I’m 61, and I saw ads when I was a kid that implied Wheaties would give you strength. At that time, Cheerios was making a similar pitch, “He’s feeling his Cheerios.”
Wheaties still has current athletes on the box. The last ad I remember with somebody saying “You better eat your Wheaties!” was retiree Michael Jordan.
I’ve always heard a martini is the breakfast of champions. 
I know it well Twicks. Then again I am also an Olde Pharte.
Yeah, it’s a marketing catchphrase for cereal, usually uttered by whatever pro athlete they’ve hired to shill for them that week.
Is “eat your Wheaties” a meaningful phrase? Odd that you would ask, I just used it this morning.
A slab, or slice, or chunk of?
Nah. Yer both wrong. Breakfast of Champions? Cold pizza and warm beer equals college student. Along with those 70s Saturday morning cartoons, of course.
We’d say it about weetbix which is a different breakfast food altogether but the similarity between the names ensures I’d know what you were talking about.
I hanker for a hunk of cheese.
Breakfast of Champions? From the 70s?
Why, that would be Little Chocolate Donuts!
I remember it from the commercials in the 70s.
I also just used it the other day, to a store cashier in reference to the already burgeoning holiday shopping crowd, “You better make sure to eat your Wheaties.”
She appeared to be around 30 and understood what I meant.
Sigh, my google-fu is weak, but I’m remembering a Jello pudding commercial with Bill Cosby where one of the kids says ‘you com out of there, old weird Harold.’ Or maybe I’m just imagining it.
On Bill Cosby’s early album titled Wonderfulness Old weird Harold is one of his friends. In “Go Carts” Old Weird Harold is his friend who stole the extra baby carriage wheel because his go cart was a Continental.
I answered yes and that I’m 41…and I’ll add that when I was ten the only people who would have said that phrase to me were 40+, and so I wouldn’t expect to hear it from anyone under 70.
I’m in my 40’s and I don’t recall it, though I’m familiar with the phrase, often said to a grouchy person, “Who peed in your Wheaties this morning?”
Keys go here, and fingers go here, but smart little buddies know they don’t go here!
Wait, that’s… not how I expected it to sound.
I have now used the phrase in question twice today.
Nine minutes to midnight; that’s probably it for today.
It took me a bit to remember what it meant, but I did at least know about the phrase.
Around here it’s always been, “Who pissed in your Corn Flakes this morning?” A matter of taste I suppose.