TY - JOUR
T1 - Effects of timing of acute catechin-rich green tea ingestion on postprandial glucose metabolism in healthy men
AU - Takahashi, Masaki
AU - Ozaki, Mamiho
AU - Miyashita, Masashi
AU - Fukazawa, Mayuko
AU - Nakaoka, Takashi
AU - Wakisaka, Takuya
AU - Matsui, Yuji
AU - Hibi, Masanobu
AU - Osaki, Noriko
AU - Shibata, Shigenobu
N1 - Funding Information:
This work was supported by the Japan Society for the Promotion of Science (KAKENHI grant no. 26220201 to S.S.) and a research grant from the Kao Research Council for the Study of Healthcare Science (Grant no. A-61025 to M.T.).We would like to thank Editage (www.Editage.jp) for English language editing. This work was supported by the Japan Society for the Promotion of Science (KAKENHI grant no. 26220201 to S.S.) and a research grant from the Kao Research Council for the Study of Healthcare Science (Grant no. A-61025 to M.T.). M.T. M.O. M.M. and S.S. designed the research, analyzed the data, and wrote the manuscript; T.W. and Y.M. analyzed serum catechin concentrations, prepared the test beverages, and reviewed the manuscript; M.H. and N.O. reviewed the manuscript; M.T. M.O. M.F. and T.N. performed the experiments; and all authors read and approved the final manuscript. T.W. Y.M. M.H. and N.O. are employees of Kao Corporation. M.T. received a research grant from Kao Research Council for the Study of Healthcare Science. T.W. Y.M. M.H. and N.O. were not involved in the interpretation of the results. The rest of the authors have no conflicts of interest to declare.
Funding Information:
This work was supported by the Japan Society for the Promotion of Science (KAKENHI grant no. 26220201 to S.S.) and a research grant from the Kao Research Council for the Study of Healthcare Science (Grant no. A-61025 to M.T.).
PY - 2019/11
Y1 - 2019/11
N2 - Green tea polyphenols, particularly catechins, decrease fasting and postprandial glucose. However, no studies have compared the timing of green tea ingestion on glucose metabolism and changes in catechin concentrations. Here, we examined the effects of timing of acute catechin-rich green tea ingestion on postprandial glucose metabolism in young men. Seventeen healthy young men completed four trials involving blood collection in a fasting state and at 30, 60, 120, and 180 min after meal consumption in a random order: 1) morning placebo trial (09:00 h; MP trial), 2) evening placebo trial (17:00 h; EP trial), 3) morning catechin-rich green tea trial (09:00 h; MGT trial), and 4) evening catechin-rich green tea trial (17:00 h; EGT trial). The concentrations of glucose at 120 min (P=.031) and 180 min (P=.013) after meal intake were significantly higher in the MGT trials than in the MP trials. Additionally, the concentration of glucose was significantly lower in EGT trials than in the EP trials at 60 min (P=.014). Moreover, the concentrations of glucose-dependent insulinotropic polypeptide were significantly lower in the green tea trials than in the placebo trials at 30 min (morning: P=.010, evening: P=.006) and 60 min (morning: P=.001, evening: P=.006) after meal intake in both the morning and evening trials. Our study demonstrated that acute ingestion of catechin-rich green tea in the evening reduced postprandial plasma glucose concentrations.
AB - Green tea polyphenols, particularly catechins, decrease fasting and postprandial glucose. However, no studies have compared the timing of green tea ingestion on glucose metabolism and changes in catechin concentrations. Here, we examined the effects of timing of acute catechin-rich green tea ingestion on postprandial glucose metabolism in young men. Seventeen healthy young men completed four trials involving blood collection in a fasting state and at 30, 60, 120, and 180 min after meal consumption in a random order: 1) morning placebo trial (09:00 h; MP trial), 2) evening placebo trial (17:00 h; EP trial), 3) morning catechin-rich green tea trial (09:00 h; MGT trial), and 4) evening catechin-rich green tea trial (17:00 h; EGT trial). The concentrations of glucose at 120 min (P=.031) and 180 min (P=.013) after meal intake were significantly higher in the MGT trials than in the MP trials. Additionally, the concentration of glucose was significantly lower in EGT trials than in the EP trials at 60 min (P=.014). Moreover, the concentrations of glucose-dependent insulinotropic polypeptide were significantly lower in the green tea trials than in the placebo trials at 30 min (morning: P=.010, evening: P=.006) and 60 min (morning: P=.001, evening: P=.006) after meal intake in both the morning and evening trials. Our study demonstrated that acute ingestion of catechin-rich green tea in the evening reduced postprandial plasma glucose concentrations.
KW - Circadian rhythm
KW - Epigallocatechin gallate
KW - Glucose metabolism
KW - Incretin
KW - Meal timing
UR - http://www.scopus.com/inward/record.url?scp=85072207382&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85072207382&partnerID=8YFLogxK
U2 - 10.1016/j.jnutbio.2019.108221
DO - 10.1016/j.jnutbio.2019.108221
M3 - Article
C2 - 31522082
AN - SCOPUS:85072207382
VL - 73
JO - Nutrition Reports International
JF - Nutrition Reports International
SN - 0955-2863
M1 - 108221
ER -