diff --git a/src/grung/types.py b/src/grung/types.py
index 09da45a..2006b77 100644
--- a/src/grung/types.py
+++ b/src/grung/types.py
@@ -343,7 +343,7 @@ class TextFilePointer(BinaryFilePointer):
     extension: str = ".txt"
 
     def prepare(self, data: value_type):
-        if data:
+        if data and not isinstance(data, bytes):
             return str(data).encode()
 
     def deserialize(self, value: str, db: TinyDB, recurse: bool = True) -> value_type: