By Will Ferguson, College of Arts & Sciences
A new study led by Caitlyn Placek, a Washington State University anthropology doctoral candidate, and Edward Hagen, associate professor of anthropology, suggests cultural beliefs and taboos play an important role in the puzzling food aversions of expectant mothers, perhaps even more than the natural immunological responses that have evolved over millennia.
In villages that dot the rural countryside of Tamil Nadu, India, for example, Placek found that pregnant women avoid fruit more than any other type of food, largely because of cultural beliefs that eating fruit can harm their unborn children.
Women in the region believe eating mangoes, black grapes, papaya and other fruits while pregnant causes miscarriage and premature birth, as well as manthai, a disease characterized by black or blue patches on an infant’s skin, Placek said.
Her study shows that pregnant women often learn from others what foods to avoid, rather than relying solely on their own negative reactions to various foods.
“Our results suggest the sharing of cultural beliefs about food may play a stronger role in pregnancy’s puzzling food aversions than previously thought,” she said.
Testing evolutionary theory
Previous studies have concluded that pregnant women’s distaste for certain foods and the nausea, vomiting and discomfort that goes with eating them are the body’s way of protecting a developing baby from plant toxins and foodborne pathogens.
However, this hypothesis has been difficult to confirm in studies conducted in the United States and other countries where the risk of foodborne illness is low and a wide variety of foods are available at the local supermarket.
“In rural India, you simply can’t go to Safeway and pick out a healthy and nutritious snack,” Placek said. “We thought the lack of available options would make it easier to test evolutionary theories regarding foods women were craving or avoiding and what was motivating their decisions.”
Forty percent of women in the study reported an aversion to fruits, claiming they had been told or had learned through experience that eating fruit during pregnancy can cause stomach pain, miscarriage or manthai. Twelve percent of respondents said meat should be avoided and less than 5 percent claimed an aversion to vegetables.
Allergies may explain fruit avoidance
One possible yet unexplored immunological explanation for Indian women’s aversion to fruit while pregnant is that many fruits are potential allergens, especially for individuals allergic to latex. An extreme allergic reaction to the latex in a papaya or unripe mango during pregnancy could be potentially catastrophic for a mother or her unborn child.
This is one of many uncertainties Placek will address next spring when she returns to India. She also plans to work with Indian health officials who are interested in reintroducing fruit into the diets of pregnant women suffering from malnutrition.
“The officials I have talked to are really interested in this research because many of these women are very food insecure but are nevertheless avoiding highly nutritious foods – foods they have access to and that are potentially beneficial to their babies,” she said.