diff --git a/lib/model.js b/lib/model.js
index 537e1c5..798a96c 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -164,7 +164,7 @@
                         return;
                     }
 
-                    extend(true, entity.data, data);
+                    extend(false, entity.data, data);
 
                     save(entity.key, entity.data, transaction, done);
                 });