diff --git a/models/users.js b/models/users.js
index f4f4f38e1..ebb14f5fc 100644
--- a/models/users.js
+++ b/models/users.js
@@ -530,7 +530,8 @@ Users.helpers({
 
   getStartDayOfWeek() {
     const profile = this.profile || {};
-    return profile.startDayOfWeek || 1;
+    // default is 'Monday' (1)
+    return profile.startDayOfWeek ?? 1;
   },
 
   getTemplatesBoardId() {