Landmark study finds British patients have lost over 4.2 million kilograms in GLP-1 revolution

ZAVA and Asda Online Doctor release a first-ever joint analysis of half a million British patients, revealing weight-loss jabs match or exceed clinical trial results. The data shows women accessing treatment at 3.5x the rate of men, with the North East outpacing the rest of the country.

British patients using GLP-1 weight-loss injections privately have collectively shed over 4.2 million kilograms since Wegovy launched in late 2023 — equivalent in weight to 53,500 average adults — according to the largest-ever analysis of real-world GLP-1 use in the United Kingdom.

Signal in the Food Noise draws on half a million patient journeys and over 2.3 million treatments from Asda Online Doctor and the online doctor service ZAVA (representing ~20% of the UK private market) to map, for the first time, how Mounjaro and Wegovy are performing outside clinical trial settings.

Real-world results match or exceed clinical trials. Mounjaro users achieved median weight loss of 22.1% at 72 weeks; Wegovy users achieved 16.0% at 68 weeks. Among those who persisted for one year, more than half of patients who started with obesity exited obesity entirely.

2025: The Year GLP-1s Went Mainstream

The report captures a year of explosive growth:

1. New patients up 222% vs 2024
2. Total weight lost up 317%
3. Treatments processed up 359%

At peak demand (August 2025): one new sign-up every 54 seconds. Over the two-year period, weight was being lost at an average rate of 211.8 kg per hour.

The Gender Gap

Women make up 77.6% of patients — despite obesity rates being similar between genders. At identical starting BMI levels, women access treatment at 3.5 times the rate of men.

The gap may be narrowing (down from 81.5% in early 2025), but remains far wider than Germany’s 2:1 ratio — suggesting UK-specific factors are at play.

A potential clue from survey data: women report ‘constant’ intrusive food thoughts at three times the rate of men (61% vs 20%).

The Geography of GLP-1s

Mapping uptake across 93% of UK local authorities reveals a striking northern tilt:

1. North East leads at 107.3 patients per 10,000 (+47% vs national average)
2. Among major population centres (250,000+), Nottingham tops the table at 138.4 per 10,000 — 90% above average
3. Milton Keynes breaks the northern pattern at 110.1 per 10,000 (+51%)

Areas with the highest obesity rates show 1.6x the uptake of low-obesity areas — suggesting access is following clinical need, not simply affluence.

Yet some patterns defy expectations. Brighton & Hove has one of Britain’s lowest obesity rates (15.1%), yet records nearly double the GLP-1 uptake of similar areas. Bristol (below-average obesity) sits 47% above the national average.

Beyond the Scales

The effects aren’t just physical. Before treatment, 90% of surveyed patients reported frequent or constant food-related thoughts. On medication, 96% experienced some reduction — with over three-quarters reporting significant relief or complete elimination.

Among drinkers, 63% reported reduced desire for alcohol. Some 41% noticed diminished urges for impulse shopping.

Overall, 70% of current users say treatment is ‘definitely worth it.’

Signal in the Food Noise analyses over 500,000 patient journeys and more than 2.3 million treatments (September 2023–November 2025), plus a survey of 384 UK GLP-1 users across multiple providers.

Key Statistics

• Average starting BMI: 36.2 (Class II Obesity)
• Patients carry 25–30kg more than the average Briton
• ~60% cite failed diets as primary motivation (ahead of appearance)
• Median time to 5% weight loss: 6 weeks
• Median time to 10% weight loss: 12 weeks
• Nearly 80% report saving money on food — yet cost remains #1 reason for stopping (51%)

Top Local Authorities by GLP-1 Uptake (population 250,000+)

Cumulative GLP-1 Patients Per 10,000 Population (Mounjaro and Wegovy)

Asda Online Doctor and ZAVA are two of the UK’s leading telehealth services, united by a shared, CQC-registered clinical infrastructure and a commitment to providing quick, secure, and accessible medical care, 365 days a year. Since September 2023, this infrastructure has collectively supported over 500,000 patients accessing Mounjaro and Wegovy.

For more details, including references and methodologies, see the full report or get in touch.

Media Contact: [email protected]

This report is an exploratory analysis of real-world data and should not be used to inform individual treatment decisions or clinical guidelines.