A small cohort of healthy adults experienced an increase in brown adipose tissue activity, measured via thermal imaging, after consuming coffee when compared with the response measured after consuming water, suggesting that caffeine may promote weight loss, according to findings published in Scientific Reports.
Brown adipose tissue rapidly generates heat and metabolizes macronutrients such as glucose and lipids through the activation of mitochondrial uncoupling protein 1 (UCP1), Michael E. Symonds, PhD, a professor at the University of Nottingham School of Medicine, United Kingdom, and colleagues wrote. Diet can modulate UCP1 function, they noted, but the capacity of individual nutrients to promote the abundance and activity of UCP1 is not well established.
“This is the first study in humans to show that something like a cup of coffee can have a direct effect on our brown fat functions,” Symonds said in a press release. “The potential implications of our results are pretty big, as obesity is a major health concern for society and we also have a growing diabetes epidemic and brown fat could potentially be part of the solution in tackling them.”
The researchers examined the effect of caffeine on brown adipose tissue thermogenesis in vitro and in vivo. In stem cell-derived adipocytes exposed to caffeine, the researchers observed increased UCP1 protein abundance and cell metabolism with enhanced oxygen consumption and proton leak.
“These functional responses were associated with browning-like structural changes in mitochondrial and lipid droplet content,” the researchers wrote.
Symonds and colleagues then analyzed data from nine healthy adults with a normal BMI (five women; mean age, 27 years; mean BMI, 23 kg/m²) who were instructed not to consume caffeine or alcohol or perform vigorous exercise within 9 hour before baseline imaging, which included thermally reflective skin markers. The participants then consumed a caffeinated beverage (Nescafe; 65 mg caffeine) or water and remained seated for 30 minutes to allow time for caffeine absorption, before undergoing further imaging to trace brown adipose tissue reserves.
Researchers found that drinking coffee, when compared with water, stimulated the temperature of the supraclavicular region, which co-locates to the main region of brown adipose tissue, indicative of thermogenesis.
“From our previous work, we knew that brown fat is mainly located in the neck region, so we were able to image someone straight after they had a drink to see if the brown fat got hotter,” Symonds said in the release. “The results were positive and we now need to ascertain that caffeine as one of the ingredients in the coffee is acting as the stimulus or if there’s another component helping with the activation of brown fat.”
Symonds said the researchers are now looking at caffeine supplements to test whether the effect is similar.
“Once we have confirmed which component is responsible for this, it could potentially be used as part of a weight management [regimen] or as part of glucose regulation program to help prevent diabetes,” he said in the release. – by Regina Schaffer
Disclosures: The authors report no relevant financial disclosures.