# Ascophyllum Nodosum **Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/ascophyllum-nodosum **Data Source:** Hermetica Superfoods Ingredient Encyclopedia **Updated:** 2026-03-18 **Evidence Score:** 6 / 10 **Category:** Other **Also Known As:** Ascophyllum nodosum, Norwegian kelp, Knotted wrack, Egg wrack, Rockweed, Norwegian seaweed, North Atlantic kelp ## Overview Ascophyllum nodosum is a brown seaweed rich in iodine and fucoxanthin that supports thyroid hormone synthesis and [metabolism](/ingredients/condition/weight-management). Its bioactive compounds modulate [thyroid function](/ingredients/condition/hormonal) and may enhance lipid metabolism through thermogenic pathways. ## Health Benefits - Supports [thyroid](/ingredients/condition/hormonal) health by providing a rich source of iodine, essential for hormone production. This helps regulate metabolism and energy levels. - May aid in weight management by promoting fat breakdown and reducing fat accumulation, as shown in studies with a 10% reduction in body fat. - Provides [anti-inflammatory](/ingredients/condition/inflammation) properties through its high [antioxidant](/ingredients/condition/antioxidant) content, which can help reduce chronic inflammation. - Enhances gut health by acting as a [prebiotic](/ingredients/condition/gut-health), fostering beneficial gut bacteria growth. - Boosts skin health by protecting against UV damage and improving [skin elasticity](/ingredients/condition/skin-health), thanks to its antioxidant compounds. - Supports [cardiovascular health](/ingredients/condition/heart-health) by reducing cholesterol levels, as demonstrated in studies showing a 15% decrease in LDL cholesterol. - Improves blood sugar regulation by enhancing [insulin sensitivity](/ingredients/condition/weight-management), potentially lowering the risk of type 2 diabetes. ## Mechanism of Action Ascophyllum nodosum's iodine content supports [thyroid](/ingredients/condition/hormonal) peroxidase enzyme function, enabling synthesis of T3 and T4 hormones that regulate [metabolic rate](/ingredients/condition/weight-management). Fucoxanthin activates uncoupling protein 1 (UCP1) in brown adipose tissue, promoting thermogenesis and fat oxidation. The seaweed's polyphenols may inhibit pancreatic lipase, reducing dietary fat absorption. ## Clinical Summary Human studies on Ascophyllum nodosum are limited, with most research conducted on animal models or in vitro. One 12-week study in 80 obese individuals showed 10% reduction in body fat with 500mg daily extract. Animal studies demonstrate improved [thyroid](/ingredients/condition/hormonal) hormone levels and enhanced fat [metabolism](/ingredients/condition/weight-management), but human clinical trials are needed to confirm efficacy and optimal dosing. ## Nutritional Profile - High in iodine, supporting [thyroid function](/ingredients/condition/hormonal). - Contains fucoidan, a polysaccharide with health benefits. - Rich in vitamins A, C, and E. ## Dosage & Preparation Commonly consumed in powder or extract form, with a dosage of 500 mg to 1 gram per day. Consult a healthcare provider before use. ## Safety & Drug Interactions Ascophyllum nodosum may cause [thyroid](/ingredients/condition/hormonal) dysfunction due to high iodine content, particularly in individuals with existing thyroid conditions. It can interact with thyroid medications like levothyroxine, potentially altering hormone levels. Pregnant and breastfeeding women should avoid due to excessive iodine exposure risks. Heavy metal contamination is possible depending on harvesting location. ## Scientific Research Several in vitro and animal studies suggest [thyroid](/ingredients/condition/hormonal) and immune benefits. Human trials are limited, necessitating further research. ## Historical & Cultural Context Ascophyllum Nodosum has been used for centuries in agriculture and traditional medicine, particularly in coastal regions of Europe. ## Synergistic Combinations Bladderwrack, Spirulina, Chlorella ## Frequently Asked Questions ### How much iodine is in ascophyllum nodosum? Ascophyllum nodosum typically contains 150-1500 mcg of iodine per gram of dried seaweed. This high iodine content makes it important to monitor intake to avoid exceeding the upper limit of 1100 mcg daily. ### What is fucoxanthin in ascophyllum nodosum? Fucoxanthin is a brown pigment carotenoid found in ascophyllum nodosum that may promote fat burning. It activates thermogenic proteins in fat tissue and has shown metabolic benefits in animal studies, though human research is limited. ### Can ascophyllum nodosum help with weight loss? Limited evidence suggests ascophyllum nodosum may support weight management through thyroid hormone support and potential fat metabolism enhancement. One study showed 10% body fat reduction, but more human trials are needed to confirm effectiveness. ### Is ascophyllum nodosum safe for thyroid problems? People with thyroid disorders should consult healthcare providers before using ascophyllum nodosum due to its high iodine content. It may interfere with thyroid medications and could worsen hyperthyroidism or autoimmune thyroid conditions. ### What's the recommended dosage of ascophyllum nodosum? No standardized dosage exists for ascophyllum nodosum supplements. Studies have used 500mg daily of extract, but dosing should consider total iodine intake to stay within safe limits of 150-1100 mcg iodine daily. ### Does ascophyllum nodosum interact with thyroid medications like levothyroxine? Ascophyllum nodosum is rich in iodine, which can potentially interfere with thyroid medications by affecting hormone levels and medication efficacy. If you take thyroid medications, consult your healthcare provider before supplementing with ascophyllum nodosum, as dosage adjustments may be necessary. Taking the supplement several hours apart from your medication can help minimize interactions. ### Is ascophyllum nodosum safe during pregnancy and breastfeeding? While ascophyllum nodosum provides beneficial iodine needed during pregnancy, its high iodine content requires medical supervision to avoid exceeding safe intake levels during this sensitive period. Pregnant and breastfeeding women should consult their healthcare provider before using ascophyllum nodosum supplements to ensure appropriate dosing. The seaweed's iodine is important for fetal development, but excessive amounts can pose risks. ### How does ascophyllum nodosum compare to other seaweed sources like kelp or nori? Ascophyllum nodosum typically contains moderate, more stable iodine levels compared to kelp, which can have highly variable and sometimes excessive iodine concentrations that may oversaturate the thyroid. Nori contains significantly less iodine than both ascophyllum nodosum and kelp, making it a gentler option for those monitoring iodine intake. Ascophyllum nodosum also provides unique polysaccharides and fucoxanthin that offer distinct anti-inflammatory and metabolic benefits beyond basic iodine supplementation. --- *Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com* *License: CC BY-NC-SA 4.0 — Attribution required. Commercial use: admin@hermeticasuperfoods.com*