diff --git a/lib/modules/http.js b/lib/modules/http.js
index 39c099e..a6b5ea7 100644
--- a/lib/modules/http.js
+++ b/lib/modules/http.js
@@ -214,7 +214,7 @@ module.exports.create = function (deps, conf, greenlockMiddleware) {
     if (conf.http.trustProxy && headers['x-forwarded-proto']) {
       headLines.push('X-Forwarded-Proto: ' + headers['x-forwarded-proto']);
     } else {
-      headLines.push('X-Forwarded-Proto: ' + conn.encrypted ? 'https' : 'http');
+      headLines.push('X-Forwarded-Proto: ' + (conn.encrypted ? 'https' : 'http'));
     }
     var proxyChain = (headers['x-forwarded-for'] || '').split(/ *, */).filter(Boolean);
     proxyChain.push(opts.remoteAddress || opts.address || conn.remoteAddress);