Store a single byte in a protobuf message

Question

What data type do I use to store a single byte in a protocol buffer message? Seeing the list at https://developers.google.com/protocol-buffers/docs/proto#scalar it seems like on

Answer 1

Well you need to understand that it will take at least two bytes anyway - one for the tag and one for the data. (The tag will take more space if the field number is high.) If you use uint32, it will take 1 byte for the data for values up to 127, and 2 bytes for anything larger.

I don't believe there's anything that will be more efficient than that.