Another 3.5 million children lack sufficient iodine, which can lower a child's IQ by 10 or more points. More than a half million suffer vitamin A deficiency, which cripples young immune systems; merely ensuring adequate vitamin A can lower child mortality by more than one-fifth. Children lacking vitamin B12 have impaired cognitive skills and do poorly on tests.
In most foods, these vital nutrients exist in traces. Denied them in the womb and in infancy, children suffer irreversible brain and nervous-system damage, even if they appear well fed.
"Even trained people can't always see them," said Mark Fryars, the director of program services for the Micronutrient Initiative. "You may see a kid whose skin is very pale. You may go into a classroom where a child wanders off, or falls asleep, or doesn't go out to play because he's too tired. Multiply that into whole villages, and that translates into an impact on the society."
In richer parts of the world, nutritional deficiencies are a nonissue. Three percent of American children are malnourished. American flour and cereals have been fortified with vitamins and iron -- by law -- since the 1930s.
In sub-Saharan Africa, however, lost productivity from vitamin and mineral deficiencies costs nations $2.3 billion a year, UNICEF reports, and losses of productivity in Mozambique, Zambia and Malawi exceeded 1 percent of gross domestic product.
Many African children sometimes receive nutrient supplements, courtesy of the World Food Program, UNICEF and charities. Still, donors cannot meet the need. In Ethiopia, for example, a venture between the government and U.N. agencies is caring for 20,000 acutely malnourished children in 100 locations.
"But we can count 70,000," said Iqbal Kabir, the chief nutrition expert at UNICEF offices in Addis Ababa, Ethiopia's capital. "We can't treat them all."
Shimider is but a hundred or so stone and reed homes, one room each, in a mountain valley in the Amhara region, 250 miles north of Addis Ababa. Amhara's slopes have been intensively farmed for thousands of years, and their soils are exhausted.
Twenty-two years ago, a famine here killed more than 1 million people. Today, hunger is measured in squandered lives. Thirty percent of Amhara's children under 5 are stunted, with another 26 percent severely stunted, evidence of lifelong, acute hunger.
One recent Sunday, Tewres Beram, a woman in her early 20s, carried her daughter Mekdes to a free immunization clinic. Mekdes, severely malnourished, sat suckling fruitlessly at her mother's breast. "We don't have enough food," her mother said, "so there's not enough milk to feed her." A year old, Mekdes does not crawl. Her sister, 2, has barely begun to crawl. "Both of them are like little dead bodies," their mother said.
Sirkalem Birhanu, 40, clasps Endalew, age 2 and unable even to hold up his head. "He's always sick," she said.
And there is Berhane Gebeyew, 36, whose malnourished 18-month-old daughter, Genet, is a lump in her lap, despite receiving six months' worth of fortified food in May from the government.
Gebeyew split the food among Genet and her four siblings, ages 6 to 15. "The other children, when they stare at my eyes, I give it to them," she said.
She and her husband feed their children two daily meals of injera, a spongy flatbread of fermented barley, occasionally with 4 ounces of bean sauce. When the children attend Shimider Primary, each gets 10 ounces of vitamin-fortified meal mixed with cooking oil. But attendance is spotty, especially when they help harvest crops in November and December.
And by the time children reach school age, much of malnutrition's damage has been wrought.
Wondewosen Fekadu is the headmaster at Shimider Primary. Fekadu worked last year in Tseta, a lowland village where families eat better and drink milk. The difference in their students, he said, is striking. "Children there are relatively smarter and more active," he said. "There are students here who are up to fourth grade, and they cannot even read and write, even attentively following the classes."
Three of Gebeyew's children attend Shimider Primary. Mogus, a 10-year-old third grader, is 31/2 feet tall -- wide-eyed, sweet and flummoxed by academics.
"He's on the poor level -- very slow," his teacher said. "He doesn't give attention when I'm teaching. He doesn't concentrate." In a classroom of 60 children, Mogus ranks 46th.
Mulu, 13, her ribs prominent through rips in her dress, races from home to get to her beloved third-grade class. But Mulu is 47th in a class of 60.
Fifteen-year-old Yirgalem, perhaps 2 inches taller than Mulu, has a teenager's diffidence toward school. "It's not that tough," he said. His teachers differ. "When he comes to school, I don't even think his mind is normal," one of his teachers, Amelework Ejigu, said.
At Tefera Hailu Memorial Hospital in Sekota, across a mountain from Shimider, the nutrition ward's 10 beds are filled with worried mothers and shrunken babies. Among them are Adna Berhanu and her 5-month-old son, Agnecheu.
Berhanu's skeletal baby is severely iodine deficient, surely impaired for life should he survive. Although iodine deficiency is endemic in Amhara province, "I've been here a year, and we have no iodine in this ward," the nurse on duty said. Beyond a blood test to estimate iron content, the attending physician said, no one analyzes children's nutritional status. Such tests, he said, are luxuries.
"We focus on saving lives; that's our long-term focus," he said. "We can't focus on what happens to them afterward."