At £150-300 per month for private treatment, GLP-1 medications aren't cheap. But when you consider what obesity costs — in health, quality of life, and actual money — the calculation is more nuanced than it first appears.
What obesity costs the NHS
The NHS spends an estimated £11.4 billion per year on obesity-related conditions — including Type 2 diabetes, cardiovascular disease, joint replacements, and cancer. The cost of rolling out Mounjaro on the NHS is estimated at approximately £317 million per year by year three of the programme — a fraction of what obesity-related care costs.1
What obesity costs individuals
Beyond NHS costs, obesity carries personal financial costs that are rarely calculated: higher health insurance premiums (for those with private insurance), lost earnings from obesity-related health issues, costs of managing comorbidities (blood pressure medication, diabetes medication, CPAP machines), costs of larger clothing, reduced mobility affecting work capacity, and mental health treatment costs related to weight stigma and low self-esteem.
The GLP-1 cost-benefit calculation
A year of private Mounjaro treatment costs approximately £2,000-3,600. Consider what that investment might offset: reduced or eliminated need for blood pressure medication, improved or resolved Type 2 diabetes (potentially eliminating diabetes medication costs), reduced risk of joint replacement surgery, reduced risk of heart attack or stroke (and associated treatment and recovery costs), improved sleep apnoea (potentially eliminating CPAP costs), and improved mental health and productivity.
For the NHS, NICE specifically evaluated tirzepatide as cost-effective — meaning the health benefits justify the expenditure compared to alternatives. This analysis considered not just the direct cost of the medication but the savings from prevented obesity-related illness downstream.
The caveat
The cost-benefit only holds if treatment produces sustained weight loss. Given the evidence that most people regain weight after stopping, the economic argument increasingly supports long-term treatment — which means long-term cost. Whether private treatment at £200+/month is sustainable indefinitely is a personal financial question that each individual needs to consider carefully.