Premastication, pre-chewing, or kiss feeding is the act of chewing food for the purpose of physically breaking it down in order to feed another that is incapable of masticating the food by themselves. This is often done by the mother or relatives of a baby to produce baby food capable of being consumed by the child during the weaning process. The chewed food in the form of a bolus is transferred from the mouth of one individual to another, either directly mouth-to-mouth, via utensils, hands, or is further cooked or processed prior to feeding.
The behaviour was common throughout human history and societies and observed in non-human animals. While premastication is less common in present-day Western societies it was commonly practiced, and is still done in more traditional cultures. Although the health benefits of premastication are still being actively studied, the practice appears to confer certain nutritional and immunological benefits to the infant, provided that the caretaker is in good health and not infected by pathogens.
Premastication and mouth-to-mouth feeding in humans is postulated to have evolved from the regurgitation of food from parent to offspring or male to female (courtship feeding) and has been observed in numerous mammals and animals of other species. For instance, food begging behaviour observed in young wolves, wild dogs and certain gulls species, which involves the young approaching the beak or mouth of the adult with their own whereupon gaping their mouths or nuzzling, the adult would regurgitate portions of food to feed the young. However, in the aforementioned animals, this nuzzling behaviour and other types of mouth-to-mouth contact are also used for bonding, socialization, and courtship.
Young orangutans also beg for food by such contact and accordingly their caretakers regurgitate to feed them. Indeed, behaviours of mouth to mouth feeding of premasticated food and ritualized mouth to mouth contact for bonding has been observed in anthropoid great apes such as gorillas, orangutans, and chimpanzees. All of this supports the idea that human behaviours of kissing and feeding of premastication foods, either directly or indirectly from the mouth, have their behavioural roots in higher animals and ancestral great apes.
Human kiss precursor
In all human cultures premastication/kiss-feeding or kissing between mother and infant has been observed in all with kissing believed to be a socially ritualized form of feeding premasticated food. There is high similarity in the execution of kiss-feeding and human kisses (e.g. French kiss); in the former, the tongue is used to push food from mother to child with the child receiving both the mother's food and tongue in sucking movements, and the latter simply forgoes the premasticated food. In fact, observations across various species and cultures confirms that the act of kissing and premastication have most likely evolved from the similar relationship-based feeding behaviours.
History and culture
Written records of premastication have been found in Ancient Egypt, though the practice likely extends back into prehistoric times to non-human ancestors. For instance, in the Ancient Egyptian Ebers medical papyrus, a mother was instructed to give a medical remedy to a child through premastication. In the fifth century A.D. Roman culture, premastication of infants' food by caretakers was also common, though the lack of sanitation along with the practice contributed to infant mortality. Infants in Medieval Europe were fed an assortment of mashed, premasticated food or bread softened with liquids.
Due to attitudes in Western medicine in the 1940s and 1950s, Native American and Fijian cultures and societies were strongly dissuaded from premastication due to concerns about the hygiene of the practice. However, the lack of knowledge regarding premastication and its prohibition by missionaries and doctors instead caused severe anemia in the infants of the population, or resulted in malnourished infants and children deprived of nourishment.
Although less prevalent in modern post-industrial Western societies, the offering of premasticated foods to infants is found in many traditional cultures and offers their infants numerous benefits. In North America, premastication is still commonly used by Black and Hispanic mothers, and commonly used by women of Inuit and Aleut peoples.
In many human cultures, the act of premastication and direct mouth-to-mouth feeding is linked with the showing of affection, known as kiss feeding. In the Manus cultures of the Admiralty Islands, the act of premastication has been used by a women to remind children and descendants of their obligations to her. Some human cultures such as the people of Papua New Guinea in fact use mouth to mouth contact primarily for feeding premasticated food, with sexual kissing only observed after the arrival of Europeans. This form of feeding is believed to have evolved into the modern human acts of kissing and French kissing.
Many Western societies have strong aversions toward premastication, which have been compared to their similar criticisms and aversion towards breastfeeding in previous generations for similar rationale, with the same societies finding breastfeeding to be a disagreeable practice performed only by the uneducated lower classes or untempered foreign cultures. For instance, in the late 1800s the medical community of Texas was embroiled in a debate on premastication, with those supporting the practice arguing its benefits and those against it stating that it is "filthy and repulsive and... barbaric".
The act of premastication is commonly found in all human societies and populations, although it is less prevalent in some than others. The evolution and selective advantage of premastication behaviours is that it supplements the infant diet of breast milk by providing access to more macro- and micro-nutrients. Although disease can be transmitted through saliva in the pre-chewed foods, the benefits conferred outweighed any risks of the practice during the evolution of human behaviour. Furthermore, discouraging premastication as prevention to disease transmittion may prove as disastrous an infant public health policy as when infants breastfeeding was discouraged in the late 1980s and early 1990s. In the end, the potential benefits and pitfalls of this practice greatly depend on the dietary and medical circumstances of the provider and child. The true scope of the benefits of premastication and its prevalences in differenct societies is still under active research, though there appears to be some consensus on the nutritional benefits of the practice.
- Holmes, Wendy (2007), "Influences on maternal and child nutrition in the highlands of the northern Lao PDR", Asia Pac J Clin Nutr, 16 (3): 537–545, PMID 17704036
- Zhang, Yuanyuan (May 2007), "The role of pre-mastication in the evolution of complementary feeding strategies: a bio-cultural analysis" (PDF), Cornell University College of Agriculture and Life Sciences Honors Theses
- Pelto, Greta; Zhang, Yuanyuan; Habicht, Jean-Pierre (January 2010), "Premastication: the second arm of infant and young child feeding for health and survival?", Journal of Maternal and Child Nutrition, Blackwell Publishing Ltd, 6 (1): 4–18, doi:10.1111/j.1740-8709.2009.00200.x, PMID 20073131
- Aggett, Peter (2010), "Premastication", Maternal and Child Nutrition, Blackwell Publishing Ltd, 6: 2–3, doi:10.1111/j.1740-8709.2009.00226.x
- Levison, Judy; Gillespie, Susan L.; Montgomery, Elizabeth (2011), "Think twice before recommending pre-masticated food as a source of infant nutrition", Maternal & Child Nutrition, Blackwell Publishing Ltd, 7 (1): 104, doi:10.1111/j.1740-8709.2010.00289.x
- Eibl-Eibesfeldt, Irenäus (1971), Love and hate: the natural history of behavior patterns, Aldine Transaction, ISBN 978-0202020389
- Wilson, Edward O. (1980), Sociobiology, Harvard University Press
- Eibl-Eibesfeldt, Irenäus (1983), "Chapter 3: A comparative approach to human ethology", in Rajecki, D. W., Comparing behavior: studying man studying animals, Routledge
- Russon, Anne E.; Bard, Kim A.; Parker, Sue Taylor, Reaching Into Thought:The Minds of the Great Apes, Cambridge University Press, Nov 26, 1998
- Eibl-Eibesfeldt, Irenäus (Oct 30, 2007), Human Ethology, Transaction Publishers, p. 138
- Kirshenbaum, Sheril (Jan 5, 2011), The Science of Kissing: What Our Lips Are Telling Us, Hachette Digital, Inc.
- Radbill, Samuel X. (October 1981), "Infant Feeding through the Ages", CLIN PEDIATR, 20 (10): 613–621, doi:10.1177/000992288102001001
- Soren, David; Soren, Noelle (1999), A Roman Villa and a Late Roman Infant Cemetery:Excavation at Poggio Gramignano, Lugnano in Teverina, L'ERMA di BRETSCHNEIDER
- Forgeng, Jeffrey L.; Singman, Jeffrey L. (1999), Daily Life in Medieval Europe, Greenwood Publishing Group
- Pijoan, M; Elkin, C.A. (1944), "Secondary anemia due to prolonged and exclusive milk feeding among Shoshone indian infants" (PDF), Journal of Nutrition: 67–75
- Jansen, A. A. J.; Parkinson, Susan; Robertson, A. F. S. (1990), Food and Nutrition in Fiji: Food production, composition, and intake, editorips usp.ac.fj, pp. 331–392
- Konner, Melvin (May 31, 2010), The Evolution of Childhood: Relationships, Emotion, Mind, Harvard University Press
- Andrews, Margaret M.; Boyle, Joyceen S. (2008), Transcultural Concepts in Nursing Care (5 ed.), Lippincott Williams & Wilkins
- Sprott, Julie E. (1992), Alaska Native Parents in Anchorage:Perspectives on Childrearing, University Press of America
- Schwartz, Theodore (1975), "Relations among generations in Time-Limited Cultures", Ethnos, 3 (2): 309–322, doi:10.1525/eth.1975.3.2.02a00150
- Bailey, K. V. (1963), "Premastication of infant food in the New Guinea Highlands.", South Pacific Commission, Technical. Information Circular., 61 (1): 1–3
- Nathoo, Tasnim; Ostry, Aleck (Jun 1, 2009), The One Best Way?: Breastfeeding History, Politics, and Policy in Canada, Wilfrid Laurier Univ. Press,
- Pelto, Gretel H.; Habicht, Jean-Pierre (2011), "Letter to the Editor: Discouraging premastication may do more harm than good: Response to the letter by Levison et al. 2010", Maternal and Child Nutrition, 7: 105–106, doi:10.1111/j.1740-8709.2010.00291.x
- Van Esterik, Penny; Williams, Anthony; Fewtrell, Mary S.; Tolboom, Jules J.M.; Lack, Gideon; Penagos, Martin (January 2010), "Commentaries on Premastication: the second arm of infant and young child feeding for health and survival? By Gretel Pelto, Yuanyuan Zhang & Jean-Pierre Habicht", Maternal & Child Nutrition, 6 (1): 19–26, doi:10.1111/j.1740-8709.2009.00227.x