The leading hair signs of nutrition-related disorders are thin hair, dyspigmentation (specifically lightening), alopecia, and decurling and brittle hair. Eighty percent of children with kwashiorkor or marasmus have at least one hair sign, and hypopigmentation and thinning are most common. The flag sign occurs when altering light and dark bands are visible within single hairs on the scalp (Fig 1). The lighter colored hairs are thought to be hair growth during periods of malnutrition, but details of the cause of this sign and generalized hypopigmentation are not known.