How to create command button and run from the ribbon?

Is it true that I have to enable macro and choose to trust access to the VBA project object model in order to create and run macros? It seems there is some security risk associated with making the workbook as macro enabled. What makes the commands run from the ribbon security free? Is it true that we can work around the macro security concern by creating a command button to the ribbon and run the macro from the command button? If yes, how come I could not find any discussion of creating the command buttons? I am using Excel 2007.