Oolong tea increases plasma adiponectin levels and low-density lipoprotein particle size in patients with coronary artery disease.
BACKGROUND
Oolong tea has been studied for its effect on cardiovascular disease and obesity. Plasma adiponectin levels are reduced in obesity, in patients with type 2 diabetes mellitus and in coronary artery disease (CAD).


OBJECTIVE
To investigate prospectively, whether intake of Oolong tea influences plasma adiponectin levels, low-density lipoprotein (LDL) particle size, total cholesterol, high-density lipoprotein (HDL) cholesterol, LDL cholesterol, serum triglyceride and plasma glucose levels in patients with CAD.


METHODS
Twenty two patients in our study consumed Oolong tea (1000 ml) or water for 1 month in our randomized cross-over study design.


RESULTS
There was a significant difference in plasma adiponectin levels before and after 1 month intake of Oolong tea (6.26 +/- 3.26 microg/ml versus 6.88 +/- 3.28 microg/ml, P < 0.05), and in plasma level LDL particle size (25.02+/-0.67 nm versus 25.31+/-0.60 nm, P < 0.01). The water-consuming control group showed no changes (6.28+/-3.28 microg/ml versus 6.23+/-3.21 microg/ml) in adiponectin levels or LDL particle sizes (25.03+/-0.70 nm versus 25.02+/-0.72 nm). We also observed a significant difference in hemoglobin A1c levels (7.23 +/- 4.45% versus 6.99 +/- 4.30%, P < 0.05) before and after intake of Oolong tea.


CONCLUSIONS
Oolong tea may have beneficial effects on the progression of atherosclerosis in patients with CAD.
Department of Internal Medicine and Cardiology, Graduate School of Medicine, Osaka City University Medical School, 1-4-3 Asahimachi, Abeno-ku, Osaka 545-8585, Japan. shimadak@msic.med.osaka-cu.ac.jp
Kenei
K
Shimada
Takahiko
T
Kawarabayashi
Atsushi
A
Tanaka
Daiju
D
Fukuda
Yasuhiro
Y
Nakamura
Minoru
M
Yoshiyama
Kazuhide
K
Takeuchi
Tetsuya
T
Sawaki
Kazuaki
K
Hosoda
Junichi
J
Yoshikawa
D052242:Adiponectin; D001786:Blood Glucose / Q000032:analysis; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003094:Collagen / Q000097:blood; D003327:Coronary Disease / Q000097:blood*; D018592:Cross-Over Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008077:Lipoproteins, LDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D010316:Particle Size; D011446:Prospective Studies; D013662:Tea / Q000737:chemistry; D014280:Triglycerides / Q000097:blood
D052242:Adiponectin; D001786:Blood Glucose; D002784:Cholesterol; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D003094:Collagen; D006442:Glycated Hemoglobin; D036341:Intercellular Signaling Peptides and Proteins; D008077:Lipoproteins, LDL; D013662:Tea; D014280:Triglycerides