Researchers at Boston University School of Medicine (BUSM) have brought attention to the potential health impacts for Korean and Korean-American women and their infants from consuming brown seaweed soup. Seaweed is a known source of dietary iodine, particularly in Korea; however, there is no scientific data on the iodine content in Korean seaweed soup.
Written as a Letter to the Editor for the journal Thyroid and published online, the authors discuss the adverse effects of consuming excess amounts of iodine, which include iodine-induced hypothyroidism, thyrotoxicosis and goiter. Previous studies have shown that iodine content in breast milk of Korean lactating mothers has a strong correlation with the frequency and quantity of brown seaweed soup consumption.
“Traditionally, Korean and Korean-American women eat brown seaweed soup daily during their early postpartum period, yet they are not aware of risks associated with eating too much iodine-rich foods,” said the lead author, Soo Rhee, MD, from the section of Endocrinology, Diabetes and Nutrition at BUSM.
The researchers randomly picked 10 different brands of brown seaweed available in the U.S. for their research. Utilizing the same recipe for each batch, the researchers measured the iodine concentration of the dry seaweed, the seaweed soup broth and the blended mixture of broth and solid soup. What they found were varied amounts of iodine in the soups based on where the seaweed was from and when it was harvested. Given the range of iodine content in the soup recipes, as well as previous research looking at daily brown seaweed soup consumption in postpartum Korean women, many of these women could potentially be ingesting more iodine than the World Health Organization and Institute of Medicine recommends.
The researchers conclude that additional studies need to be done to evaluate the potential adverse effects of long-term high dietary iodine consumption in Korean and Korean-American women and their infants. Additionally, the researchers recommend that health care providers be educated about Korean and Korean-American women dietary habits so that they can provide more guidance as to what their patients should be eating that is healthy for both the women and their infants.
The letter’s co-authors, Lewis Braverman, MD, Sam Pino, Xuemei He, MD, and Elizabeth Pearce, MD, are all from BUSM’s Endocrinology, Diabetes and Nutrition section.
About Boston University School of Medicine
Originally established in 1848 as the New England Female Medical College, and incorporated into Boston University in 1873, Boston University School of Medicine today is a leading academic medical center with an enrollment of more than 700 medical students and more than 800 masters and PhD students. Its 1,246 full and part-time faculty members generated more than $335 million in funding in the 2009-2010 academic year for research in amyloidosis, arthritis, cardiovascular disease, cancer, infectious disease, pulmonary disease and dermatology among others. The School is affiliated with Boston Medical Center, its principal teaching hospital, the Boston and Bedford Veterans Administration Medical Centers and 16 other regional hospitals as well as the Boston HealthNet.
Contact: Jenny Eriksen Leary
Boston University Medical Center