ANTIGUA, Guatemala — Ra ú l is a happy preschooler, tumbling around among 4- and 5-year-olds, but something is off.

It’s not his behavior, for it’s the same as that of the other little kids. Rather, it’s his face. The baby fat is gone, and although he’s only 3 feet 5 inches tall, the height of an average 5-year-old, an older face seems grafted on.

Sure enough, Raúl turns out to be 9. Malnutrition has left his body and mind badly stunted. He’s one of almost one-quarter of all children worldwide who are stunted from malnutrition.

Here in Guatemala, almost half of children are stunted. In some Mayan villages, it’s 70 percent.

In another world, on the Upper East Side of Manhattan, the restaurant Serendipity 3 offers a $295 hamburger. Alternatively, it sells a $214 grilled cheese sandwich and a $1,000 sundae.