diff --git a/crates/bevy_gltf/src/loader.rs b/crates/bevy_gltf/src/loader.rs
index 5f3dd5c321..a16b958870 100644
--- a/crates/bevy_gltf/src/loader.rs
+++ b/crates/bevy_gltf/src/loader.rs
@@ -502,7 +502,17 @@ async fn load_gltf<'a, 'b, 'c>(
                 bevy_utils::tracing::debug!(
                     "Automatically calculating missing vertex normals for geometry."
                 );
+                let vertex_count_before = mesh.count_vertices();
+                mesh.duplicate_vertices();
                 mesh.compute_flat_normals();
+                let vertex_count_after = mesh.count_vertices();
+                if vertex_count_before != vertex_count_after {
+                    bevy_utils::tracing::debug!("Missing vertex normals in indexed geometry, computing them as flat. Vertex count increased from {} to {}", vertex_count_before, vertex_count_after);
+                } else {
+                    bevy_utils::tracing::debug!(
+                        "Missing vertex normals in indexed geometry, computing them as flat."
+                    );
+                }
             }
 
             if let Some(vertex_attribute) = reader