Administration of 100mg caffeine or 475mg of C. annum capsules in male subjects 45 minutes after consumption of a high carbohydrate meal reduced blood glucose levels (BGL) to near fasting levels within 15 minutes, compared to the placebo, and increased energy expenditure over the 120-minute test period.
Writing in ‘Frontiers in Physiology’, they explain that intake of both compounds stimulated brown adipose tissue (BAT) activity to improve whole body glucose homeostasis and insulin sensitivity in healthy individuals and those with metabolic syndromes, such as type 2 diabetes mellitus (T2DM), and demonstrates the potential for individual dietary components to promote BAT activity.
“The significant results from this study may help in providing some clarity about the mechanisms,” wrote scientists from La Trobe University and the University of Melbourne.
Thermogenic properties
Caffeine is known to increase thermogenesis, but dosage is important because too much can induce adverse side effects, whereas an “acute” single dose (100mg) increases interscapular BAT temperature without causing harm, the authors explain.
Studies show that ingestion of a single 375mg caffeine capsule in healthy young men increases BAT activity and energy expenditure in individuals with high BAT mass, however the effects of extensive intake at a lower dose over several days has not been investigated.
Equally, research indicates the active component in C. annuum (capsaicin) stimulates BAT activity, imitating the effect of cold-induced thermogenesis. This results in increased adrenaline secretion and energy expenditure and reduced body fat in humans.