Amber Wilcox-O’Hearn explains why.
Your heart beats 100,000 times a day, every day, without rest. You’d think it needs a reliable energy source, and you’d be right. One of Amber’s references (#4) reminds me that, “Fatty acids are the heart’s main source of fuel, although ketone bodies as well as lactate can serve as fuel for heart muscle. In fact, heart muscle consumes acetoacetate in preference to glucose.”
Steve Parker, M.D.
Diabetic Mediterranean Diet 
thank you Dr. Parker. This has been a most interesting response. I was amused about the discussion about alcohol. I saw somewhere else some other commentator made the comment that all animals from the fruit fly to the elephant can metabolize ethyl alcohol. And that elephants would routinely knock over a winery/brewery for the booze in India.
Jim, I understand many horses enjoy beer, too.
Refresh my biochem, how does one produce more acetoacetate?