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/ Source: TODAY
By Erica Chayes Wida

Jimmy Fallon's iconic teenaged character Sara may love saying "Ew!" to pretty much everything. But in real life, "The Tonight Show" host really can't stand one of America's most popular condiments: mayonnaise.

The rich, gelatinous spread has certainly freaked out some foodies in the past. For many, mayo's texture, taste and smell are all a turnoff.

But Fallon's disgust stems from one miserable mayonnaise-y experience that occurred in his childhood ... and it still haunts him to this day.

On Thursday, Fallon and his "Tonight Show" guest, model Kendall Jenner, discussed their least favorite foods. Jenner disclosed that she hates bananas (just like Ree Drummond!) because when she was growing up, her father Caitlyn Jenner ate them all the time (hey, Olympic athletes need their potassium).

Fallon, shocked as to how anyone could dislike the delicious fruit, countered his guest's food aversion with the most squeamish story imaginable.

Kendall Jenner and Jimmy Fallon discuss their food aversions on Thursday's episode of "The Tonight Show." (Photo by: Andrew Lipovsky/NBC)NBC

Fallon explained that when he was growing up, he often played on the stoop in his backyard, which was guarded by a metal railing. One day, a young Fallon decided that he just had to squeeze his head through the iron bars, ya know, just to see what would happen.

What happened next probably won't surprise many people. "And I got stuck! And so my head was stuck," Fallon said. "So my grandma was like, 'We got to get him out of there. Let's grease him up.' So she rubbed mayonnaise all over my head."

As if being drenched in globs of mayo wasn't enough, Fallon went on to explain that it got even worse.

Jimmy Fallon can't face mayonnaise without saying, "Ew."YouTube

"And it's like 95 degrees out," Fallon continued.

So, poor little Jimmy's head was slathered in mayo and he continued to roast away in the summer heat ... all while being tugged and prodded by his dear ol' granny until he was finally set free.

It's pretty safe to say Fallon won't be enjoying a serving of Alton Brown's mayo-slathered steak or the viral peanut butter and mayo sandwich anytime soon. Or ever.