Old man

A woman walked up to an elderly man rocking in a chair on his porch.

"I couldn't help noticing how happy you look" she said. "What's your secret for a long, happy life?"

"I smoke three packs of cigarettes a day" he said. "I also drink a case of whiskey a week, eat fatty foods and never exercise".

"That's amazing" the woman said. "How old are you?"

Spoiler:

"Thirty-six".