Liu Xiaobing, Wang Jun, Li Yajie, Tan Hongxing, Yu Wei, Yan Junan, Piao Jianhua, Liu Xiaoli, Yang Xiaoguang
National Institute for Nutrition and Health Chinese Center for Disease Control and Prevention Beijing China.
Shenzhen Polytechnic School of Food and Drug Shenzhen Guangdong China.
Food Sci Nutr. 2025 Sep 4;13(9):e70818. doi: 10.1002/fsn3.70818. eCollection 2025 Sep.
The consumption of kombu plays an important role in the traditional dietary habits of East-Asian countries. However, data on the metabolic profile of kombu-derived iodine remain limited. Totally, 20 Chinese participants (age 19.6 ± 2.7 years) were recruited and allocated to two parallel intervention groups. One consisted of a meal with kombu supplement (providing 993 and 1735 μg iodine), and the other of potassium iodide (KI, containing 547 and 1263 μg iodine) at the two interventions. The iodine bioavailability was assessed based on the 0-24 h urine samples, and the metabolic response was characterized by urinary iodine excretion velocity (UIEV) at 18 time points during the following 48 h. Iodine speciation in kombu was determined by liquid chromatography and inductively coupled plasma mass spectrometry (LC-ICPMS). 18 Chinese participants finally completed this study and two participants dropped out. The 0-24 h urinary iodine concentration (UIC) was consistently lower in the kombu group compared to the KI group (95 μg/L vs. 113 μg/L, > 0.05; 109 μg/L vs. 223 μg/L, < 0.001) at the interventions. The corresponding iodine bioavailability was significantly lower in the kombu supplement than in the KI (29.5% vs. 83.5%, < 0.001; 23.7% vs. 63.7%, < 0.001). The UIEV appeared to have distinct fluctuations, which exhibited a gradual increase for the kombu, reaching peaks of 22 and 25 μg/h, while demonstrating a steep surge for the KI, attaining higher peaks of 57 and 109 μg/h, respectively. The 50.9%-55.0% of total iodine in kombu was in inorganic iodide forms. This study showed a lower iodine bioavailability in participants receiving the kombu supplement compared to the KI. Furthermore, the UIEV demonstrated a moderate metabolic response following kombu intake, suggesting its potential as an alternative to iodized salt.
海带的食用在东亚国家的传统饮食习惯中起着重要作用。然而，关于海带衍生碘的代谢特征的数据仍然有限。总共招募了20名中国参与者（年龄19.6±2.7岁），并将其分配到两个平行干预组。一组食用添加海带的餐食（提供993和1735μg碘），另一组在两次干预时食用碘化钾（KI，含547和1263μg碘）。基于0至24小时的尿液样本评估碘的生物利用度，并通过在接下来48小时内18个时间点的尿碘排泄速度（UIEV）来表征代谢反应。通过液相色谱和电感耦合等离子体质谱法（LC-ICPMS）测定海带中的碘形态。最终18名中国参与者完成了这项研究，两名参与者退出。在干预时，海带组的0至24小时尿碘浓度（UIC）始终低于KI组（95μg/L对113μg/L，>0.05；109μg/L对223μg/L，<0.001）。海带补充剂中相应的碘生物利用度明显低于KI（29.5%对83.5%，<0.001；23.7%对63.7%，<0.001）。UIEV似乎有明显波动，海带组呈现逐渐上升趋势，达到22和25μg/h的峰值，而KI组则出现急剧上升，分别达到57和109μg/h的更高峰值。海带中50.9%-55.0%的总碘以无机碘化物形式存在。这项研究表明，与KI相比，接受海带补充剂的参与者碘生物利用度较低。此外，UIEV表明摄入海带后有适度的代谢反应，表明其作为碘盐替代品的潜力。
