diff --git a/token.test b/token.test
index 4ffec93..27278b7 100644
--- a/token.test
+++ b/token.test
@@ -430,6 +430,13 @@ class TokenMenuTestCase extends TokenTestHelper {
       'menu-link:root:mlid' => $root_link['mlid'],
     );
     $this->assertTokens('node', array('node' => $node), $tokens);
+
+    // Test [node:menu] tokens for a loaded node. A loaded node object has not
+    // "menu" variable.
+    $loaded_node = node_load($node->nid);
+    $tokens = array();
+    $this->assertTokens('node', array('node' => $loaded_node), $tokens);
+    $this->assertFalse(isset($loaded_node->menu), t("Make sure \$node->menu variable is not set in a loaded node object after token generation for it."), 'Oteher');
   }
 }
 
diff --git a/token.tokens.inc b/token.tokens.inc
index e382a0b..6ac81e1 100644
--- a/token.tokens.inc
+++ b/token.tokens.inc
@@ -1043,10 +1043,17 @@ function menu_tokens($type, $tokens, array $data = array(), array $options = arr
     if (!isset($node->menu)) {
       // Nodes do not have their menu links loaded via menu_node_load().
       menu_node_prepare($node);
+      $mlid = $node->menu['mlid'];
+      // menu_node_prepare() set the $node->menu variable, but this token
+      // function should not change the node object.
+      unset($node->menu);
+    }
+    elseif (!empty($node->menu['mlid'])) {
+      $mlid = $node->menu['mlid'];
     }
 
-    if (!empty($node->menu['mlid'])) {
-      $link = token_menu_link_load($node->menu['mlid']);
+    if (isset($mlid)) {
+      $link = token_menu_link_load($mlid);
 
       foreach ($tokens as $name => $original) {
         switch ($name) {