I never saw this before but the answer is found in the Bible.
Proverbs 11:25 says, “The liberal soul shall be made fat.”
Liberalism causes obesity.
And since liberalism is on the rise, it stands to reason that there is more obesity.
Incidentally, everyone agrees that it is not nice to make fun of fat people so, therefore, I guess I should stop making fun of Liberals.
P.S. *All things being equal, fat people use more soap.