Chile (Capsicum spp.) as Food-Medicine Continuum in Multiethnic Mexico

Mexico is the center of origin and diversification of domesticated chile (Capsicum annuum L.). Chile is conceived and employed as both food and medicine in Mexico. In this context, the objective of this paper is to describe and analyze the cultural role of chile as food and as medicine for the body and soul in different cultures of Mexico. To write it, we relied on our own fieldwork and literature review. Our findings include a) the first matrix of uses of chile across 67 indigenous and Afrodescendants cultures within Mexican territory and b) the proposal of a new model of diversified uses of chile. Traditional knowledge, uses and management of chile as food and medicine form a continuum (i.e., are not separated into distinct categories). The intermingled uses of Capsicum are diversified, deeply rooted and far-reaching into the past. Most of the knowledge, uses and practices are shared throughout Mexico. On the other hand, there is knowledge and practices that only occur in local or regional cultural contexts. In order to fulfill food, medicinal or spiritual functions, native communities use wild/cultivated chile.


Introduction
Chile (common Spanish name derived from the Nahuatl language to be used here) is native to the Americas; however, it now flavors cuisines around the globe [1][2][3]. Mexico is considered the center of origin and diversity of domesticated Capsicum annuum L. chile with a continuous use of wild and domesticated varieties of at least 6000 years [4][5][6]. Thus, chile along with maize (Zea mays), beans (Phaseolus spp.) and squash (Cucurbita spp.) have coevolved with local groups even before the establishment of civilizations was recognized [7]. Currently, in Mexico there are about 60-70 indigenous groups that have safeguarded traditional/local environmental knowledge (TEK) related to the management, production and diversified use of natural resources including chile [8,9]. Two works framed in Mexico have described various uses of chile but were not exhaustive. Long-Solís [10] described various cultural aspects of chile at different times in the winding and intricate history of this region of the world. Data from Aguilar's doctoral dissertation [9] also describe other linguistic, historical, and archaeological data on the versatility and complexity of cultural patterns of chile production and use.
Due to the economic and food importance of chile around the world, hundreds of studies have been conducted on the nutraceutical importance of the spicy fruits when consumed directly in fresh bites or as part of a dish prepared with fresh or dried chile (without

Study Area
Mexico is the study area and it has a population with blurred ethnic boundaries [34] (see Figure 1), as other Latin American countries. In 2015, speakers of indigenous languages represent 6.5% of the total population in Mexican territory [35], but many people considered today as descend from indigenous people who lost their language [36,37]. They often share many cultural elements with the native communities of the same region, including agricultural and culinary traditions. The names of the native languages spoken were taken as a reference to delimit the modern cultures which descended from Mesoamerican intellectual traditions [38]. The list is based on the catalogue of indigenous languages of Mexico [39] that counts 67 linguistic groupings, used here as a unit of study, distributed in 364 linguistic variants (formerly linguistic groupings were considered as languages and their variants as dialects, but linguists have demonstrated that these last ones were actually languages). In addition, for the current analysis of the human-Capsicum relationship in Mexico, two groups of Afro-descendants were considered (one of Guerrero and Veracruz, and the Mascogo community of Coahuila).

Field Study
Araceli Aguilar has collected ethnobotanical data over 20 years, focusing on indigenous territories, following The Code of Ethics of the International Society of Ethnobiology. Datapoints of botanical samples gathered from fieldwork, national herbarium specimens and other datasets such as the CONABIO were utilized to draw the map of Figure 1. The map was already published (with graphical variation) in previous studies [20]. The others authors recovered ethnobotanical and ethnographic information regarding the genus Capsicum while focusing on the ethnoecology of chile, nurse plants, fowl, and Mexican indigenous people, such as the Chontales of Tabasco, the Zapotecs of Guelavía, and the Mixe of Guichicovi, Oaxaca (MAVD); working on Zapotec home gardens, ethnobotany of traditional agroforestry systems and traditional markets in Oaxaca (GIMM), and on food and agriculture with Mixtec people in Oaxaca and food studies around the country (EK).

Bibliographic Research
The authors reviewed articles of natural sciences, articles, books, and thesis of social sciences and cookbooks of the CONACULTA (cultural branch of Mexican federal government) collection called Cocina indígena y popular (Indigenous and popular cuisine). The search for natural sciences articles (original or review) was performed using the PubMed, Google Scholar, and Scopus electronic databases until March 2021. The main keywords used were: "Capsicum medicine"; "traditional use of Capsicum"; "Mesoamerica and Capsicum"; among others. All the included references were manually selected, reviewed, and added to the database in Filemaker by the authors.

Analysis of Cookbooks
In total, 77 cookbooks from the series Cocina indígena y popular and other Spanish written documents were reviewed. A database was constructed to determine the possible variety by inferring it with the common name. Recipes and culinary processes were registered as well. Annotations about the languages were important to determine the cultural context of the cookbook.

Classification of Illnesses
Diseases or symptoms associated with potential modern diseases were classified according to the 2021 WHO system, the ICD-11 version 09-2020 (https://icd.who.int/ browse11/l-m/en (accessed on 1 March 2021)), into 12 categories: (1) infectious or parasitic diseases, (2) mental, behavioural, or neurodevelopmental disorders, (3) diseases of the nervous system; (4) diseases of the visual system; (5) diseases of the ear or mastoid process; (6) diseases of the respiratory system; (7) diseases of the digestive system, (8) diseases of the skin; (9) diseases of the musculoskeletal system or connective tissue, (10) diseases of the genitourinary system, (11) pregnancy, childbirth or puerperium and (12) poisoning. This classification is an interpretation/translation of the authors of this paper and is not based on an emic view of the local medicine of each culture. Medicine for the soul area: to describe cultural-bound syndromes that Western mental health professionals and scientists fail to validate as "real illnesses" [40].

Results
Chile functions as a multifocal symbol operating intimately on many levels of people's lives. Plant use is an integral part of the mental and physical life of people who live in direct contact with their natural resources. This is a resilient factor among indigenous communities worldwide. Like another Latin American countries, Mexico has a mixed population with blurred ethnic boundaries [34]. Presently speakers of indigenous languages represent 6% of the population [41], but many people considered today as mestizos descend from indigenous people who lost their language [36,37]; they often share many cultural elements, including agricultural and culinary traditions, with the native communities of the same region. Chile are always part of all of them since it is a crop that has intertwined its history with the history of the cultures that domesticated it [38].
The analysis of 77 cookbooks edited by CONACULTA gave some clues as to which chile are depicted on modern written documents (Table 1). Only six cookbooks were bilingual; Nahuatl [42], Tarahumara [43], Mayo [44], Yaqui [44], Purepecha [45], Totonac [46], Tepehuan [47] and also included common names for chile on each languages. In total, 32 out of 77 have some common names for ingredients in local languages but not terms referring to chile were included. Culinary processes mentioned for cooking or using chile were: deveined, roasted, boiled, grilled, ground, molcajeteado (crushed in a stone such as mortar), chopped, sieved, crushed, seeded, cut into small pieces, washed, blended, stuffed, stuffed, fried, cooked, shredded, scrambled, burned, soaked, ground, parboiled, strained, soaked, browned in oil, ground in metate, sprinkled, filleted, finely chopped, stewed, seasoned, sautéed, mashed, chopped, sliced. Seri Seri [104] No language affiliation Mascogos [105] No language affiliation Afrodescendants [106,107] Out of 3641 records, 561 chile with no specific name, 105 wild chile, and 2975 domesticated chile were used. Three main groups of chile were commonly used in recipes all over Mexico. The grouping was made by the fresh and dry state of the same variety (except for guajillo) (1) complex Poblano/Ancho/Color (550 records); (2) Guajillo (445 records) and (3) Jalapeño/Chipotle (337 records), common names for fresh chile of this group are: Jalapeño, Cuaresmeño, Gordo and Huauchinango, common names for dry chile are: Chipotle, Mora and Morita. Another classification was the rarely mentioned names (44 records with less than 3 records), 89 chile are C. chinense and C. pubescens versus 2535 corresponding mainly to domesticated varieties of C. annuum. The variability of the amount of spice consumed in Mexico's culinary mosaic is impossible to describe by scientific standards. Some studies have made metabolomics studies that give some hints as to the biochemical variants expressed in the flavor, heat, and odor of chile [108] but tests have yet to be conducted on the complex culinary dishes of multi-ethnic Mexico.

Chile as Food
Chile is ubiquitous in all Mexican food. According to Elisabeth Rozin [109], it is its "flavoring principle". However, it is much more than a flavor. For Mexican people, most foods cannot be eaten without chile. Not only would it be bland, but also it would not be a balanced meal. Most Mexicans conceive that hot and cold principles rule food and body health. According to cultures and regions, different qualities may be attributed to foodstuffs, but they are usually the same for the staples: corn is considered as warm, beans as cold and chile is hot. "Cold" food is not good for the body, a meal must tend toward "warm" food, without being too hot, except in case of a "cold" disease, when food must heat up the body [110].
For centuries, Mexican peasants have been basing their diet on boiled beans and corn tortillas, with chile. For city dwellers, corn and beans may not be the basis of their diet, if they consume more meat, for instance, but are at least the side dish. Corn and beans balance each other, beans cannot be eaten alone, and usually are cooked with chile, as "cold" food is supposed to be heavy to digest. Then raw chile or a chile sauce is served on the table, and each eater adds it to the plate according to the individual taste. Most dishes are cooked together with raw or dry chile (meat, vegetables, etc) or in elaborated chile sauces (mole, adobo, etc). Chile is added to industrial food, such as tortilla chips, to sweets, even when designed for children. Corn on the cob and sliced fruits (such as mango) eaten as snacks, and often sold on the street, are served with lemon and chile powder.
Without chile, the body balance would be in danger. However, if the person is sick, chile is not recommended [102]. Many people we interviewed declared that they were strong or resistant thanks to chile. This was particularly true in rural areas, where people compared themselves to city dwellers, or to "gringos", whom they judged weaker. Children get used to chile from their earliest age, in their mother's womb, through their mother's milk, from the smells of their family's kitchen. Chile is progressively introduced in their food so that at an early age (some beginning at the age of four), children like to eat chile [111].

Chile as Medicine for the Body
Due to the effectiveness of using chile to heal, dozens of modern scientific studies have currently been carried out to recognize its therapeutic action [112][113][114][115] and that have indirectly validated the ancestral and traditional uses. Here we depicted a brief description: (1) Certain infectious or parasitic diseases: antibacterial and antimicrobial [96,116]; the Pimas of Sonora use it as antibacterial [96]; Nematicide [10,117]: the Pimas of Sonora use it as a nematicide [96]; Fever: in Santo Domingo Petapa and Santa María Petapa, the Zapotecs of the Isthmus to relieve fever [61]; the korí chókame (black chile) of the Raramuris is used to prepare a tea to relieve fever [97]; in Santo Domingo Petapa and Santa María Petapa, the Zapotecs of the Isthmus use chile to relieve fever [61]. (2) Mental, behavioral, or neurodevelopmental disorders: the Raramuris and Mestizos use isíburi (plant mixture with chile) to treat hangovers and fever [97]. Austin [120] says that the Nahua cured ear ulcers with warm drops of coyoxóchitl with chile; the Raramuris use it to treat ear pain [97]; mestizos from Sonora use the oil of chiltepín (C. annuum var. glabriusculum) to cure ear pain [121]. (6) Diseases of the respiratory system [46,69,113,120]: Nahua to treat cough in Tlanchinol, Hidalgo [122]; mestizos in the State of Querétaro cure certain pulmonary ailments and fevers by smoking dried chile to cause sweating and coughing [119]; Sahagún quoted by López Austin [120] says that the Nahua drank water from the root of the tlacopópotl, and lime water with chile and a decoction of iztáuhyatl to cure coughs and expel phlegm. Mestizos from Sonora eat a lot of chiltepín (C. annuum var. glabriusculum) to avoid the flu and smoke it with tobacco to remove the cough [121]. (7) Diseases of the digestive system including teeth conditions [69,113,120,123]; mestizos in the State of Querétaro use it to prevent constipation and gastritis [119]; Sahagún quoted by López Austin [120] says that the Nahua cured constipation by administering through the anus a suppository made with soot and a little saltpeter, kneaded with rubber filled with chile, made into a ball and inserted from behind, and to tartar diarrhea they drank chía (Salvia hispanica) atole (maize based drink) mixed with chía totopos (grilled tortillas) and sprinkled with chile; Mestizos from Sonora use chiltepín to cure ulcers, gastritis, and hemorrhoids [121]; the BDMTM mentions that it is used as an antidiarrheal, carminative, eupeptic [118]; Lacandon Maya uses chile to soothe toothache and inflamed gums [124]. (8) Diseases of the skin [113]: mestizos in the State of Querétaro apply an patch of ground piquín chile to areas of the skin affected with erysipelas or festering so that the wound does not become infected and that it helps with pain [119]; mestizos in Sonora use chiltepín (C. annuum var. glabriusculum) to heal wounds [121]; the BDMTM mentions that in Veracruz and Oaxaca it is used to treat chincual de criatura (cultural illness), erysipelas and wounds, as well as being used as an antiseptic [118]; Tenek of San Luis Potosí use it to cure skin problems [29]; the Zapotecs of San Juan Guelavía use it roasted and dried to remove pimples from the face [23]; in the Tzotzil of Zinacantán, Chiapas [74]. (9) Diseases of the musculoskeletal system or connective tissue: the BDMTM mentions that it is used as antirheumatic [118]: the Raramuris use chiltepín in poultice to relieve arthritic pain in the hands [97]; to cure broken bones: Otomí bonesetters use to massage the rib cage while the patient blows into a bottle to reset broken ribs. Then they put a cataplasm of sacasil tuber ground with cumin (Cuminum cyminum), cayenne chile (Capsicum sp.), and cloves (Eugenia caryophyllus) over the lesion [125]. (10) Diseases of the genito-urinary system; [69,113,120]. (11) Pregnancy, childbirth, or puerperium help to mitigate labor pain and promotes delivery [69]. (12) Poisoning. Mestizos from Sonora use chiltepín (C. annuum var. glabriusculum) with tallow for tarantula bites [121].

Chile as Medicine for the Soul
The use of herbal medicines, and complementary and alternative medicine, is increasing globally. There is an emphasis on a holistic approach, consistent with definition of health of the World Health Organization (WHO). Health is understood as being the combination of physical, mental, social, and spiritual well-being and life as being a union of body, mind, and soul. In this section, we will describe chile as medicine for the soul. The concept of the soul is not universal, nor is it found in all cultures. In Mexico, several native terms are translated as soul, such as tonalli among the Nahua [126] or pixan among the Maya [127]. According to the Nahua, the fetus receives both a soul and a heart during the gestation process. The soul is given by the Sun-God and is therefore considered "warm"; based in the heart, it endows the infant with life and the capacity for movement and growth [128]. The soul or spirit of a person can be affected by various natural and supernatural agents, causing psychosocial and somatic imbalance. The sick person then turns to traditional medicine to regain balance, health, and well-being. Many traditional cultures in Mexico use diverse species of plants (and a few animals) to cure people of the evil eye (mal de ojo in Spanish). Generally, it can be characterized as the personal emanation of a force that arises involuntarily due to a strong desire and that harms the desired being. The evil eye is a recognized cause of health care in Mexico, especially by rural inhabitants and traditional healers. This condition is considered a culture-bound syndrome in which there is a state of restlessness characterized by anxiety, depression, insomnia, and loss of appetite [129]. Children are the main population affected by the evil eye. Chile is used in various ways to prevent and cure the evil eye in several ethnic cultures of Mexico; for example, the Zoques of Chiapas [130], the Zapotecs of Oaxaca [23], five ethnic groups of Puebla [128], the Huastecs of Veracruz [131], the peasants of Querétaro [119], and the Guarijío and Mayo of Sonora [121]. Other ailments related to the soul and in which chile is used as medicine are: "dead people's evil wind" (mal aire de muerto in Spanish), a bad entity that comes from people who just died, registered in Oaxaca with Mixes and Mixtecs [22,132]; evil supernaturals, fright, and witchcraft among Zapotecs of Oaxaca [23,133].

A Model of Human Management of Chile in Mexico
The model of human management of chile proposed here is shown as a continuum that goes from wild to domesticate with blur limits (Figure 2). As an addition to this model, the native species utilized are wild and domesticates of C. annuum and C. frutescens.

Conclusions
This work shows that Mexico's ethnic cultures conceive, use and manage chile as a food-medicine continuum and can possibly be explained because it is a fruit that, similar to corn, has a deep symbolic meaning in Mesoamerican and Arid American cultures.
The use of chile in food is common to the whole territory providing nutrients to the Mexicans who consume them [25]. The present study shows data confirming this fact. However, regional studies that connect the studies of secondary metabolites of local cultivars with the preferences of the uses of each culture are needed to achieve a better understanding of the patterns of human selection on a plastic crop of the Solanaceae family. This study also concluded that medicinal uses for the body and soul have very restricted use in current times when compared to the presence of chile as food.
We need to further test the local concepts of illness (imbalance) and health (equilibrium) using chile as a theoretical axis to approach descendants of the Mesoamerican intellectual traditions within the multiethnic territory. Chile has been used in different cultural spaces at different times to cure various diseases that were classified here in 12 categories. Scientific results validated many of the ancient uses of chile as medicine (see Table 1 and section chile as medicine for the body). Some questions to be pursued for future studies are (1) have medicinal uses been lost at different scales (community, language/culture, or nationwide)? (2) do we have knowledge of the ingredients, preparation processes, and utensils to prepare chile as a medicine for a particular ailment? There is a wide range of uses where the spicy fruit is consumed and putatively act as a protector element, medicine, and/or food. A more holistic way of presenting natural resources within the academic world is increasing in popularity [134] recognizing the need to present a more "real" picture of how natural resources are perceived and utilized.

Conclusions
This work shows that Mexico's ethnic cultures conceive, use and manage chile as a food-medicine continuum and can possibly be explained because it is a fruit that, similar to corn, has a deep symbolic meaning in Mesoamerican and Arid American cultures.
The use of chile in food is common to the whole territory providing nutrients to the Mexicans who consume them [25]. The present study shows data confirming this fact. However, regional studies that connect the studies of secondary metabolites of local cultivars with the preferences of the uses of each culture are needed to achieve a better understanding of the patterns of human selection on a plastic crop of the Solanaceae family. This study also concluded that medicinal uses for the body and soul have very restricted use in current times when compared to the presence of chile as food.
We need to further test the local concepts of illness (imbalance) and health (equilibrium) using chile as a theoretical axis to approach descendants of the Mesoamerican intellectual traditions within the multiethnic territory. Chile has been used in different cultural spaces at different times to cure various diseases that were classified here in 12 categories. Scientific results validated many of the ancient uses of chile as medicine (see Table 1 and section chile as medicine for the body). Some questions to be pursued for future studies are (1) have medicinal uses been lost at different scales (community, language/culture, or nationwide)? (2) do we have knowledge of the ingredients, preparation processes, and utensils to prepare chile as a medicine for a particular ailment?
Although there are many studies that validate the efficacy of chile in curing diseases such as cancer [135]. Other healing properties have been attributed to chile, as documented in this study, particularly the properties to cure culturally affiliated diseases whose biochemical foundation is unclear or it might be healing in other forms. Eleven ethnic groups of Chiapas, Oaxaca, Puebla, Veracruz, Querétaro, and Sonora use chile to prevent and cure the evil eye. In Oaxaca, Mixes, Mixtecs, and Zapotecs use chile against evil beings, fright, and witchcraft. Therefore, we should initiate systematic studies in Mesoamerican cultural contexts to acknowledge more complex illnesses that have been made invisible for the global academic world.
There are shared uses, practices, and knowledge throughout the Mexican territory such as the spicy fruits being used as condiments and vegetables to prepare food. On the other hand, specific uses within the medicinal (body and soul) categories are found in local contexts unique to a particular indigenous culture that are not repeated in the rest of the country. It may be the reason why there is a high diversity of chile in the form of cultivars of C. annuum var. annuum that are the result of locally selected unique morphotypes.
Further research is needed to fill the gaps in local and indigenous knowledge by training local ethno-scientists [136] to carry out participatory research with a dual purpose: to generate academic knowledge and to restitute that knowledge to the communities where biodiversity is being conserved [137]. This is particularly relevant in one of the most megadiverse countries of the world, Mexico.