title: Effect of jeju water on blood glucose levels in diabetic patients: a randomized controlled trial.
abstract: Jeju water is the groundwater of Jeju Island, a volcanic island located in Republic of Korea. We investigated whether Jeju water improved glycemic control in patients with diabetes. This was a 12-week single-center, double-blind, randomized, and controlled trial. The subjects daily drank a liter of one of three kinds of water: two Jeju waters (S1 and S2) and Seoul tap water (SS). The primary outcome was the proportion of patients in the per-protocol (PP) population achieving glycated hemoglobin (HbA1c) < 7.0% at week 12. In total, 196 patients were randomized and analyzed in the intention-to-treat (ITT) population (66 consuming S1, 63 consuming S2, and 67 consuming SS); 146 patients were considered in the PP population. There were no significant differences in the primary outcomes of the groups consuming S1, S2, or SS. However, the percentage of patients achieving HbA1c < 8% was significantly higher in the S2 group than in the SS group. In the ITT population, the 12-week HbA1c and fructosamine levels were lower in the S1 group than in the SS group and the 4-, 8-, and 12-week fructosamine levels were lower in the S2 group than in the SS group. Although we failed to achieve the primary outcome, it is possible that the Jeju waters improve glycemic control compared with the Seoul tap water in diabetic patients.
authors.affiliation: Department of Internal Medicine, Jeju National University School of Medicine, 102 Jejudaehakno, Jeju City, Jeju 690-756, Republic of Korea.
authors.forename: Gwanpyo
authors.initials: G
authors.lastname: Koh
authors.affiliation: Department of Internal Medicine, College of Medicine, Wonkwang University, 460 Iksan-daero, Iksan-si, Jeollabuk-do 570-740, Republic of Korea.
authors.forename: Dae Ho
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Jeju National University School of Medicine, 102 Jejudaehakno, Jeju City, Jeju 690-756, Republic of Korea.
authors.forename: Sang Ah
authors.initials: SA
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Jeju National University School of Medicine, 102 Jejudaehakno, Jeju City, Jeju 690-756, Republic of Korea.
authors.forename: Eun-Kyung
authors.initials: EK
authors.lastname: Kang
authors.affiliation: Department of Internal Medicine, Jeju National University School of Medicine, 102 Jejudaehakno, Jeju City, Jeju 690-756, Republic of Korea.
authors.forename: Okkyeong
authors.initials: O
authors.lastname: Hwang
authors.affiliation: Department of Internal Medicine, Jeju National University School of Medicine, 102 Jejudaehakno, Jeju City, Jeju 690-756, Republic of Korea.
authors.forename: Hyun-Jung
authors.initials: HJ
authors.lastname: Han
authors.affiliation: Department of Internal Medicine, Jeju National University School of Medicine, 102 Jejudaehakno, Jeju City, Jeju 690-756, Republic of Korea.
authors.forename: Sok Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Jeju National University School of Medicine, 102 Jejudaehakno, Jeju City, Jeju 690-756, Republic of Korea.
authors.forename: Eun-Jin
authors.initials: EJ
authors.lastname: Yang
authors.affiliation: Jeju R&D center, BMI Korea, 2230-4 Yeongpyeong-dong, Jeju-si, Jeju-do 690-140, Republic of Korea.
authors.forename: Min-Kyoung
authors.initials: MK
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Hankook General Hospital, 193 Seogwang-ro, Jeju City, Jeju 690-715, Republic of Korea.
authors.forename: Hyoun-Jung
authors.initials: HJ
authors.lastname: Chin