Does anyone know the story/episode where it actually *said* the Doctor has a lower body temperature than humans?

I happen to have been going through transcripts of the classic series (the site is at http://www.chakoteya.net/DoctorWho/index.htm) for a while now. I'm well into Four's era, and haven't seen anything about it yet. The two hearts, yes; respiratory bypass, yes; allergy to aspirin, yes; body temperature, no. But then I haven't been looking specifically for that information, just quotes for my collection.