Thirty-one gastric bypass operations were performed in the Southern District Health Board area in 2011-12, thanks to special funding, Southland Hospital bariatric surgeon Mark Smith says.
Mr Smith started a new weight-loss surgery service this year in Southland, helping the DHB use its share of $8 million over four years allocated in 2010 to boost the surgery.
The previous year, the DHB performed just 12 weight-loss surgeries, all in Dunedin.
Mr Smith said he was working effectively with Dunedin bariatric surgeon Prof Andre van Rij, with whom he was delivering a unified service with a single waiting list.
The pair also operated on some patients from other district health boards.
Before moving to Southland last year, Mr Smith worked in Portland, Oregon, where for three years he performed weight-loss surgery.
At Southland, he also performed general surgery.
In the United States, bariatric surgery was much more common, because insurance companies and the Government saw its benefit for reducing the complications and costs of obesity.
In New Zealand, it had traditionally not been well funded, so it was "fantastic to have ring-fenced money to put towards it".
The percentage of the population with obesity was about the same in Portland as in New Zealand, he said.
Surgery led to "dramatic health improvements", including a 40% drop in mortality over seven years.
About 80% of patients were female, despite the fact obesity affected both genders equally.
The procedure was viewed as a "last resort" by most patients, who on average lost a third of their body-weight over the 18 months after surgery.
The surgery resolved type 2 diabetes in 80% of patients, as well as relieving joint pain and improving mobility and general quality of life.
In the 10 bypasses he had performed at Southern DHB, the youngest patient was 24, and the oldest 58.
A Ministry of Health spokesman was happy the number of weight-loss surgeries nationally had increased, as expected, with the extra funding.
The National Health Board focus was to improve access in areas where uptake had been slower than expected, he said.
