From a socio-anthropological study focusing on maternal body weight perceptions and dietary practices towards infants living in Soweto (South Africa), we studied how lay sociocultural traits may lead to early childhood obesity. Most mothers tended to socially value and normalize fatness. This propensity led mothers, particularly older women at home, to adopt high-calorie feeding practices towards infants, although some mothers tended to question these lay norms. Further works must consider how lay (emic) sociocultural norms in African townships can contradict biomedical (etic) messages, conveying for the community thinness as the acceptable standard, and may expose infants to early obesity.