This is a market analysis and its findings — built from public data (search, AI answers, reviews, video, forums), not a delivered client result. Every number below is measured from that corpus, July 2026.
The market in one paragraph
UK private weight-loss treatment is a three-actor market: the molecules (Mounjaro, Wegovy, Ozempic and the next wave), the retailers (Boots and Superdrug's online doctors, pure-play pharmacies, telehealth programmes) and the unbranded category both sides compete to capture. We measured all three across two surfaces — classic Google Search and the AI-answer layer — and the headline is stark: demand speaks in product names, but the visibility that converts it is being re-ranked by AI answers, and the biggest loser is the NHS itself.
Four findings
1. The demand race has a runaway leader. Mounjaro draws 1.87M UK searches a month — five times Wegovy's 370K and eight times Ozempic's 234K. Molecule-branded demand is the largest and fastest-growing class of the 8.5M monthly total (2.8M vs 5.2M generic and 0.5M retailer-brand). The next wave is already visible: retatrutide, not yet launched, pulls ~90K searches a month on just 11 keywords, while Saxenda has collapsed to 2.1K — this category churns fast enough that a static report is stale in a quarter.
2. The funnel converts through content, not checkout. Treatment research carries ~2.8M monthly searches; transactional purchase terms carry under 2K. Patients research eligibility, dosing, side effects and price — then convert wherever that research led them. Providers have colonised the research layer (61% of its visibility); the NHS gates only the eligibility question (52%).
3. AI answers re-rank the market. Comparing each domain's share of classic Search against its share of AI-answer citations: NHS.uk holds 15.4% of Search but only 1.5% of AI citations. Superdrug's online doctor drops 6.1 points, Asda's 4.7. The winners are regulators (NICE: zero Search presence, 5.4% of AI citations) and agile players (Second Nature, medino). High-street brands out-rank pure-play pharmacies 6-to-1 in classic Search — in AI answers the gap nearly closes. A Google ranking does not transfer to the AI layer.
4. Perception has a moat, and it isn't efficacy. Every molecule scores well on results. The divergence is weight regain after stopping: Mounjaro +0.45 sentiment vs semaglutide's −0.34 (scale −1 to +1, from 79,000 evidence snippets). "Keeping it off" is the conversation that decides switching — and the manufacturers, barred by UK law from consumer advertising of prescription medicines, hold just 1.45% of Search visibility over the demand their own brands create.
The method, briefly
Demand is measured, not estimated from a tool's index: an 87-month (2019–2026) Google Trends × Google Ads co-measurement across all 1,773 keywords, so every trajectory in the study is real monthly variation. Visibility is CTR-weighted Search share plus AI-answer citation share, per domain, measured July 2026. Perception is 79,000 evidence snippets from reviews, YouTube, forums and articles — every claim in the study traces back to quoted evidence. That groundedness is the same standard we apply to the content we build from studies like this.
Interrogate it yourself
The full study corpus is live behind a scoped analyst chatbot — ask it anything about this market and it answers only from the evidence: open the weight-loss study chatbot.