diff --git a/data/helpers.d/utils b/data/helpers.d/utils
index 2cb18c5c0..4679121e4 100644
--- a/data/helpers.d/utils
+++ b/data/helpers.d/utils
@@ -77,7 +77,7 @@ ynh_backup_before_upgrade () {
 	fi
 
 	# Create backup
-	sudo yunohost backup create --ignore-system --apps $app --name $app_bck-pre-upgrade$backup_number
+	sudo BACKUP_CORE_ONLY=1 yunohost backup create --ignore-system --apps $app --name $app_bck-pre-upgrade$backup_number
 	if [ "$?" -eq 0 ]
 	then
 		# If the backup succeeded, remove the previous backup