Obesity represents a substantial and continuing health burden in Aotearoa New Zealand, particularly due to conditions such as Type 2 diabetes, hypertension, sleep apnoea, and other obesity-related conditions.
The treatment of obesity has entered a new era in recent times. In New Zealand, the newer effective (incretin-based) weight loss medicines have changed expectations about what medications can achieve. These medicines can produce weight loss without an operation and represent an important advance in management of obesity. However, their emergence should not obscure the established role of keyhole (laparoscopic) weight loss surgery.
For people with severe obesity who meet appropriate clinical criteria, laparoscopic weight loss surgery—particularly sleeve gastrectomy and gastric bypass—has an important potential advantage: it is a one-off intervention capable of producing durable, substantial weight loss and long-term medical benefits, whereas current weight loss medicines generally require continuing longterm treatment to maintain their effect.
Health New Zealand currently reports an average excess weight loss of approximately 15% to 22.5% with weight loss medications over 16 months.
However, these treatments only work while they are being administered. Studies (STEP 1 and SURMONT-4 trials) show that the majority of weight loss is regained within a year of stopping these medications, despite continuing with any lifestyle changes.
A common criticism of weight loss surgery is that it is expensive. That criticism is reasonable if surgery is compared only with the cost of a few months of medication. However, it becomes much less persuasive when treatment is compared over 5 – 10 years.
Surgery in New Zealand
High initial cost – $21,000 – $23,000
Weight loss medication in New Zealand
Indicative private-market prices reported in New Zealand in 2026 for the new (incretin-based) weight loss medicines are approximately NZ$450–800 per month although actual prices vary according to dose, provider and pharmacy.
At NZ$600 per month, for example, ongoing treatment would amount to approximately:
NZ$7,200 per year
NZ$36,000 over five years
NZ$72,000 over ten years
Therefore, the strongest arguments for surgery is not simply that it is cheaper than weight loss medicines longterm, and produces more kilograms of weight loss, ie. 60 -70% excess weight loss for surgery compared to 15-20% excess weight loss with weight loss medicines. But more importantly, that the evidence base for weight loss surgery extends over decades, with sustained weight loss over years, and outcomes such as cure of diabetes, lowering of heart related disease and heart related death.
