Abstract
Food cravings are common during pregnancy, but in addition is craving and ingestion of non-food substances such as soil, and soft stones, termed 'pica'. A common form of pica is the ingestion of soil (geophagia). This study aimed at determining the chemical composition of kaolin and bentonite cla and ascertaining their consumption prevalence among women in Calabar and Onitsha – southern Nigeria. The edible clays collected were ground to fine powder and sieved for analysis. Proximate analysis was carried out using AOAC standard methods. For the determination of macro minerals, heavy metals and anti-nutrients, the samples were digested and analysed using Atomic Absorption Spectrophotometry. To assess the consumption prevalence, a structured questionnaire was designed, content-validated, pre-tested and used. Data was analysed using Microsoft Excel and Statistical Package for Social Sciences (SPSS).The results of the proximate analysis showed a high content of ash (85%) in both samples. Kaolin had significantly (P<0.05) higher content of sodium and magnesium while calcium was significantly (P<0.05) higher in bentonite. For the heavy metals, kaolin had significantly (P<0.05) higher content of lead, arsenic and aluminium. Among the respondents, about 75% admitted to consuming both clays (during and after pregnancy). The two edible clays are commonly consumed by women, irrespective of age and educational status. Both kaolin and bentonite clays contained appreciable quantities of important micronutrients but also contained some anti-nutrients and heavy metals, hence they should be consumed with caution, especially during pregnancy.