Dietary Factors and Incidence of Hydatidiform Mole: An Ecological Study

The current ecological study aims to explore the association between dietary factors and hydatidiform mole (HM) incidence in Japan and China. HM incidence in Japan gradually declined from 1970s to 1990s, while the dietary structure also changed during the same period, mainly characterized by a decrease in the consumption of cereals and an increase in the consumption of meat, eggs, and dairy products. In China, HM incidence varied by regions, and it positively correlated with the per capita intake of rice, fish and shrimp, and animal fat, as well as the proportion of GDP of primary industry; and negatively correlated with the per capita intake of wheat flour, starch and sugar, protein, and iron, and the proportion of protein in the caloric nutrients and the proportion of nonagricultural population. In partial analysis, the correlations of HM incidence with rice, fish and shrimp, iron, and the proportion of protein in caloric nutrients remained significant. Meanwhile, alcoholic beverage consumption and the proportion of empty calories in caloric food were also found to be positively correlated with HM incidence, while phosphorus consumption was negatively correlated. Our results suggested that HM incidence could be influenced by dietary factors.