How did cornmeal contribute to nutritional deficiencies during the Great Famine?

During the Great Famine, the British government imported corn (maize) from the United States as a relief measure to help avert starvation. However, the Irish population’s reliance on this cornmeal contributed to significant nutritional deficiencies.1

Corn is inherently low in the amino acid tryptophan, which the human body requires to synthesize niacin (vitamin B3). Furthermore, the niacin present in corn is largely in a bound form that is difficult for the body to absorb. When a diet consists predominantly of corn without sufficient protein-rich foods to provide necessary tryptophan, individuals are at high risk of developing pellagra. This nutritional disorder is characterized by the "four Ds": dermatitis, diarrhea, dementia, and death.234

While traditional methods such as soaking corn in lime water can free bound niacin and prevent these deficiencies, this practice was not utilized in the relief efforts provided to the Irish peasantry. Consequently, the reliance on this nutritionally inadequate substitute intensified the suffering of those already facing extreme deprivation.41