DOC News January 1, 2005
Volume 2 Number 1 p. 22
© 2005 American Diabetes Association
Caffeine and Oral Glucose Tolerance Test
Caffeine is a common biologically active food component that has been
recently implicated in acute insulin
resistance.
Researchers at the University of Guelph, Ontario, Canada, investigated the
effect of caffeine on glucose tolerance and insulin sensitivity responses
during an oral glucose tolerance test (OGTT) in obese men with type 2
diabetes. Two trials were conducted in a randomized double-blind study. Both
trials were conducted after withdrawal from caffeine, alcohol, exercise, and
hypoglycemic agents for 48 hours and an overnight fast. The subjects either
ingested a caffeine capsule or a placebo and 1 hour later the men began an
OGTT.
Caffeine increased serum insulin, proinsulin, and C-peptide concentrations
during OGTT relative to the placebo. Insulin levels were 25% greater after the
caffeine trial than after placebo ingestion. Despite this, blood glucose
concentration was also increased in the caffeine trial. After caffeine, blood
glucose remained elevated 3 hours after the glucose ingestion.
Researchers concluded that "despite elevated and prolonged
proinsulin, C-peptide and insulin responses after caffeine ingestion, blood
glucose was also increased, suggesting an acute caffeine-induced impairment in
blood glucose management in obese men with type 2 diabetes."
Robinson LE, Savani S, Battram DS, McLaren DH, Sathasivam
P, Graham TE: Caffeine ingestion before an oral glucose tolerance test impairs
blood glucose management in men with type 2 diabetes. J
Nutr 134:2528–2533, 2004.[Abstract/Free Full Text]
CiteULike 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
