Testing times for Lady Boothroyd

Image caption Lady Boothroyd and Prof Tim Spector

Despite undergoing open-heart surgery two years ago, our guest editor Baroness Boothroyd is, at 82, in fine fettle - something those who meet her often comment on.

But why is that? Is she reaping the rewards of a good diet and healthy lifestyle, or is she just one of the lucky ones who owes her longevity and robust health to "good genes"?

Lady Boothroyd wanted to know what the world of biomedical science had to say about it - but you have to be careful what you wish for when editing this programme - and I don't think she was expecting to become the guinea pig in a scientific study when she agreed to meet the director of Kings College London's Department of Twin Research and Genetic Epidemiology, professor Tim Spector, at St Thomas' Hospital shortly before Christmas.

Professor Spector is one of the world's leading experts on aging and had prepared a battery of tests and scans to assess Lady Boothroyd's susceptibility to age-related decline.

He's particularly interested in the interplay between nature and nurture, and the role that environmental factors like diet, exercise and exposure to toxins can play in switching genes on and off. We'll hear more about these epigenetic factors in aging when the results of Lady Boothroyd's blood tests are back in the new year.

Watch this space.