The other thing I ask people to think about is coffee with caffeine. There’s a significant study in the European Journal of Clinical Nutrition, that took a group of young adults and half got coffee with caffeine and the other half had coffee without caffeine. The group that drank the coffee with caffeine had injury and impairment to the lining of their arteries and their blood vessels. So, you can still have coffee, but we would prefer that it be without caffeine.
-Dr. Esselstyn, here.
Here is the study to which I think Dr. Esselstyn refers. Here are the conclusions of that study, at least in what I take to be the abstract:
CC [caffeinated coffee as distinguished from decaf] acutely induced unfavorable cardiovascular effects, especially on endothelial function. In the fasting state, insulin secretion is also likely reduced after CC ingestion. Future studies will determine whether CC has detrimental clinically relevant effects, especially in unhealthy subjects.
What is "endothelial function?" Wikipedia describes endothelial dysfunction in part as follows:
Endothelial dysfunction is a systemic pathological state of the endothelium (the inner lining of blood vessels) and can be broadly defined as an imbalance between vasodilating and vasoconstricting substances produced by (or acting on) the endothelium. Normal functions of endothelial cells include mediation of coagulation, platelet adhesion, immune function and control of volume and electrolyte content of the intravascular and extravascular spaces. Endothelial dysfunction can result from and/or contribute to several disease processes, as occurs in septic shock, hypertension, hypercholesterolaemia, diabetes, it can also result from environmental factors, such as from smoking tobacco products and exposure to air pollution.