Pellagra, a vitamin deficiency disorder, is characterized by the four D's:" dermatitis, diarrhea, dementia and death.
Red, scaling skin in exposed areas is often the first symptom, followed by varying degrees of loose stools and nervous system symptoms that may include lethargy, confusion, inattention, aggression and erratic behavior. Death ensues if pellagra is untreated.
First described in Southern Europe in the 18th century, pellagra was linked to poverty and malnutrition. Further studies showed that victims, who were predominantly poor farmers or inmates in prisons and asylums, subsisted on a diet of polenta or boiled cornmeal. Eventually, many cases of pellagra appeared in the Southern U.S. in the late 1800s and extended into the 20th century.
For decades, cornmeal in various forms made up a major portion of the diet of poor people in the South. A man whose family had endured prolonged poverty in the 1930s described to me a daily diet of cornmeal mush with some occasional milk. Although he never heard the term "pellagra," he recalls classmates with rashes suggestive of the illness.
A heated debate raged between scientists who insisted that pellagra was dietary in origin and those who thought the disease was due to an infection. Not until the 1920s, when small doses of brewer's yeast were shown to cure pellagra, was the dispute settled.
We now know that pellagra most often results from deficient intake of the B vitamin niacin, also known as nicotinic acid or vitamin B3. Niacin plays a vital role in the body's energy production and nervous system development.
Pellagra may also occur in intestinal disorders which interfere with absorption of niacin and in severe alcoholism. Since 1942, niacin has been among the vitamins added to enriched flour. Niacin also is found in meat, poultry, eggs, tomatoes, leafy vegetables, whole grains and legumes such as lima and pinto beans. Corn is a poor source.
However, despite the long prevalence of a corn-based diet in Central and South America, pellagra did not occur there. In those cultures, ground corn was first boiled in lime water, a procedure which releases the small amount of niacin contained in the corn. In addition, beans traditionally accompanied tortillas made from the boiled cornmeal.
These days, pellagra and other vitamin deficiencies have been diagnosed among refugees who have fled civil wars in Somalia and Syria.
Malnutrition may have lifelong effects on victims as well as their descendants as shown in a Dutch study.
From November 1944 until liberation in May 1945, residents of the Netherlands endured a severe famine. Nazi authorities blocked food imports and flooded agricultural lands. A severe winter further limited food production. A careful, long-term follow-up of survivors and their descendants has yielded a number of surprises.
Prenatal exposure to famine led to a higher occurrence of obesity, high blood pressure and coronary disease in mid-life. Females exposed to severe malnutrition during their first trimester of pregnancy had an increased risk of breast cancer. Prenatal exposure to famine also led to higher incidences of depression, anxiety and schizophrenia. Males showed a higher incidence of anti-social behavior.
The term "epigenetics" refers to ways in which environmental factors alter the function of our genes. Sometimes these factors promote the addition of a chemical grouping to DNA, causing lasting change. Hormones such as cortisol, released in response to stress, may alter DNA activity over several generations. The Dutch study of famine survivors strongly suggests epigenetic influences.
No similar study exists for pellagra specifically and malnutrition more generally among Southerners growing up in sustained poverty. Vital statistics are lacking. I am unaware of any multi-generational follow-ups. The Dutch studies raise the possibility that obesity, high blood pressure and Type II diabetes, which affect residents of the Deep South disproportionately, might be due in part to malnutrition experienced by earlier generations
We should consider health problems of today as possible legacies of extreme poverty that occurred decades earlier.
Contact Clif Cleaveland at firstname.lastname@example.org.