My patient was a 37-year-old executive assistant at a movie studio, and though I had known her for a long time, this was the first time she’d ever mentioned that she liked to eat paper. The craving, she told me, had been with her for years. Regarding it as an odd but harmless quirk, she hadn’t really shared her desire for paper with anyone before.
“Well, how much paper do you eat?” I asked. I didn’t want to embarrass her by suggesting some large amount, so I grabbed a scratch pad that I keep handy in my exam room, tore off a corner of a page, and held it up. “Like this much?”
She laughed. “Are you kidding? I could eat two or three of those pages at lunch. There’s a pad on my desk in my office, and I nibble all day long. And you know what else? I love the smell of cement, especially wet cement.”
She practically licked her lips as she told me this. “Sometimes I pause in the concrete stairwell at work just to enjoy the smell. Nuts, huh?” She giggled, certain I thought she was crazy.
Crazy was not what I was thinking. I was thinking pica. Pica is an eating disorder in which a person habitually eats nonnutritive substances at an age that is developmentally inappropriate. Up to 24 months of age, kids will put anything in their mouths, but by the time you’re an adult you are supposed to know better. Outside the pediatric realm, pica usually turns up in this country among adults with mental disabilities or psychiatric disorders. People have been documented to eat everything from dirt, clay, and hair to pebbles, cigarette butts, laundry starch, and feces. Patients with serious psychiatric conditions have ingested buttons, needles, coins, and even lightbulbs.
In many regions, however, pica can be a learned behavior. Eating white clay to treat morning sickness, for example, has been a practice in some rural African American communities. But my paper-munching patient wasn’t pregnant, nor was she developmentally disabled. She had never shown any signs of a psychiatric disorder.
I considered other reasons for her unusual craving. I recalled that certain nutritional deficiencies are associated with pica. Iron deficiency, in particular, can induce strange tastes, though it’s not known why. In any event, correcting the iron shortage fixes the problem. Interestingly, in most picas associated with known deficiencies, the substance being craved doesn’t even contain the missing mineral. As you might guess, there isn’t a lot of iron in a paper towel.
I drew blood for testing, and the results soon confirmed that my patient was low in iron. Why would that be? For a woman in her childbearing years, the most frequent reason is menstrual blood loss, and I presumed that this was the cause in my patient. After checking to make sure that she did not have any hard-to-detect bleeding in her intestinal tract, I prescribed an oral iron supplement and asked her to come back in two months. I told her I was certain that this would cure both her deficiency and her paper craving.
Alas, at our next meeting she told me she still had a penchant for paper, and a repeat iron test showed that she was still low in this vital mineral. She assured me that she had been taking the iron supplement. So why wasn’t she better? She was ingesting the iron, but apparently her body wasn’t absorbing it. Some conditions of malabsorption can lead to iron deficiency, but these are almost always associated with other symptoms, like diarrhea. Although my patient had never complained of intestinal problems, I decided to ask about her bowel habits. She told me they were normal and hadn’t changed for years.