The present study investigated Guarani village interviewees’ diet changes over time, their perceptions about the changes and the effects of these changes on their health.

The study employed qualitative methods with a sample of Guarani Indians selected by snowball sampling. Ethnographic methods and techniques included field diaries, informal and unstructured interviews and participant observation.

The Tenondé Porã Guarani village is located in the district of Parelheiros, São Paulo, Brazil. Interviews were conducted from July 2008 to December 2009.

Fifteen Guarani Indians, males and females in age categories ranging from youths to elders, took part in the study.

The interviewees reported changes in how food was obtained, the occurrence of food substitutions and food species abandonment, recipe changes and the introduction of new foods. Some ritual use of plants was maintained. Disease frequency was found to increase because of this change and a lack of obedience to Nhanderu (the Guarani God). A lack of space for daily traditional activities (e.g. farming, hunting) was found to result in sedentary lifestyles.

The village location was a key factor in the Guarani diet change, although some rituals related to available plants were preserved.