Before the discovery of insulin in 1922, DM treatment was mainly by dietary manipulation and plant therapies. Nowadays, it is generally accepted that plant-derived foods have health-promoting properties that depend on their nutritional value , and more than 400 plants have been introduced as herbal medicines for the treatment of diabetes. In particular, epidemiological studies strongly suggest that high intake of whole grain foods and legumes reduces the development
of type 2 DM. This shows that the intake of whole grain foods and legumes is beneficial for the prevention and management of DM.