The Ecphorizer

I knew that it would happen,
For years my greatest fear.
Scientists have determined,
"Cancer is caused by beer."

In twenty tests conducted
Since nineteen twenty-three,
Rats drank beer four times a day;
Now, none are cancer-free.

Perhaps I need not worry
I'm thirty-eight, you know
Rats took nearly sixty years;
I've twenty-two to go.

Then, too, to my advantage,
The rats I far outweigh.
For me to drink a like amount
Requires a keg each day.