Oregano and rosemary turn out to be packed with healthful compounds that may work in much the same way as prescription anti-diabetic medication in keeping their blood-sugar level in check. While greenhouse-grow herbs contained more polyphenols and flavonoids compared to the equivalent commercial dried herbs, commercial extracts of Greek oregano, Mexican oregano and rosemary were better inhibitors of the enzyme, required to reduce risk of type-2 diabetes.
Bower, A. M., Real Hernandez, L. M., Berhow, M. A., & de Mejia, E. G. (2014). Bioactive Compounds from Culinary Herbs Inhibit a Molecular Target for Type 2 Diabetes Management, Dipeptidyl Peptidase IV. Journal of Agricultural and Food Chemistry, 62(26), 6147–6158. http://doi.org/10.1021/jf500639f