There must be teenagers who eat a full English before catching the bus to school. But I don't know any of them.
Breakfast and teenagers don't mix because they find it so hard to wake up. By the time they're standing in the kitchen, hair on end, clothes on backwards, they've only got two minutes before they have to leave the house.
"I take him breakfast in bed," says one mother shamefacedly. "Two Weetabix and a glass of orange juice. That way I know he's got something in his stomach to keep him going till lunchtime."
Another friend makes her 14-year-old a sandwich to eat at break. "But it's got to be soft white bread. She won't eat anything that needs chewing."
If you don't like the idea of all this mollycoddling, you can try to make sure your teenagers get downstairs in time to eat a piece of toast. But you'll have to have lungs like foghorns - or a bucket of icy water.
Even once you've got them sitting at the table, you can't control what they do. My younger son eats so slowly that his Shreddies go flabby and disintegrate, and he ends up staring in puzzled surprise at a bowl of lumpy brown milk.
In our house, the worst offender is my 17-year-old daughter, who gets from bed to front door in about ten minutes, and looks at me as if I'm insane if I suggest she might like to eat some porridge.
"I haven't got time!" she says.
"Well, take a banana."
"I don't want a banana."
"You've got to eat something," I wail, following her out to the hall.
"I'll buy something on the way."
"Have you got any money?" I shout after her as an icy blast from the open door hits me in the face.
There's no answer.
This is the problem: when you're a teenager, you can do incredibly mean and nasty things to your body and still wake up every morning glowing with health.
By the time you reach my age, breakfast is an imperative. Otherwise you'd probably be dead by lunchtime.