Maize (corn) is a typical staple food: high in carbs, moderate in protein, low in fat. Carbs are absolutely needed for survival. A population without enough carbs is in a state of famine. Protein is the next most necessary macronutrient. But the cause of hunger, as distinct from famine, is insufficient protein and fat. Ordinary maize has too little protein and specifically too little lysine.
Quality Protein Maize (QPM) is an improved form of maize (corn) developed in the late 1980’s, but only now becoming widespread in cultivation. Quality Protein Maize (QPM) has more of the essential amino acids lysine and tryptophan, ample amounts of methionine, and a better distribution of its total protein among various essential amino acids, resulting in a better ‘bioavailability”, i.e. a more efficient use of the protein by the human body.
Maize is an important staple food in sub-Saharan Africa, where both the total number and the percent of undernourished persons is high. If QPM is substituted for ordinary varieties, the total protein in the grain is a little higher, but the percent of lysine and of tryptophan are significantly higher. Studies have shown that growing children eating QPM averaged 12% great height increase and 9% greater body weight increase compared to children eating ordinary maize.
Africa shares a unique relationship with maize (Zea mays). After its introduction from New World explorers, maize was quickly adopted as the cornerstone of local cuisine, especially in sub-Saharan countries. Although maize provides macro- and micronutrients required for humans, it lacks adequate amounts of the essential amino acids lysine and tryptophan. For those consuming >50% of their daily energy from maize, pandemic protein malnutrition may exist. Severe protein and energy malnutrition increases susceptibility to life-threatening diseases such as tuberculosis and gastroenteritis. A nutritionally superior maize cultivar named quality protein maize (QPM) represents nearly one-half century of research dedicated to malnutrition eradication. Compared with traditional maize types, QPM has twice the amount of lysine and tryptophan, as well as protein bioavailability that rivals milk casein. Animal and human studies suggest that substituting QPM for common maize results in improved health. [Emily T. Nuss and Sherry A. Tanumihardjo, Quality Protein Maize for Africa: Closing the Protein Inadequacy Gap in Vulnerable Populations]
Despite the above assertion, the amount of lysine is not exactly doubled. The same study indicates that QPM contains 9.8% protein and 0.408 g lysine per 100 g whole food. This works out to 4.16% lysine (as a percent of total protein). Common maize is 9.4% protein and 0.265 g lysine, which is 2.82% lysine (relative to total protein). This represents about a 54% increase in lysine. However, when we compare the percent lysine to the IOM ideal value (5.1% lysine), QPM is 81.5% of ideal, whereas common maize is 55.3% of ideal.
From this information, we can see that simple crop substitution can improve food security greatly. There is no need for additional land, or additional money, or additional training. The farmers who grow maize will still be growing maize. The cultivation of Quality Protein Maize is the same as for any other maize. The color and flavor are the same; the culinary qualities are excellent. There is no real obstacle to wider adoption of QPM in developing nations.
Moreover, some new varieties of QPM are under development that contain carotenes used by the human body to produce vitamin A. These varieties offer more protein, a better essential amino acid profile, and the carotenes needed to prevent vitamin A deficiency blindness.