Paragh Khanna in Pyongyang is a marriage made in fuckwit technocrat heaven - the airport in one of the world's poorest countries is so easy to clear - and as such normally worth ignoring. But this bit was especially repellant
Most of those labeled defectors into China are actually economic migrants, and even in Pyongyang one can tell which children come from poor villages by their ragged sandals and brownish hair, made lighter by long hours under the sun in the fields.
A light or reddish tinge in the hair of normally dark-haired children is evidence of chronic malnutrition, not a consequence of some spartan, austere but basically productive agricultural regime. In a North Korean context it's likely to come from protein deficiency through subsisting almost entirely on corn porridge. Khanna's explanation sounds like something his minder told him, which he then went on and puinted to CNN's readers.