title: Author's Response to the Letter: Does the optimal BMI really vary by age and sex?, by Xu et al.
authors.affiliation: Department of Preventive Medicine and Public Health, Catholic Kwandong University College of Medicine, Gangneung, Republic of Korea, flyhigh@cku.ac.kr.
authors.forename: Sang-Wook
authors.initials: SW
authors.lastname: Yi
authors.affiliation: Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea and.
authors.forename: Heechoul
authors.initials: H
authors.lastname: Ohrr
authors.affiliation: Institute for Occupational and Environmental Health, Catholic Kwandong University, Gangneung, Republic of Korea.
authors.forename: Jee-Jeon
authors.initials: JJ
authors.lastname: Yi
mesh_terms: D015992:Body Mass Index; D006801:Humans