diff --git a/mne_bids/path.py b/mne_bids/path.py
index d05f01b47..cb72f02dd 100644
--- a/mne_bids/path.py
+++ b/mne_bids/path.py
@@ -959,6 +959,8 @@ def update(self, *, check=None, **kwargs):
                 )
 
             if ENTITY_VALUE_TYPE[key] == "label":
+                if isinstance(val, int):
+                    val = str(val)
                 _validate_type(val, types=(None, str), item_name=key)
             else:
                 assert ENTITY_VALUE_TYPE[key] == "index"