The Basics
What is Seaweed / Fucus vesiculosus Undaria pinnatifida?
A type of brown seaweed. People use Fucus vesiculosus for conditions such as thyroid disorders, iodine deficiency, obesity, and many others, but there is no good scientific evidence to support these uses.
Brand names for Seaweed / Fucus vesiculosus Undaria pinnatifida
N/A
How Seaweed / Fucus vesiculosus Undaria pinnatifida is classified
Complementary Therapies, Food, Phytotherapy, Plants, Medicinal
Seaweed / Fucus vesiculosus Undaria pinnatifida During Pregnancy
Seaweed / Fucus vesiculosus Undaria pinnatifida pregnancy category
Category N/ANote that the FDA has deprecated the use of pregnancy categories, so for some medications, this information isn’t available. We still think it’s useful to list historical info, however, given what a common proxy this has been in the past.
What we know about taking Seaweed / Fucus vesiculosus Undaria pinnatifida while pregnant
N/A
Taking Seaweed / Fucus vesiculosus Undaria pinnatifida While Breastfeeding
What are recommendations for lactation if you're taking Seaweed / Fucus vesiculosus Undaria pinnatifida?
Kelp (Fucus vesiculosus, other Fucus species, and Ascophyllum nodosum), also known as bladderwrack, consists of the dried whole plant. It contains soluble fiber (e.g., alginic acid), vitamin B12, iron and iodine. It can also contain heavy metals (e.g., arsenic, cadmium, lead). Brown seaweed (Undaria pinnatifida) is a purported galactogogue in some Asian cultures; however, no scientifically valid clinical trials support this use. Galactogogues should never replace evaluation and counseling on modifiable factors that affect milk production.[1] No data exist on the excretion of any organic components of seaweed into breastmilk; however, iodine is actively transported into breastmilk and heavy metals are excreted into milk. For further information on iodine in breastmilk and its potential adverse effects, see the iodine record in LactMed. Some sources recommend against using seaweed during breastfeeding because of its high iodine content,[2][3][4] and potential contamination with heavy metals. Dietary supplements do not require extensive pre-marketing approval from the U.S. Food and Drug Administration. Manufacturers are responsible to ensure the safety, but do not need to prove the safety and effectiveness of dietary supplements before they are marketed. Dietary supplements may contain multiple ingredients, and differences are often found between labeled and actual ingredients or their amounts. A manufacturer may contract with an independent organization to verify the quality of a product or its ingredients, but that does not certify the safety or effectiveness of a product. Because of the above issues, clinical testing results on one product may not be applicable to other products.
Maternal / infant drug levels
Kelp (Fucus vesiculosus, other Fucus species, and Ascophyllum nodosum), also known as bladderwrack, consists of the dried whole plant. It contains soluble fiber (e.g., alginic acid), vitamin B12, iron and iodine. It can also contain heavy metals (e.g., arsenic, cadmium, lead). Brown seaweed (Undaria pinnatifida) is a purported galactogogue in some Asian cultures; however, no scientifically valid clinical trials support this use. Galactogogues should never replace evaluation and counseling on modifiable factors that affect milk production.[1] No data exist on the excretion of any organic components of seaweed into breastmilk; however, iodine is actively transported into breastmilk and heavy metals are excreted into milk. For further information on iodine in breastmilk and its potential adverse effects, see the iodine record in LactMed. Some sources recommend against using seaweed during breastfeeding because of its high iodine content,[2][3][4] and potential contamination with heavy metals. Dietary supplements do not require extensive pre-marketing approval from the U.S. Food and Drug Administration. Manufacturers are responsible to ensure the safety, but do not need to prove the safety and effectiveness of dietary supplements before they are marketed. Dietary supplements may contain multiple ingredients, and differences are often found between labeled and actual ingredients or their amounts. A manufacturer may contract with an independent organization to verify the quality of a product or its ingredients, but that does not certify the safety or effectiveness of a product. Because of the above issues, clinical testing results on one product may not be applicable to other products.
Possible effects of Seaweed / Fucus vesiculosus Undaria pinnatifida on milk supply
Relevant published information was not found as of the revision date.
Possible alternatives to Seaweed / Fucus vesiculosus Undaria pinnatifida
None listed
List of References
Lactation sources: Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK501922/1. Brodribb W. ABM Clinical Protocol #9: Use of galactogogues in initiating or augmenting maternal milk production, second revision 2018. Breastfeed Med. 2018;13:307-14. PMID: 29902083
2. Kopec K. Herbal medications and breastfeeding. J Hum Lact. 1999;15:157-61. PMID: 10578793
3. Consolini AE, Ragone MI. Patterns of self-medication with medicinal plants and related adverse events – a South American survey. Curr Drug Saf. 2010;5:333-41. PMID: 20615178
4. Rhee SS, Braverman LE, Pino S et al. High iodine content of Korean seaweed soup: a health risk for lactating women and their infants? Thyroid. 2011;21:927-8. PMID: 21745110
5. Dasgupta PK, Kirk AB, Dyke JV, Ohira S. Intake of iodine and perchlorate and excretion in human milk. Environ Sci Technol. 2008;42:8115-21. PMID: 19031911
6. Moon S, Kim J. Iodine content of human milk and dietary iodine intake of Korean lactating mothers. Int J Food Sci Nutr. 1999;50:165-71. PMID: 10627832
7. Chung HR, Shin CH, Yang SW et al. Subclinical hypothyroidism in Korean preterm infants associated with high levels of iodine in breast milk. J Clin Endocrinol Metab. 2009;94:4444-7. PMID: 19808851
8. Emder PJ, Jack MM. Iodine-induced neonatal hypothyroidism secondary to maternal seaweed consumption: A common practice in some Asian cultures to promote breast milk supply. J Paediatr Child Health. 2011;47:750-2. PMID: 21276114
9. Hulse T. Transient neonatal hypothyroidism resulting from maternal ingestion of a traditional Korean seaweed soup. Horm Res Paediatr. 2012;78 (Suppl 1):127-8. Abstract. DOI: doi:10.1159/000343182
Disclaimer: This material is provided for educational purposes only and is not intended for medical advice, diagnosis, or treatment. Consult your healthcare provider with any questions.
