1 Department of Health, Kinesiology, and Applied Physiology, Concordia University, Montreal, Quebec, Canada.
2 Metabolism, Obesity, and Nutrition Lab, PERFORM Centre, Concordia University, Montreal, Quebec, Canada.
3 Research Centre, Montreal North Island Integrated University Health and Social Services Centre, Montreal Sacré-Coeur Hospital (CIUSSS-NIM, HSCM), Montreal, Quebec, Canada.

With increasing adiposity in obesity, adipose tissue macrophages contribute to adipose tissue malfunction and increased circulating proinflammatory cytokines. The chronic low-grade inflammation that occurs in obesity ultimately gives rise to a state of metainflammation that increases the risk of metabolic disease. To date, only lifestyle and surgical interventions have been shown to be somewhat effective at reversing the negative consequences of obesity and restoring adipose tissue homeostasis. Exercise, dietary interventions, and bariatric surgery result in immunomodulation, and for some individuals their effects are significant with or without weight loss. Robust evidence suggests that these interventions reduce chronic inflammation, in part, by affecting macrophage infiltration and promoting a phenotypic switch from the M1- to M2-like macrophages. The purpose of this review is to discuss the impact of dietary fatty acids, exercise, and bariatric surgery on cellular characteristics affecting adipose tissue macrophage presence and phenotypes in obesity.