diff --git a/app/controllers/api/v1/contact_controller.rb b/app/controllers/api/v1/contact_controller.rb
index 3b24ba7..4807814 100644
--- a/app/controllers/api/v1/contact_controller.rb
+++ b/app/controllers/api/v1/contact_controller.rb
@@ -97,7 +97,7 @@ module Api
       # Detecta si la dirección de contacto es válida.  Además es
       # opcional.
       def from_is_address?
-        return if contact_params[:from].empty?
+        return if contact_params[:from].blank?
         return if EmailAddress.valid? contact_params[:from]
 
         head :precondition_required