diff --git a/htdocs/core/actions_addupdatedelete.inc.php b/htdocs/core/actions_addupdatedelete.inc.php
index 754d2460fc9..18ecc3db457 100644
--- a/htdocs/core/actions_addupdatedelete.inc.php
+++ b/htdocs/core/actions_addupdatedelete.inc.php
@@ -130,8 +130,8 @@ if ($action == 'update' && !empty($permissiontoadd))
 		}
 		elseif ($object->fields[$key]['type'] == 'boolean') {
 			if (!GETPOSTISSET($key)) {
-				$object->$key = null;
-				continue; // The field was not submited to be edited
+				$object->$key = 0; // use 0 instead null if the field is defined as not null 
+				continue; 
 			}
 		}