High Caffeine Levels May Lower Body Fat, Type 2 Diabetes Risks
Higher blood caffeine levels appear to reduce the risks for both adiposity and type 2 diabetes, the results of a new study suggest.
Explaining that caffeine has thermogenic effects, the researchers note that previous short-term studies have linked caffeine intake with reductions in weight and fat mass. And observational data have shown associations between coffee consumption with lower risks of type 2 diabetes and cardiovascular disease.
In an effort to isolate the effects of caffeine from those of other food and drink components, Susanna C. Larsson, PhD, of the Karolinska Institute, Stockholm, Sweden, and colleagues used data from studies of mainly European populations to examine two specific genetic mutations that have been linked to a slower speed of caffeine metabolism.
The two gene variants resulted in “genetically predicted, lifelong, higher plasma caffeine concentrations,” the researchers note “and were associated with lower body mass index and fat mass, as well as a lower risk of type 2 diabetes.”
Approximately half of the effect of caffeine on type 2 diabetes was estimated to be mediated through body mass index (BMI) reduction.
The work was published online March 14 in BMJ Medicine.
“This publication supports existing studies suggesting a link between caffeine consumption and increased fat burn,” notes Stephen Lawrence, MBChB, Warwick University, UK. “The big leap of faith that the authors have made is to assume that the weight loss brought about by increased caffeine consumption is sufficient to reduce the risk of developing type 2 diabetes,” he told the UK Science Media Centre.
“It does not, however, prove cause-and-effect.”
The researchers agree, noting: “Further clinical study is warranted to investigate the translational potential of these findings towards reducing the burden of metabolic disease.”
Katarina Kos, MD, PhD, a senior lecturer in diabetes and obesity at the University of Exeter, UK, emphasized that this genetic study “shows links and potential health benefits for people with certain genes attributed to a faster [caffeine]…metabolism as a hereditary trait and potentially a better metabolism.”
“It does not study or recommend drinking more coffee, which was not the purpose of this research,” she told the UK Science Media Centre.
Genome-Wide Association Study Demonstrates Links
Using Mendelian randomization, Larsson and colleagues examined data that came from a genome-wide association meta-analysis of 9876 individuals of European ancestry from six population-based studies.
Genetically predicted higher plasma caffeine concentrations in those carrying the two gene variants were associated with a lower BMI, with one standard deviation increase in predicted plasma caffeine equaling about 4.8 kg/m2 in BMI (P < .001).
