There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
In humans caffeine stimulates thermogenesis by unknown mechanisms and its effect on
body weight has not been studies. The effect of placebo and 100, 200, and 400 mg oral
caffeine on energy expenditure, plasma concentrations of substrates and hormones,
blood pressure, and heart rate was investigated in a double-blind study in healthy
subjects who had a moderate habitual caffeine consumption. Caffeine increased energy
expenditure dose dependently and the thermogenic response was positively correlated
with the response in plasma caffeine (r = 0.52; p less than 0.018), plasma lactate
(r = 0.79; p less than 0.000001), and plasma triglyceride (r = 0.53; p less than 0.02).
Stepwise regression analysis with the thermogenic response as the dependent variable
excluded plasma caffeine and yielded the following equation: thermic effect (kcal/3
h) = -0.00459 X heart rate + 0.30315 X (triglyceride) + 0.53114 X (lactate) + 15.34
(r = 0.86; p = 0.0001). The results suggest that lactate and triglyceride production
and increased vascular smooth muscle tone may be responsible for the major part of
the thermogenic effect of caffeine.