Elsevier

Social Science & Medicine

Volume 47, Issue 11, December 1998, Pages 1859-1871
Social Science & Medicine

Medicinal plants in Mexico: healers' consensus and cultural importance

https://doi.org/10.1016/S0277-9536(98)00181-6Get rights and content

Abstract

Medicinal plants are an important element of indigenous medical systems in Mexico. These resources are usually regarded as part of a culture's traditional knowledge. This study examines the use of medicinal plants in four indigenous groups of Mexican Indians, Maya, Nahua, Zapotec and – for comparative purposes – Mixe. With the first three the methodology was similar, making a direct comparison of the results possible. In these studies, the relative importance of a medicinal plant within a culture is documented using a quantitative method. For the analysis the uses were grouped into 9–10 categories of indigenous uses. This report compares these data and uses the concept of informant consensus originally developed by Trotter and Logan for analysis. This indicates how homogenous the ethnobotanical information is. Generally the factor is high for gastrointestinal illnesses and for culture bound syndromes. While the species used by the 3 indigenous groups vary, the data indicate that there exist well-defined criteria specific for each culture which lead to the selection of a plant as a medicine. A large number of species are used for gastrointestinal illnesses by two or more of the indigenous groups. At least in this case, the multiple transfer of species and their uses within Mexico seems to be an important reason for the widespread use of a species. Medicinal plants in other categories (e.g. skin diseases) are usually known only in one culture and seem to be part of its traditional knowledge.

Introduction

Most studies on medicinal plants focus on the role of these plants within one culture, i.e., one ethnic group. Little emphasis has been given to the comparison of medicinal plant species or other higher taxa (family, genera) in various cultures (cf. Heinrich, 1996; Moerman, 1996). Despite this neglect, a cross-cultural comparative approach has had a strong influence in anthropology (Harris, 1968) and especially in medical anthropology (e.g. Jordan, 1979; Lock, 1993). This study has therefore sought to examine the use of medicinal plants in four indigenous groups of Mexican Indians. With each group, representing a separate study, the methodology was identical except for the first study (Lowland Mixe), which was conducted prior to the other three. Work was conducted in collaboration with healers from the Isthmus Sierra Zapotecs, Oaxaca (Frei et al., 1998), the Yucatec Maya, Yucatán (Ankli et al., in press) and the Nahua of the Sierra de Zongolica, Veracruz (Weimann and Heinrich, 1997, Weimann and Heinrich, 1998). There are two alternatives when examining the use of medicinal plants: consensus and variation. Therefore an analysis of the plant usage must be performed in order to understand the patterns of use intra- and interculturally. Medicinal plants are not selected at random, but exhibit a considerable degree of patterning within one culture. The principal reason for this is empiricism; i.e. plants are selected and used in a consistent manner because of their culturally perceived effectiveness (Trotter and Logan, 1986; Trotter, 1981; Heinrich, 1998).

In recent years we have called attention to the lack of information on the relative importance of a medicinal plant (or other useful plant) within a culture and the need for comparing the use of plants interculturally (Heinrich et al., 1992; cf. Etkin, 1994; Moerman, 1996; for records of such data without an analysis see Amo, 1979; Alcorn, 1984; Aguilar et al., 1994). This paper specifically deals with medicinal plants, the relative role of the taxa used in the respective cultures and the relevance of these plants in the treatment of the diseases prevalent in the areas. A constructive method to obtain such information is the quantification of indigenous uses (Phillips, 1996; see also Phillips et al., 1994; Ngokwey, 1995). This is useful if the relative importance of each use is similar, as with medicinal plants used for different types of illnesses. This also forms the basis for studies in which the indigenous therapeutic claims are evaluated and in which some of the active constituents are isolated and their structures elucidated (Farnsworth, 1990; Kato et al., 1996; Bork et al., 1997).

Therefore the three ethnobotanical studies, which serve as the principal basis for this paper, employ similar methodologies (see also Section 2).

  • Specialists in medicinal plants (for example, healers, midwives, herbalists) were interviewed during 14–18 months of fieldwork and the use-reports of each informant for the plants were recorded.

  • The use of the plants were grouped into 9 or 10 categories (called categories of use). The principal categories are similar in all three studies: gastrointestinal, dermatological (mostly infections and subsequent inflammatory reactions), respiratory, gynaecological (and andrological) conditions. Since there are ethnomedical differences among the 3 ethnic groups, up to 6 additional categories were formed which pertain to only one or two of the groups. For example, the category for “poisonous animal bites and stings” applies only to the Maya; ophthalmological illnesses only to the Maya and Zapotecs; and culture-bound syndromes only to the Nahua and Zapotecs.

  • For each category the data were quantified by adding up the individual reports on the uses of each plant (see Ankli et al., in press; Frei et al., 1998; Weimann and Heinrich, 1997). They were then ranked according to the number of reports of use. We thus obtained information on the intracultural importance of a species.

Here the subsequent analysis is presented, which compares the relative importance of the taxa in the various categories of indigenous uses (the intercultural analysis). This comparative method allows not only the selection of indigenous medicinal plants for phytochemical and biological/pharmacological studies, but is also useful in determining the cultural importance of a particular plant as opposed to others in the same usage category. There have been several other approaches to establish quantitative criteria for the relative importance of plants (Friedman et al., 1986; Johns et al., 1990; Phillips, 1996; Berlin and Berlin, 1996). The one of Berlin and Berlin is of particular relevance to the discussion here. These authors used a largely similar approach, however, with the help of field assistants they interviewed the general population and thus recorded and evaluated an enormous set of positive responses: approximately 30,000 (Berlin and Berlin, 1996, 81–82). Their method requires a considerable investment in research funds and personnel. The method presented here is tailored to allow for the assessment of the relative cultural, medical, and consequently, the socio-economic importance of plants employed by medical specialists in an ethnic group. The earlier project on the Lowland Mixe is also based on a similar methodology, but the data were not quantified systematically. Instead, an estimation of the relative importance of the respective taxa was made (Heinrich, 1989).

Section snippets

General

All studies were conducted in Mexican Indian communities in the southern parts of Mexico (see Table 1 and Fig. 1). The Indian groups included belong to the Yucatec Maya, Lowland Mixe, Nahua of the Sierra de Zongolica and Sierra Isthmus Zapotec. Generally speaking, these regions are in the more marginal regions of Mexico. Emigration is frequent, especially with regard to the Zapotecs and Nahua. In all four groups subsistence agriculture is the economic basis, with corn being the main crop. Other

Results and discussion

The number of taxa recorded in the three studies (Zapotec, Maya, and Nahua) and the total number of use-reports (number of informants that report the use of this species) in these studies varies greatly among the three sites (see Table 1). This variation reflects the different amount of time that was required to built up a trusting relationship with key informants, the distance between the principal field location of the plants and the homes of the informants, as well as the number of key

Conclusion

If the role of medical ethnobotany is to be more than just compiling lists of plants used in indigenous medical systems, a standardised methodology is necessary to enable comparative evaluations. This paper discusses three ethnobotanical studies, in which a similar methodology was used and presents an intercultural comparison. The comparative approach is practical since both consensus and variation can be addressed. While the species used by the 3 indigenous groups vary, the data indicate that

Acknowledgements

This research project would not have been possible without the help of many people in the four regions, especially the midwives, healers, and specialists in medicinal plants. These persons are the original keepers of the ethnobotanical knowledge presented here. The botanical identification at the Herbario Nacional (MEXU) was performed in collaboration with numerous specialists of this institution, particularly O. Téllez V., R. Lira S., J. L. Villaseñor R., L. and R. Torres C. as well as Fr.

References (39)

  • Alcorn, J. B. (1984) Huastec Mayan Ethnobotany. University of Texas Press,...
  • Amo, R. S. del (1979) Plantas medicinales del Estado de Veracruz. Instituto Nacional de Investigaciones sobre Recursos...
  • Ankli, A., Sticher, O. and Heinrich, M. Medical ethnobotany of the Yucatec Maya: healers' consensus as a quantitative...
  • Berlin, B. and Berlin, E. A. (1996) Medical Ethnobiology of the Highland Maya of Chiapas, Mexico. Princeton University...
  • Brett, J. and Heinrich, M. (1998) Culture perception and the environment. Journal of Applied Botany 72(3/4),...
  • Etkin, N., ed. (1994) Eating on the Wild Side. The Pharmacologic, Ecologic and Social Implications of Using...
  • Farnsworth, N. R. (1990) The role of ethnopharmacology in drug development. Ciba Foundation Symposium, 154, pp. 2–11....
  • Frei, B., Sticher, O. and Heinrich, M. (1998) Medical ethnobotany of the Zapotecs of the Isthmus-Sierra (Oaxaca,...
  • Frei, B., Sticher, O., Viesca Treviño, C. and Heinrich, M. (1998) Plants as medicines and food: Zapotec criteria for...
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