Yes, Rosemary really is a family doctor - in a practice in south London, where she has been working as a part-time partner since 1989.
She qualified from Cambridge, and spent several years training in obstetrics before switching to general practice.
She reckons those years taught her more than just how to deliver a baby:
"I often worked 120 hours a week, and had to keep going through the day and night without a break," she says.
"I learnt very quickly to grab some sleep whenever I could, which is very helpful now! I often have to get up at 4 am for the programme and then go straight to my surgery."
Doctor Rosemary, who works three quarters time as a GP, adds:
"I can't get early nights because my evenings are spent as a cook and chauffeur for my two teenage sons.
"I'm a great siesta fan, as I've discovered the best way to catch up on shut-eye is to have a nap after lunch, before evening surgery.
She tries to practise what she preaches on air, and is keen on keeping fit, especially ski-ing and cycling.
Every year she persuades several of the Breakfast team to join her cycling from London to Brighton for charity.
But she would be the first to admit she drinks too much coffee. She says: "I don't think I'm the only one on the Breakfast team who is guilty of that!"