diff --git a/src/utils/utils.rs b/src/utils/utils.rs
index e2ad7c0ba8..84588d8775 100644
--- a/src/utils/utils.rs
+++ b/src/utils/utils.rs
@@ -221,8 +221,12 @@ fn download_file_(
     // Download the file
 
     // Keep the curl env var around for a bit
-    let use_curl_backend = process().var_os("RUSTUP_USE_CURL").is_some();
-    let use_rustls = process().var_os("RUSTUP_USE_RUSTLS").is_some();
+    let use_curl_backend = process()
+        .var_os("RUSTUP_USE_CURL")
+        .map_or(false, |it| it != "0");
+    let use_rustls = process()
+        .var_os("RUSTUP_USE_RUSTLS")
+        .map_or(true, |it| it != "0");
     let (backend, notification) = if use_curl_backend {
         (Backend::Curl, Notification::UsingCurl)
     } else {