'Tell me," a successful French chef asked me recently. "Is it true that Americans eat at least one meal a day in their cars?"
Like almost everything the Europeans believe about Americans, this is both true and untrue. We like our drive-through, yes, but not quite (I hope) once a day. I tried to explain this. We're an automobile culture, I said. To us, cars symbolise freedom and vitality. And we're always in a hurry to see things and do things and in a country of such vast open spaces, eating in the car just seems natural.
He still seemed troubled by this. Europeans - especially the French - often zero in on this particular American habit when trying to figure us out. It's bewildering to them why anyone would chose to drive and eat at the same time, when both of those things are so pleasurable by themselves. It seems almost decadent to them, even shameful.
"But would it not be possible", he said after a moment, "to stop the car and maybe get out of the car and eat at a table and then get back in the car and continue driving?"
"I guess so," I said.
He nodded. "Yes, I think that would be better. Maybe then you would not all be so terribly fat."
The patriot in me wanted to respond to this insult with something equally withering. Something about certain former directors of the International Monetary Fund, or maybe a sarcastic mention of the speed with which Hitler's tank divisions made the trip from Berlin to Paris.
But Americans are fat. Groaningly so, in many cases.
If you could build a time machine and go back in time - not far, say 50 years - and you told the first American you saw that in the future, man would walk on the moon, we'd all carry video telephones the size of a deck of cards, and that poor Americans would be fat, I guarantee you the response would be: "Wow! Really? Poor people are fat?"
Because, of course, poor people are supposed to be skinny. They're poor. But the astonishing rise in standards of living since the 1950s, coupled with advances in food preservation - not to mention the brilliant invention of the triple cheeseburger - have meant that the once universal indicator of wealth, the big belly, is now an indicator of the working class.
Rich people in America today look like old photographs of poor people during the Great Depression. Poor people today look like the corpulent, trouser-bursting cartoon sketches of the Robber Barons of the 1890s. The stereotypes still apply, only in reverse.
I didn't bother explaining this to my chef friend. Instead, I decided to ignore his (rather accurate) characterisation of the American waistline and bring him up to date on the rest of the world.
China, I told him, is getting fat, too. Slowly, of course - China's billions move at a glacial pace, but like a glacier, once they're moving they're impossible to turn around - yet as the country gets richer and pulls itself out of poverty, the inevitable happens. People discover the joy of fatty snack foods.
One of the most popular fast food restaurant chains in China is Kentucky Fried Chicken. A huge part of its success, though, is that it sells food well outside of the traditional American KFC menu. Aside from the famous buckets of fried chicken, the Chinese KFCs offer local flavours like chicken wraps and spicy tofu rice.
China's economy grew about 10 per cent last year, but apparently its belt size grew even faster. The Shanghai Daily reported this week that obesity in local children is up a whopping (or should I say "Whopper"?) 25 per cent. The usual suspects are rounded up: fast food, television, soft drinks and insufficient exercise. But the true root cause of all of this swelling is that people who once worried about not getting enough to eat are now awash in food choices, most of them fried. If you grew up hearing stories from your parents and grandparents about the Great Depression (if you grew up in the United States) or the Great Famine (if you grew up in China), the moment the buffet opens you're bellying up to the fry station and loading up on the carbohydrates.
The good news for the Chinese is that they're all getting richer, that the Chinese standard of living is rising. The bad news is, they're going to get as fat as the Americans are. There are already one billion and more Chinese people in China. If each one gets twice as large, they're going to need a bigger country.
Rob Long is a writer and producer based in Hollywood