diff --git a/lib/proxy/proxy.js b/lib/proxy/proxy.js
index 450cd75..fd7799e 100644
--- a/lib/proxy/proxy.js
+++ b/lib/proxy/proxy.js
@@ -7,13 +7,13 @@ function proxyHeaders(req) {
     });
 
     if (
-        !headers["x-forwarded-for"] !== undefined &&
+        !headers["x-forwarded-for"] === undefined &&
         req.connection !== undefined &&
         req.connection.remoteAddress !== undefined
     ) {
         headers["x-forwarded-for"] = req.connection.remoteAddress;
     }
-    if (!headers["x-forwarded-proto"] !== undefined && req.protocol !== undefined) {
+    if (!headers["x-forwarded-proto"] === undefined && req.protocol !== undefined) {
         headers["x-forwarded-proto"] = req.protocol;
     }