Why can diets based mostly on corn lead to pellagra?

Diets based primarily on corn can lead to pellagra due to two primary nutritional factors:

• Bound Niacin: The niacin present in corn is in a bound form that the human body cannot effectively digest or absorb. Historically, Native American populations prevented this deficiency by soaking corn in lime water, a process that frees the bound niacin.12
• Low Tryptophan Content: Unlike many other foods, corn is low in the amino acid tryptophan. Because the body can convert tryptophan into niacin, a diet lacking sufficient high-quality protein—which provides the necessary tryptophan—increases the risk of developing the disease.13

Pellagra is characterized by the "four Ds": dermatitis, diarrhea, dementia, and death. It is effectively prevented or treated through a well-balanced diet that includes protein-rich foods, such as milk or eggs, which provide the tryptophan required for niacin synthesis.13