"Pumpernicke and sex" joke

There were these two 95-year-old men sitting at the senior center one day when the one states, "I have to get right home!"

"What's your hurry?" asks the other.

"Me and the wife are having sex again today."

"Again? How often do you have sex?"

"Every day! I don't have time to talk but I'll tell you what the secret is - Pumpernickel Bread." And he scurried off.

As the other old guy was walking home, he passed a bakery and wandered in. "Do you have any Pumpernickel Bread?" he asked the lady behind the counter.

"Yes, we have 3 shelves of Pumpernickel Bread."

"I'll take it all," the old man blurts out.

The lady was surprised and says, "All of it? It will get hard."

The old man replies, "Why does everyone know about this but me?!"