diff --git a/Michelf/Markdown.php b/Michelf/Markdown.php
index 009e39a..efe10c7 100644
--- a/Michelf/Markdown.php
+++ b/Michelf/Markdown.php
@@ -812,7 +812,7 @@ class Markdown implements MarkdownInterface {
 		$idValue = call_user_func($this->header_id_func, $headerValue);
 		if (!$idValue) return "";
 
-		return 'id="' . $this->encodeAttribute($idValue) . '"';
+		return ' id="' . $this->encodeAttribute($idValue) . '"';
 
 	}