Plants and Indigenous Medicine and Diet

Biobehavioral Approaches

Nina L. Etkin

• Publisher: Routledge
• Year: 2019
• eBook ISBN:
  9781135882778
• Print ISBN:
  9780913178027
• Subtopic: Botany

The aim of this volume is to promote a bio-behavioral focus for indigenous plant research.

PART ONE
The Importance of Multidisciplinary Approaches to Plant Use

CHAPTER 1
Multidisciplinary Perspectives in the Interpretation of Plants Used in Indigenous Medicine and Diet

Nina L. Etkin
Department of Anthropology
University of Minnesota
Minneapolis, Minnesota

Introduction

Investigations of medicinal and dietary plants play an important role in elucidating the dynamic interrelationships between the quality of human health and features of the physical and sociocultural environment. Our understanding of such human-plant interactions is informed by the research contributions of diverse disciplines which can be most constructively articulated as multi-disciplinary approaches in the study of ethnobotany and ethnopharmacology. Ideally, such multidisciplinary studies would combine the perspectives of: ethno- and scientific-botanical identification and classification; pharmacologic characterization of plant constituents and their activities; Western biomedical and nutritional research concerned with the effects that indigenous medicines and dietaries have on human health; and behavioral investigations which interpret plant knowledge and use as part of the aggregate environmental and sociocultural contexts within which human-plant interactions are integrated. However, although many researchers have emphasized the merits of such comprehensive investigations of ethnomedical efficacy (e.g., Bernardi 1980; Bruhn and Helmstedt 1981; Etkin 1979a, [n.d.]; Lewis and Elvin-Lewis 1977; Rivier and Bruhn 1979; WHO 1978), there have been relatively few multidisciplinary or concerted interdisciplinary studies which effectively articulate the biomedical and behavioral dimensions of plant use.

For example, while many anthropologists and other social scientists propose to place their observations within a broad biobehavioral framework, their interpretations more typically reflect a perspective that views plants rather narrowly as cultural objects. Thus, considerable research attention has been devoted to the relationship between medical cosmologies and perceptions of the biological universe, culturally patterned selections of plants for foods and medicines, and the psychosocially integrative dimensions of ethnomedical and dietary behaviors. On the other hand, botanists and pharmacologists have been more interested in biological studies which are frequently devoid of cultural and other contextual data. Collectively, then, the literature of ethnobotany and ethnopharmacology is largely botanically uninformed or anthropologically naive, and at present a multidisciplinary understanding of plant use is more a conceptual ideal than an operational reality.

Nonetheless, the importance of such an approach is well recognized; and there is a growing corpus of evidence which attests to the potential utility of its application. This chapter selectively reviews the recent literature to discern several conceptual and methodological themes that underscore the merits of multidisciplinary approaches in the interpretation of plant use. Part I discusses the manner in which medical and dietary ideologies influence plant selection, preparation, and use and how such behaviors may modify or be otherwise related to the biological properties of these plants. Part II reviews investigations that draw on such observations to discuss various approaches used in biomedical evaluations of ethnomedical and dietary behaviors.

I. Behavioral Dimensions of Indigenous Plant Utilization

A. Ideology and Patterns of Plant Selection and Use

In view of the importance of the sociocultural contexts in which plant use occurs, much attention has been directed toward understanding how indigenous populations structure their knowledge of the biological universe. Specific questions relevant to this discussion center about how and why people select particular plants for medicinal, dietary, or other applications and ultimately what influences such behavior may have on human health and disease. There is ample evidence to suggest that the selection of specific plants is not solely a function of availability (e.g., Moerman 1979a; But et al. 1980) and that, instead, specific biological and behavioral variables become important influences on plant utilization in any given setting.

These investigations are informed in part by anthropological linguistic descriptions and analyses of ethnomedical, ethnobotanical, and related classifica-tory systems. For example, some of these studies have attempted to relate lexical and taxonomic elaboration to the cultural significance of plants, foods, medicines, etc. (e.g., Berlin et al. 1974). Although the utility of these ethnoscientific interpretations has recently been the subject of criticism and reevaluation (e.g., Alcorn 1981; Hays 1982), they provide some foundation for discerning cognitive categories relevant for understanding the various ways in which plants are perceived and used.

The specific cultural meanings and values ascribed to food plants will determine their patterns of use and/or avoidance in any given population (e.g., Back 1976; de Garine 1976; Ferro-Luzzi 1977; Hodgson 1977; Simoons 1978). Similarly, the use of plants in a particular medical system is consistent with the prevailing medical cosmology, including concepts of illness, disease etiology, expected sequelae of preventive and therapeutic measures, and the like (e.g., Foster and Anderson 1978; Grollig and Haley 1976; Hill and Mathews 1981; Landy 1977; Leslie 1976; Logan and Hunt 1978; Moerman 1974; Moore et al. 1980; Romanucci-Ross et al. 1983).

In many cultures patterns of plant utilization are organized by various formulations of the humoral theory of disease in which etiologies are ascribed to imbalances and treatments are directed toward restoring harmony. Of these, hot-cold binary opposition is a familiar idiom throughout Mexico and Latin America and in parts of Africa, Asia, and Europe. Similarly, a sweet-bitter opposition is recognized among populations in the Southern U.S. Humoral balance also is characteristic of traditional Ayurvedic (tridosha), Chinese (yin-yang), Greek, and other medical systems. In other cases plant selection may be patterned in accordance with the belief that some tangible attributes of the plant serve as signs to indicate its utility (Doctrine of Signatures). For example, in Belize, headache is treated with stinging nettles (Urtica spp.), while burns are treated with hot peppers (Capsicum spp.) (Arnason et al. 1980). Other common cross-cultural examples include the use of plants which exude milk-like latex (e.g., Euphorbia spp.) as galactagogues (e.g., Camazine and Bye 1980; Sofowora 1982). Many other examples might be cited, including those in which the symbols relate not only to superficial qualities but also to more elaborate reflections of indigenous cosmologies (e.g., Herrick 1983; Ingham 1970; Janzen 1978; Johns [this volume]).

The selection of medicinal, dietary, and other plants also may be guided by the anticipation of certain tangible physiologic reactions which are perceived as proximate effects in a processual ordering of treatments and/or the requisite specific therapy for a particular disease. In many ethnomedical systems the expectations of treatment include perceptible evidence that disease entities or substances leave the body. For example, the widespread use of Pilocarpus jaborandi in South American ethnomedicine has been interpreted to reflect the sudorific and sialogogic properties of this plant (Holmstedt et al. 1979). In Zuni (New Mexico) and Hausa (Nigeria) indigenous medicine, evidence of disease egress is particularly important in the treatment of gastrointestinal disorders (Camazine and Bye 1980; Etkin and Ross 1982), and the preferred plant medicines include those intended to exert diuretic, emetic, sudorific, and laxative activity. In addition to these proximate effects symptom remission ultimately is required, and costive, emollient, and antispasmodic action is anticipated upon completion of the full treatment process. Similarly, as reflections of Mexican American medical ideologies, such practices as leaving diarrhea unchecked and allowing ulcers to drain confirm the belief that health is restored through the elimination of disease substances (Kay 1977).

Thus, the selection of plants for medicinal, dietary, and other uses involves a complex integration of meaning, intent, and expectations which are variably articulated according to context and which may differ appreciably cross-culturally. All these considerations apply as well to the details of preparation, combination, dosage, and application, as illustrated below.

B. Biobehavioral Dimensions of Indigenous Plant Preparations

A fundamental concept in the ideologies of many ethnomedical systems and dietaries is that therapeutic and other benefits are afforded through plant mixtures in which whole plants or plant parts are prepared and/or consumed in combination or in sequence. Thus, physiologic (as well as symbolic) meaning is dependent upon qualities inherent in the composite nature of these mixtures. Pharmacologic investigations have paid particularly little attention to such aspects of plant utilization. This is partly due to the problems involved in ascribing effects to one of many constituents of a single plant, which are further confounded when the constituents of several plants must be considered. These difficulties notwithstanding, composite mixtures merit closer scrutiny in light of the potential synergistic, additive, and/or antagonistic effects which may accrue when different constituents interact.

Pharmacologic investigations of indigenous plants which employ variously purified extracts or synthetic analogues ignore the possibility that some of the ostensibly “inert” constituents of these plants may have important effects. For example, the administration of pharmaceutical digitalis in Western biomedicine necessitates temporary interruptions of therapy to avoid the accumulation of this drug. By contrast the ethnomedical use of the whole Digitalis plant may take advantage of other constituents in this plant which prevent digitalis accumulation (Scarpa 1981). Similarly enhanced activity in composite medicinal preparations is observed in the South American hallucinogen, ayahuasca—a plant mixture comprised principally of Banisieriopsis caapi and B. inebrians, the constituents of which amplify the hallucinogenic tryptamines of admixed plants such as Psychotria spp. and Banisieriopsis rusbyana (Schultes and Hofmann 1979).

The observation that a large number of indigenous pharmacopoeias include species that are used in many composite medicines has been variously interpreted to reflect the use of these plants as mechanical and/or symbolic adjuvants, vehicles, or facilitators of other ingredients. And because these plants are used in the treatment of a broad range of disorders, any benefit attributed to plant mixtures is usually presumed to be due to the activity of other components. An interesting exception to such interpretations is the research of Atal et al. (1981) on the Ayurvedic medicine trikatu. This compound of Piper longum, P. nigr...

Table of contents

• Cover
• Half Title
• Title
• Copyright
• Contributors to This Volume
• Dedication
• CONTENTS
• Preface
• PART ONE THE IMPORTANCE OF MULTIDISCIPLINARY APPROACHES TO PLANT USE
• PART TWO CRITERIA USED IN THE SELECTION OF MEDICINAL PLANTS
• PART THREE PLANTS IN MEDICINAL AND DIETARY CONTEXTS
• PART FOUR MEDICAL PANACEAS AND MISUNDERSTOOD PLANTS
• Index