Mechanisms by which cocoa flavanols improve metabolic syndrome and related disorders  Karen M. Strat, Thomas J. Rowley, Andrew T. Smithson, Jeffery S. Tessem, Matthew W. Hulver, Dongmin Liu, Brenda M. Davy, Kevin P. Davy, Andrew P. Neilson  Journal of Nutritional Biochemistry  Volume 35, Pages 1-21 (September 2016) DOI: 10.1016/j.jnutbio.2015.12.008 Copyright © 2016 Elsevier Inc. Terms and Conditions

Fig. 1 The basic 3-ring flavonoid skeleton (A), the C3-hydroxylated flavanol skeleton (B) and structures of predominant flavanol monomers in cocoa (+) catechin, (−)-catechin and (−)-epicatechin (C). Journal of Nutritional Biochemistry 2016 35, 1-21DOI: (10.1016/j.jnutbio.2015.12.008) Copyright © 2016 Elsevier Inc. Terms and Conditions

Fig. 2 Representative structure of cocoa B-type procyanidins. Journal of Nutritional Biochemistry 2016 35, 1-21DOI: (10.1016/j.jnutbio.2015.12.008) Copyright © 2016 Elsevier Inc. Terms and Conditions

Fig. 3 Hypothetical mechanisms by which cocoa flavanols may affect carbohydrate digestion. Mechanisms include inhibiting digestive enzymes α-amylase and α-glucosidase, inhibiting glucose transporters SGLT1 and GLUT2, promoting GLP-1 secretion and inhibiting DPP-4. Journal of Nutritional Biochemistry 2016 35, 1-21DOI: (10.1016/j.jnutbio.2015.12.008) Copyright © 2016 Elsevier Inc. Terms and Conditions

Fig. 4 Suggested mechanism by which increased gut permeability and endotoxin levels lead to insulin resistance. Journal of Nutritional Biochemistry 2016 35, 1-21DOI: (10.1016/j.jnutbio.2015.12.008) Copyright © 2016 Elsevier Inc. Terms and Conditions

Fig. 5 One mechanism by which a chronic cocoa supplement may improve glucose homeostasis. Cocoa may improve gut barrier function, leading to a reduction in serum endotoxin, minimizing inflammation, allowing for normalized glucose control. Journal of Nutritional Biochemistry 2016 35, 1-21DOI: (10.1016/j.jnutbio.2015.12.008) Copyright © 2016 Elsevier Inc. Terms and Conditions