If you’ve never heard of it, favism, or favismo in Italian, sounds suspiciously like a food legend or superstition. In fact, favism is a real hereditary disease resulting from a defect of the gene that regulates glucose-6-phosphate, defined by Merriam-Webster as ‘a condition especially of males of Mediterranean descent that is marked by the development of hemolytic anemia upon consumption of broad beans or inhalation of broad bean pollen and is caused by a usually inherited deficiency of glucose-6-phosphate.’
Most people live with favism symptom-free, yet when it does manifest, the disease can lead to, among other things, serious kidney problems. The term favism is a bit of a misnomer, since not all people affected with glucose-6-phosphate dehydrogenase deficiency—the technical name, commonly abbreviated as G6PD deficiency—will manifest symptoms after consuming fava beans or being exposed to pollens. Women can carry this genetic defect and pass it to male offspring.
About 400 million people worldwide have G6PD deficiency, predominantly in Africa, Southeast Asia, and the Mediterranean. Rates of favism are high in Sardinia, also known for its high rate of centenarians. Interestingly, a recent study by the University of Sassari suggests a connection between G6PD deficiency and longevity: scientists observed that the lack of the G6PD enzyme was twice as common in Sardinian centenarians, leading them to theorize a relationship between a so-called ‘longevity gene’ and the genetic defect that causes this particular deficiency. (Sardinia is one of the world’s five blue zones—areas with the highest documented rates of longevity—along with Costa Rica; Okinawa, Japan; the Greek island Ikaría; and Loma Linda, California.) So perhaps there’s a silver lining to favism.
For the rest of us, fava beans are a tasty and versatile legume, rich in protein, fiber, vitamins, and minerals*. Some of the many ways to eat fava beans are raw with pecorino cheese, cooked lightly and tossed with pasta and pecorino (pictured above), or processed into a pesto-like paste to spread on crostini with other vegetables, cheese, or grilled prawns, as pictured here:
*Fava beans contain isoflavones, which are considered both good (as antioxidants) and potentially bad (as phytoestrogens). Whether isoflavones should be moderated in the diet is debatable, as some clinical studies have shown these substances to have beneficial therapeutic and disease prevention qualities, while others suggest they should be avoided for the same reasons one would avoid consuming any synthetic hormone. Fava beans are included, for instance, in The New Mayo Clinic Cookbook as a ‘healthy’ food, while the Mayo Clinic website also notes: ‘Studies on phytoestrogens—whether from food or supplements—haven’t shown a convincing and consistent effect on hot flashes or other menopausal symptoms. Some experts speculate that phytoestrogens could increase the risk of breast cancer or interfere with the effectiveness of tamoxifen in women with breast cancer.’ Most current discussions of the potential risks associated with phytoestrogens center on soybeans and derivative products, such as milk and oils.