Antihyperglycemic effect of oolong tea in type 2 diabetes.
OBJECTIVE
To determine the efficacy of oolong tea for lowering plasma glucose in type 2 diabetic patients in Miaoli, Taiwan.


METHODS
A total of 20 free-living subjects who had type 2 diabetes and took hyperglycemic drugs as prescribed were enrolled in the present study. Subjects consumed oolong tea (1,500 ml) or water for 30 days each in a randomized crossover design. Tea was not consumed for 14 days prior to treatments.


RESULTS
Relative to initial concentrations, oolong tea markedly lowered concentrations of plasma glucose (from 229 +/- 53.9 to 162.2 +/- 29.7 mg/dl, P < 0.001) and fructosamine (from 409.9 +/- 96.1 to 323.3 +/- 56.4 micromol/l, P < 0.01), whereas the water control group had not changed (208.7 +/- 61.0 vs. 232.3 +/- 63.1 mg/dl for glucose and from 368.4 +/- 85.0 to 340.0 +/- 76.1 micromol/l for fructosamine).


CONCLUSIONS
Oolong tea may be an effective adjunct to oral hypoglycemic agents in the treatment of type 2 diabetes.
Hosoda
Kazuaki
K
Research Center, Suntory, Osaka, Japan.
Wang
Ming-Fu
MF
Liao
Mei-Ling
ML
Chuang
Chin-Kuang
CK
Iha
Miyuki
M
Clevidence
Beverly
B
Yamamoto
Shigeru
S
D017668:Age of Onset; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy*; D019587:Dietary Supplements; D019270:Fructosamine / Q000097:blood; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D008875:Middle Aged; D013662:Tea; D016896:Treatment Outcome
D015415:Biomarkers; D001786:Blood Glucose; D007004:Hypoglycemic Agents; D013662:Tea; D019270:Fructosamine