diff --git a/metatag.module b/metatag.module
index f94f4fe..6e888fd 100644
--- a/metatag.module
+++ b/metatag.module
@@ -542,8 +542,12 @@ function metatag_entity_insert($entity, $entity_type) {
  * Implements hook_entity_update().
  */
 function metatag_entity_update($entity, $entity_type) {
-  list($id) = entity_extract_ids($entity_type, $entity);
+  
+  if (!metatag_entity_supports_metatags($entity_type)) {
+    return;
+  }
 
+  list($id) = entity_extract_ids($entity_type, $entity);
   if (isset($entity->metatags)) {
 
     // Determine the language as per http://drupal.org/node/1626346.