diff --git a/index.js b/index.js
index 640c24c..36e7e5d 100644
--- a/index.js
+++ b/index.js
@@ -2,13 +2,16 @@
 exports = module.exports = trim;
 
 function trim(str){
+  if (str.trim) return str.trim();
   return str.replace(/^\s*|\s*$/g, '');
 }
 
 exports.left = function(str){
+  if (str.trimLeft) return str.trimLeft();
   return str.replace(/^\s*/, '');
 };
 
 exports.right = function(str){
+  if (str.trimRight) return str.trimRight();
   return str.replace(/\s*$/, '');
 };