Chewing and its influence on swallowing, gastrointestinal and nutrition-related factors: a systematic review

• Published in: Critical reviews in food science and nutrition Vol. 63; no. 33; pp. 11987 - 12017
• Main Authors: Kumar, Abhishek, Almotairy, Nabeel, Merzo, Juliana Jomaa, Wendin, Karin, Rothenberg, Elisabet, Grigoriadis, Anastasios, Sandborgh-Englund, Gunilla, Trulsson, Mats
• Format: Journal Article
• Language: English
• Published: United States Taylor & Francis 20.12.2023; Taylor & Francis Ltd
• Subjects: Chewing; Chewing efficiency; chewing performance; Deglutition; gastrointestinal disorders; Gastrointestinal system; Gastrointestinal Tract; Health Sciences; Hypotheses; Hälsovetenskap; Mastication; Medical and Health Sciences; Medicin och hälsovetenskap; narrative synthesis; Nutrition; Nutrition and Dietetics; Nutritional Status; Näringslära; oral rehabilitation; Parameters; sensorimotor; Swallowing; videofluorography; narrative synthesis; gastrointestinal disorders; Chewing efficiency; videofluorography; sensorimotor; oral rehabilitation; chewing performance
• ISSN: 1040-8398; 1549-7852; 1549-7852
• DOI: 10.1080/10408398.2022.2098245

The study aimed to evaluate the hypothesis that chewing is a mechanical and physiological contributor to swallowing, physiologic/pathologic processes of the gastrointestinal tract (GIT), and nutrition-related factors. A search strategy was applied to three different databases to investigate if chewing function in adults affects the swallowing, physiologic/pathologic processes of the GIT, and nutrition-related factors compared to controls with no exposure. The included studies were evaluated for methodological quality and risk of bias and certainty of evidence. The results showed 71 eligible studies. Overall, the results showed that 46 studies supported the hypothesis while 25 refuted it. However, the GRADE analysis showed low to very low certainty of the evidence to support the hypothesis that chewing is an important contributor in the swallowing process, and physiologic/pathologic processes in the GIT. The GRADE analysis also showed a moderate to very low certainty of the evidence to suggest that chewing function contributes to nutrition-related parameters. The overall results of the current study showed that a majority (64.7%) of the studies (46 out of 71) supported the hypothesis. However, robust studies with proper design, adequate sample size, and well-defined outcome parameters are needed to establish conclusive evidence.