Saturday, February 20, 2010

Is your coffee making you fat?

I apologize for the melodramatic title, because I really don't think coffee makes you fat. Now the overabundance of sugar, milk, cream and syrups that Americans typically partake in along with plain ole coffee is another story entirely.  But for the purposes of this post let's talk only about black coffee or more specifically, caffeine.

Adenosine is an important nucleoside involved in (one of its many roles of cellular signaling) insulin signaling and glucose uptake and disappearance.  Caffeine happens to be an adenosine receptor antagonist; this means that caffeine will block the actions of adenosine.  In this case, we are considering its specific actions on adenosine that effect insulin signaling and glucose transport.

So what does it all mean?  Below is a study published in Diabetes in October 2001.  Don't worry, the science still applies to today.  The findings of the study?  Apparently caffeine decreases glucose disposal and suggests that adenosine plays a role in regulating glucose disposal in resting humans.  So caffeine can have a blunting effect on insulin sensitivity, thus inhibiting your body's ability to take glucose and use it for energy as effectively as possible. 


So should you eliminate caffeine completely from your daily routine?  I'm not going to eliminate it from my diet.  A black coffee or Americano is essential to my existence (well, not really).  Should you take breaks from caffeine every once in a while?  It's probably not a bad idea.  However, there are benefits to caffeine, but we'll save that for another day.

Will caffeine make you fat?  I'm going to go out on a limb and say...NO!  But I think it's always important to know exactly how things that you ingest can impact your overall health and fitness.


Until next time...

1 comment:

  1. Good post!

    I question the perspective of this paper's conclusion, though. The fact that caffeine increases plasma epinephrine may stimulate greater fat mobilization and utilization as the alternative energy source, potentially decreasing the uptake and burning of glucose. This plasma glucose, therefore, may not necessarily mean decreased insulin sensitivity, but a temporary alternative source of energy might have been stimulated -- stored fat. This makes sens, as there is a lot of evidence of caffeine's enhancement of fat metabolism.

    But physiology is tricky, and it's hard to know what else caffeine might be doing -- however, like you, I'll stick to my Americano!