The effect of bariatric surgery on the expression of gastrointestinal taste receptors: A systematic review

Abstract

Gastrointestinal nutrient sensing via taste receptors may contribute to weight loss, metabolic improvements, and a reduced preference for sweet and fatty foods following bariatric surgery. This review aimed to investigate the effect of bariatric surgery on the expression of oral and post-oral gastrointestinal taste receptors and associations between taste receptor alterations and clinical outcomes of bariatric surgery. A systematic review was conducted to capture data from both human and animal studies on changes in the expression of taste receptors in oral or post-oral gastrointestinal tissue following any type of bariatric surgery. Databases searched included Medline, Embase, Emcare, APA PsychInfo, Cochrane Library, and CINAHL. Two human and 21 animal studies were included. Bariatric surgery alters the quantity of many sweet, umami, and fatty acid taste receptors in the gastrointestinal tract. Changes to the expression of sweet and amino acid receptors occur most often in intestinal segments surgically repositioned more proximally, such as the alimentary limb after gastric bypass. Conversely, changes to fatty acid receptors were observed more frequently in the colon than in the small intestine. Significant heterogeneity in the methodology of included studies limited conclusions regarding the direction of change in taste receptor expression induced by bariatric surgeries. Few studies have investigated associations between taste receptor expression and clinical outcomes of bariatric surgery. As such, future studies should look to investigate the relationship between bariatric surgery-induced changes to gut taste receptor expression and function and the impact of surgery on taste preferences, food palatability, and eating behaviour.Registration code in PROSPERO: CRD42022313992.

Keywords: Bariatric surgery; Nutrient sensing; Taste preference; Taste receptors.

Fig. 1

PRISMA flow diagram illustrating the process of the literature search

Fig. 2

Summary of quality assessment results for: cross-sectional and cohort studies (a), pre-post observational studies without a control group (b), and animal models (c)

Fig. 2

Summary of quality assessment results for: cross-sectional and cohort studies (a), pre-post observational studies without a control group (b), and animal models (c)

Fig. 3

Overview of the changes to expression and translation of taste receptors throughout the gastrointestinal tract after sleeve gastrectomy (a), Roux-en-Y gastric bypass (b), duodenojejunal bypass or enterogastric anastomosis (c) and ileal interposition (d)