Mr Ackroyd has become more weight conscious himself

I am a consultant in general and upper gastroenterology and a bariatric, or obesity surgeon.

I work at the NHS hospital, the Royal Hallamshire and in the private sector for the BMI Thornbury.

My job is almost entirely dealing with upper gastroenterology problems, such as cancer of the oesophagus, the stomach, reflux and obesity surgery.

My work is about one third cancers, one third obesity and one third benign conditions.

These days it is definitely the obesity work.

There is an obesity epidemic.

I am at capacity now and I can't do any more Roger Ackroyd

And because of a growing awareness by people and GPs, more people are looking at surgical options.

In my obesity work this is 99% gastric banding or gastric bypasses.

Through keyhole surgery we can put a band around the stomach, which restricts what a patient can eat, so they lose weight. The gastric bypass is a more complicated procedure, but even this we can do by keyhole surgery.

This procedure takes about an hour, compared to the band, which takes about half an hour. We did about 350 of these operations last year.

Obesity 1.2 million people in the UK are considered morbidly obese, with a body mass index of over 40 (20-25 is healthy) Many have associated problems such as arthritis, type 2 diabetes, hypertension and heart and lung problems

Following the NICE guidelines you are eligible for the treatment if you have a body mass index (BMI) of 40, or 35 if you have an additional condition such as diabetes, or asthma.

There is a problem with the NHS at the moment. I do think it is a problem of capacity rather than funding, but despite the NICE guidelines we cannot take patients now unless they have a BMI of 50 or more, or 45, with problems.

Juggling my time. I am constantly busy doing two things at once, there are not enough hours in the day. And it is going to get worse. I am at capacity now and I can't do any more.

I am sure there are going to be more obesity surgeons in the future to meet demand. We are currently looking at training and getting people accredited.

There have been a lot of satisfying cases. People who are 29 or 30 stones are pretty immobile.

Once they have had surgery, we see them regularly over a period of 18 months and watch their weight steadily decrease to about 11 stones.

I've had patients with fertility problems who have reduced their weight and then gone on to have babies.

Then there are the patients who lose so much weight that you don't recognise them when they come back for a review.

These are often younger people with a major problem with their weight and we can change their lives.

I also operate on people with cancer of the oesophagus or stomach, the difference is that despite your very best efforts, their cancer may be too advanced and they still may die.

I am not saying that this means we should not operate, what I am saying is that with obesity surgery there is far more scope to change a patient's life and you can see a very real difference both physically and emotionally.

I am not quite sure. I am not quite sure how I ended up doing medicine, or how I ended up in this speciality.

I suppose I got into surgery because it interested me and I worked for a couple of guys who did obesity surgery so I took it on myself, but it was not a conscious decision.

Since doing this job I have lost weight. I did not have to lose weight, but because you are working with people with obesity you do become more conscious about what you are eating.

No, I feel very lucky that things have worked out as they have.

I think I would like to see the service expand and to expand the research work.

CV - Mr Roger Ackroyd

1989: Qualified Sheffield University

1994: Gained surgeon's qualifications (FRCS)

2001: Made a consultant