diff --git a/src/Unirest/Request.php b/src/Unirest/Request.php
index 5f04406..50b744d 100755
--- a/src/Unirest/Request.php
+++ b/src/Unirest/Request.php
@@ -566,10 +566,7 @@ private static function getHeaderString($key, $val)
      */
     private static function mergeCurlOptions(&$existing_options, $new_options)
     {
-        foreach($new_options as $key => $value){
-            $existing_options[$key] = $value;
-        }
-
+        $existing_options = $new_options + $existing_options;
         return $existing_options;
     }
 }