Home > Diabetes > Why do blood sugars need to be controlled? Get the Flash Player to see this player. Rate: (Click the stars to rate) Published on Aug 22, 2008 by SSreenan, Views: 3603 Why do blood sugars need to be controlled? In the longterm, if blood sugars are kept under good control, you can decrease the long term complications of diabetes. Blood sugars should be checked with a finger stick blood sugar atleast once a day, and usually more frequently.