Food Fears: Culture affects maternal diets
A pregnant woman’s relationship with food isn’t only about what she wants. It’s also about what she doesn’t.
A new study led by Caitlyn Placek, anthropology doctoral candidate, and Edward Hagen, associate professor of anthropology, WSU Vancouver, 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. Conversely, many women reported that unripe mangoes and other sour food items are among the most craved during pregnancy.
“The paradox was that the most-avoided food category often was the most craved,” Placek said. “The women recommended not eating highly nutritious and desirable fruits but generally did not have a problem with consuming meats and vegetables that are known to carry foodborne pathogens. Our results suggest the sharing of cultural beliefs about food may play a stronger role in pregnancy’s puzzling food aversions than previously thought.”
Testing evolutionary theories
Placek made the 8,000-mile trip from Washington to Tamil Nadu to study pregnancy-related food aversions in a society where resources are scarce and rates of infectious disease are high.
“Her results confirm that pregnant women do avoid foods they believe are harmful to their babies, even when food is hard to come by,” Hagen said.
Placek’s study also shows that pregnant women often learn from others what foods to avoid, rather than relying solely on their own negative reactions to various foods. 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 eatables 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.”
Two groups of women were surveyed for the study. The first group consisted of non-pregnant women whom Placek and a translator recruited by going door-to-door in and around Tamil Nadu. The second group consisted of soon-to-be mothers identified with the help of local health officials.
All participants were asked about cravings and aversions during pregnancy as well as why they wanted or avoided certain foods.
Forty percent 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.
Only 12 percent of respondents said meat should be avoided and less than 5 percent claimed an aversion to vegetables.
“Cultural preference is an interesting thing,” Placek said. “For instance, in Northern Peru researchers found that dark-colored fruits are considered cooling and healing rather than harmful. A big part of this research going forward will be resolving this apparent paradox.”
Collaborating and colliding with science
In the United States and other western countries, many common food practices and aversions often are based more on cultural preference than on scientific data.
“Pregnant women in the U.S. often microwave pre-cooked deli meat and tend to avoid sushi to reduce the risk of contracting listeriosis,” Placek said. “Although the risk of getting listeriosis might be low, the idea is that it’s better to be safe than sorry.”
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 really highly nutritious foods—foods they have access to and potentially beneficial to their babies,” she said.