You trained as a scientist, why did you move to medicine?
I did natural sciences and specialised in pathology in my final year.
I was tutored by a professor who suggested medicine might be right for me. He recognised that I enjoyed interacting with people and I realised this might be what had been missing in the lab.
I became a GP because I felt a bit cut off in hospital and that you weren't seeing the bigger picture. I felt removed from the context and the reasons why people did things.
Tell us about your current role
I work two and a half days a week at the Prince of Wales Road Group Surgery in north London, where I've worked for the past three years. It is a brilliant place to work and provides excellent care to patients.
I spend the other two and a half days working as a clinical research fellow at the London School of Hygiene and Tropical Medicine.
My research looks at the link between diabetes and TB and involves using the Clinical Research Database of anonymised GP records.
I'm very fortunate to be doing both because they use very different skills and balance each other out nicely.
How did your role as a TV presenter come about?
It happened purely by chance. A friend met an Al Jazeera presenter at a party, who said the channel was developing a series about medical frontiers and boundaries (see box).
They thought doctors might be better at presenting the programmes, because they would know what questions to ask. My friend told him that I might be interested.
Three months later they came to see me with a camera and I did a screen test. I didn't hear anything for a while, so I assumed that they weren't interested.
Then out of the blue I got an email from them asking: 'How do you feel about going to Central America for us?', which of course I was very excited about.
What do your two episodes of the series focus on?
I present two programmes about initiatives in El Salvador - the first is about cervical cancer screening in rural communities and the second, disaster risk reduction.
It was luck, really, which programmes I ended up presenting; they weren't subjects I had a background or a special interest in.
The first episode is about a not for profit organisation, Basic Health International, which is trying to roll out a cervical cancer screening programme to rural communities using a test called careHPV, which screens for HPV DNA.
The test is a swab, so women can do it themselves, and it can be tested at the nearest health centre.
It puts DNA science into a form that can be taken out into rural settings, because it doesn't require access to clean water and electricity, so you don't need a modern laboratory infrastructure.
We met health workers to see how they work, how they attract women to take part in the screening and how they demonstrate using the swab. We also spoke to one of the women and saw how the test was analysed.
We really were in the middle of nowhere - we were travelling in trucks that could barely get up some of the tracks we went along.
The programme on disaster risk reduction is about how El Salvador can reduce loss of life in natural disasters. El Salvador is subject to volcanoes, mudslides, earthquakes, hurricanes. Heavy deforestation has compounded many of the problems the country faces.
The government is working with the charity Plan International to try to reduce the number of lives lost to these disasters. The scheme works with small community groups, which are usually led by a youth member of the community.
The groups repeatedly practise disaster drills, such as what would happen in a mudslide or an earthquake, for example.
They have first aid teams and work out what those initial teams would do and what would happen when the police and the Red Cross arrive.
They regularly practise all stages of coping in a disaster and it has been shown that by being prepared, they can save lives.
What did you learn from your experiences in El Salvador?
I learnt a lot about how the media works. We spent nearly four days filming each programme and it's amazing to watch how they edit it down to the final 10 minutes without losing any of the context.
From a professional point of view, it was an amazing opportunity to step outside my day-to-day practice and see some of the wonderful innovations happening in medicine.
It's quite easy for us to get bogged down in the 'daily grind' of our jobs, but this was a chance to see the benefits of medicine in action - and to feel that, as a doctor, you were part of a bigger picture of people who are trying to advance and improve things for the greater good.
Are you keen to do any more media work in future?
I would like to do more in terms of communicating science in the future. I love trying to explain things to people - to look at what we think is going on and try to explain clearly why this is happening.
The Cure is a new TV series produced by Al Jazeera, looking at hiand low-tech solutions being employed to deal with some of the world's most pressing health problems.
Al Jazeera English is available on Freeview channel 83 and Sky channel 514. You can find out more information and view episodes already shown, including Dr Pealing's programme on cervical screening, at www.aljazeera.com/programmes/TheCURE.