Somebody finally asked it. It’s the question that has been bottled up inside bananas for decades.

Why is the phrase “You’re a peach!” considered a compliment and “You’re bananas!” an insult?

Reddit user Leeisamoron presented this perplexing question to Reddit’s Explain Like I’m Five community.

Let’s face it: Bananas are like that nice guy you can’t get rid of. They’re dependable, predictable, forever-in-season and just always there. But how did they become associated with deranged human tendencies?

Reddit user lieman responded that while the exact origin of the phrase “going bananas” is unclear, according to Dan Koeppel, author of Banana: The Fate of the Fruit That Changed the World, the first known usage of the term has been credited to a 1968 academic publication, which documented that Kentucky college students were saying it.

Writes Koeppel, “… it was during the late 1960s that rumors spread across university campuses that roasted banana peels had psychedelic properties, and that ingesting them could lead to hallucinations similar to ones brought on by LSD or psilocybin (“magic”) mushrooms. (It isn’t true, folks.)”

Yet it is possible that “bananas” itself, sans the verb, was tied to mental incapacity even before that. Koeppel notes that in 1957, a newspaper in Ohio used the term “bananas” to describe a crazed lawbreaker.

How, then, did the peach become the darling of the fruit world, instantly associated with a kind and pretty woman? Redditor lieman dug up this passage about the sexual connotations of the fruit in the Encyclopedia of Word and Phrase Origins by Robert Hendrickson:

“Peaches were the ‘Percian apples’ of the ancient Romans. … The fruit, luscious to look at, touch, and taste, has been described as a pretty young girl at least since the ancient Chinese used it as slang for a young bride.”

In a discussion on the Phrase Finder website, a commenter noted that a fair-skinned woman has been referred to as “a peach” since the Civil War because her complexion looks like “peaches and cream.”

The phrase eventually made its way into pop culture. “You’re the Boss,” a 1961 song written by Jerry Leiber and Mike Stoller, and later recorded by Elvis Presley, included the lyrics, “You’re a peach, you’re a plum / You’re a diamond, you’re a pearl / You’re the best of everything.”

Meanwhile, this guy over here is saying, this shit is B-A-N-A-N — well, you know.