithrombotic agent to prevent thrombotic events.

Evidence type and strength: Antithrombotic and cardiovascular evidence consists of in vitro platelet aggregation assays and animal thrombosis models. No published human clinical trials evaluating arame for cardiovascular or antithrombotic endpoints have been identified. Evidence is preclinical and mechanistic only.

5.5 Anticancer Activity

Phloroglucinol and its essential polymers — eckol, dieckol, phlorofucofuroeckol A, and 8,8'-bieckol — isolated from the brown alga Eisenia bicyclis show significant anticancer activity.

Fucoxanthin, found in edible brown seaweed macroalgae including Eisenia bicyclis, possesses pharmacological properties that include antioxidant, anti-tumor, anti-inflammatory, antiobesity, anticancer, and antihypertensive effects. Fucoxanthin has been reported to penetrate the blood–brain barrier. It is exceptional among other carotenoids for its anti-neurodegenerative effects against oxidative stress, amyloid protein aggregation, neurotransmission dysregulation, and gut microbial disorder.

Evidence type and strength: Anticancer evidence for arame-derived compounds is exclusively from in vitro cell-line studies and some animal models. There are no human clinical trials or controlled observational studies specifically evaluating arame for cancer prevention or treatment outcomes. This area of research is preliminary and mechanistic. Results should not be interpreted as demonstrating clinical efficacy.

5.6 Gut Health and Colitis

Ulcerative colitis (UC) is a chronic inflammatory disease of the colon that is associated with dysbiosis in the gut microbiota. Eisenia bicyclis, a marine alga, is known for its anti-inflammatory, antioxidant, and gut microbiota-modulating properties. A 2025 study published in Foods explored the mechanisms by which a 70% ethanol extract of E. bicyclis may alleviate UC through both in vitro and in vivo experiments.

LC-MS/MS analysis revealed eckol, 7-phloroeckol, dieckol, phlorofucofuroeckol A, and fucofuroeckol as key phenolic compounds present in the extract. The administration of E. bicyclis significantly improved symptoms in a dextran sulfate sodium (DSS)-induced colitis mouse model by reducing intestinal shortening, splenomegaly, and histological scores. Both cell and animal studies demonstrated that E. bicyclis suppressed the release of inflammatory cytokines, downregulated the mRNA expression of genes related to the mTOR pathway, and reduced the p-mTOR/mTOR ratio.

A separate study used in vitro and in vivo colitis models to demonstrate that the combined administration of E. bicyclis phlorotannins (TA) and Lactobacillus casei (LC) exerted anti-inflammatory effects by modulating the AhR axis and influencing gut microbiota composition. The synergistic effect of TA and LC fermentation metabolite uptake was hypothesized to demonstrate that AhR regulates the gut microbiota through the basal axis, providing potent anti-inflammatory and protective effects on intestinal tight junctions.

Evidence type and strength: Gut health evidence is from in vitro cell studies and murine (mouse) colitis models published in 2024–2025. These are preclinical findings. No human clinical trials evaluating arame for inflammatory bowel disease or gut microbiota outcomes have been published.

5.7 Thyroid Function

Arame algae and seaweed in general are a source of the essential trace element iodine. Iodine plays an important role in thyroid function, as it is required for the synthesis of thyroid hormones. Arame's iodine content can reach 30 mg per 100 g of product.

Evidence type and strength: While iodine's role in thyroid hormone synthesis is well established, the effects of arame specifically on thyroid health have not been studied in human clinical trials. The very high iodine content of arame is equally relevant as a safety consideration (see Section 7). Although iodine is necessary in the diet, either an excess or a deficiency in iodine may cause disorders related to thyroid function. The consequences of these pathologies can be very serious in children and pregnant women.

5.8 Skin and Photoprotective Effects

A 2021 study demonstrated the photoprotective effect of an extract of Eisenia bicyclis, which can prevent UVB-induced skin damage. Dioxinodehydroeckol from Ecklonia cava and fucofuroeckol-A derived from the brown seaweed Ecklonia stolonifera can protect against UVB radiation, effects also relevant to closely related phlorotannin-containing genera.

Evidence type and strength: Skin photoprotective evidence for arame phlorotannins is from in vitro cell-culture and laboratory assay studies. No human clinical trials have been conducted to evaluate topical or oral arame preparations for skin photoprotection outcomes.

6. Body Systems and Health Areas

• Endocrine/Thyroid system: Arame is a source of the essential trace element iodine, which plays an important role in thyroid function as it is required for the synthesis of thyroid hormones.
• Cardiovascular system: E. bicyclis inhibits agonist-induced platelet activation and thrombus formation through modulation of the P2Y12 receptor downstream signaling pathway, suggesting therapeutic potential as an antiplatelet and antithrombotic agent.
• Metabolic/Glycemic system: CPEb increased IRS/AKT-dependent glucose absorption and activated the AMPK pathway; anti-α-glucosidase activity indicates a role in potentially treating hyperglycemia.
• Gastrointestinal system: Arame is known for anti-inflammatory, antioxidant, and gut microbiota-modulating properties. Its polysaccharide content (alginate, fucoidan, laminarin) contributes to its dietary fiber profile.
• Immune system: Arame contains the tripeptide eisenin, a peptide with immunological activity.
• Integumentary (skin) system: An extract of Eisenia bicyclis has demonstrated photoprotective effects and can prevent UVB-induced skin damage.
• Musculoskeletal system: Arame is rich in chelated calcium, which enhances its absorption in the body. Calcium and magnesium from arame contribute to bone and muscle function.

7. Dosage Forms and Reported Dosages

Arame is consumed as a whole food (dried, rehydrated strands) and is also extracted into various forms for research and supplemental use. The following dosages are reported only as cited in published sources and do not constitute recommendations.

• Whole food / culinary use: Usually purchased in a dried state, it is reconstituted quickly, taking about five minutes. No standardized dietary serving size has been established by regulatory bodies for arame as a supplement.
• Phlorotannin extract (CPEb), anti-inflammatory and antidiabetic assays: Research evaluated the pharmacological effects of crude phlorotannins isolated from Eisenia bicyclis (CPEb), described as a common perennial brown seaweed, for anti-inflammatory, antioxidant, and antidiabetic effects. In in vitro studies by Raja et al. (2023), phlorotannin extract concentrations were tested in cell culture; specific human dosing has not been established.
• Anti-inflammatory in vitro assay: Anti-inflammatory property was determined through albumin denaturation inhibition and antiprotease activities as up to 39.5% and 41.2%, respectively, at 30 mg/mL concentration. Antidiabetic activity was determined through α-amylase and α-glucosidase inhibition as up to 62.15% and 67.35%, respectively, at 30 mg/mL dosage — values derived from in vitro cell studies, not human doses.
• Colitis model (in vivo, animal): A 70% ethanol extract of E. bicyclis was used in in vitro and in vivo experiments in a murine DSS-colitis model; human equivalents have not been established.
• Protein content estimate: 50 grams of arame contains approximately five grams of protein.

No pharmacopeial monograph (USP, European Pharmacopoeia, WHO monograph, or ESCOP monograph) specifying a standardized human dosage for arame as a dietary supplement has been identified in publicly accessible sources at the time of writing.

8. Safety Considerations and Interactions

Iodine Excess

The myriad variations in iodine concentration between seaweed species, season, and harvest location present challenges to the food industry, since there is limited and conflicting information about how individual seaweeds may impact iodine status and thyroid health. Arame's iodine content can reach 30 mg per 100 g of product (approximately 5,000% of the recommended daily value).

Excess iodine may cause clinical hypothyroidism in many vulnerable individuals, such as after treatment of Graves' disease with radioiodine, after partial thyroidectomy, or in the presence of autoimmune thyroiditis. In subjects with dysfunctional TSH regulation of thyroid production (autonomous nodules), even normal dietary iodine levels may cause iodine-induced hyperthyroidism.

Heavy Metal Contamination

One concern about seaweed consumption is exposure to heavy metals such as arsenic, aluminum, cadmium, lead, rubidium, silicon, strontium, and tin. The contamination of seaweeds with heavy metals depends on habitat or ecology, which has led to inconsistency in research findings.

Seaweeds can entrap heavy metals including Al, Cd, Fe, and particularly arsenic (As). While inorganic As compounds are known to be carcinogenic, the majority of As in seaweeds is present as arsenosugars, which are much less toxic. The concentrations of heavy metals in edible seaweed are generally below toxic levels; however, levels of arsenic (As), cadmium (Cd), and copper (Cu) may exceed toxic levels.

Regulatory Considerations

There are considerable safety concerns related to potential adverse events associated with seaweed consumption, particularly in light of the variable and potentially dangerously high concentrations of iodine and heavy metals (including arsenic species) in certain seaweeds. There is currently limited legislation to require food or supplement companies to disclose mineral, heavy metal, or iodine content of seaweed products or to provide guidance on a safe portion size of certain whole seaweeds in order to prevent excess intakes.

The European Food Safety Authority (EFSA) assessed the relevance of seaweed and halophyte consumption to the dietary exposure to heavy metals (arsenic, cadmium, lead, and mercury) and the iodine intake in the European population. Regulation (EU) 2017/2470 established and updated the "Novel Food Catalogue" that contains all European Union-authorized novel foods. This list included 22 different types of edible seaweed by the end of 2020, but does not specify maximum limits of heavy metals, iodine, and arsenic.

Dried or roasted seaweed provides a source of iodine and protein. However, some seaweed snacks have been found to contain so much iodine that they could be dangerous to consume on a regular basis, and most tested samples were contaminated with concerning levels of toxic heavy metals such as lead and cadmium.

Antiplatelet and Anticoagulant Interactions

E. bicyclis inhibits agonist-induced platelet activation and thrombus formation through modulation of the P2Y12 receptor downstream signaling pathway. The antiplatelet mechanism demonstrated in preclinical studies suggests that arame extracts may theoretically potentiate the effects of anticoagulant or antiplatelet medications, though this interaction has not been studied in humans. No human pharmacokinetic or drug-interaction studies for arame have been identified in the literature.

Thyroid Medication Interactions

Given the documented high iodine content of arame, consumption of large amounts of the whole seaweed or concentrated extracts may be relevant for individuals taking thyroid medications, including levothyroxine or antithyroid drugs. Either an excess or a deficiency in iodine may cause disorders related to thyroid functions, and the consequences of these pathologies can be very serious in children and pregnant women. No specific human studies have evaluated arame-drug or arame-thyroid medication interactions.

Population-Specific Considerations

From seaweed consumption, exposure estimates for cadmium in adult "consumers only" are within the range of previous exposure estimates considering the whole diet, while for inorganic arsenic and lead the exposure estimates represent between 10% and 30% of previous exposures from the whole diet for the adult population. Seaweeds were also identified as important sources of total arsenic, which mainly refers, with some exceptions, to organic arsenic.

References

• Wikipedia — Arame (Eisenia bicyclis)
• Encyclopedia of Life — Eisenia bicyclis Articles
• ScienceDirect Topics — Arame Overview
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• Jung HA et al. — Anti-inflammatory activity of edible brown alga Eisenia bicyclis and its constituents fucosterol and phlorotannins in LPS-stimulated RAW264.7 macrophages. Food Chem Toxicol. 2013 (PubMed)
• Raja R et al. — Efficacy of Eisenia bicyclis phlorotannins in the treatment of diabetes and reducing inflammation. Industrial Crops and Products, 2023 (ScienceDirect)
• Lee et al. — Fucofuroeckol-A from Eisenia bicyclis Inhibits Inflammation in Lipopolysaccharide-Induced Mouse Macrophages via Downregulation of the MAPK/NF-κB Signaling Pathway. Journal of Chemistry, 2016 (Wiley)
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