diff --git a/src/wp-includes/user-functions.php b/src/wp-includes/user-functions.php
index fd73875958..9e95bee6c7 100644
--- a/src/wp-includes/user-functions.php
+++ b/src/wp-includes/user-functions.php
@@ -1102,9 +1102,18 @@ function sanitize_user_field($field, $value, $user_id, $context) {
  *
  * @since 3.0.0
  *
- * @param object $user User object to be cached
+ * @param object|WP_User $user User object to be cached
+ * @return bool|null Returns false on failure.
  */
-function update_user_caches($user) {
+function update_user_caches( $user ) {
+	if ( $user instanceof WP_User ) {
+		if ( ! $user->exists() ) {
+			return false;
+		}
+
+		$user = $user->data;
+	}
+
 	wp_cache_add($user->ID, $user, 'users');
 	wp_cache_add($user->user_login, $user->ID, 'userlogins');
 	wp_cache_add($user->user_email, $user->ID, 'useremail');
diff --git a/tests/phpunit/tests/user/updateUserCaches.php b/tests/phpunit/tests/user/updateUserCaches.php
index 98d14a6248..f4b0856834 100644
--- a/tests/phpunit/tests/user/updateUserCaches.php
+++ b/tests/phpunit/tests/user/updateUserCaches.php
@@ -50,4 +50,21 @@ class Tests_User_UpdateUserCaches extends WP_UnitTestCase {
 
 		$this->assertEquals( 12345, wp_cache_get( 'bar', 'userslugs' ) );
 	}
+
+	/**
+	 * @ticket 24635
+	 */
+	public function test_should_store_raw_data_in_users_bucket_when_passed_a_wp_user_object() {
+		global $wpdb;
+
+		$u = $this->factory->user->create();
+		$raw_userdata = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $wpdb->users WHERE ID = %d", $u ) );
+		$user_object = new WP_User( $u );
+
+		update_user_caches( $user_object );
+
+		$cached = wp_cache_get( $u, 'users' );
+		$this->assertFalse( $cached instanceof WP_User );
+		$this->assertEquals( $raw_userdata, $cached );
+	}
 }