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Real patients

Lose weight, gain

It's more than the number on the scales — in their own words.

Jessica, PPRX patient — before and after losing 26.9 kg in 9 months

Jessica

↓ 26.9 kg

“I stopped planning my whole day around food. The noise just went quiet — and for the first time in years I felt like myself again.”

PPRX member · weight-loss programme · 9 months

Andrew, PPRX patient — before and after losing 22.5 kg in 11 months

Andrew

↓ 22.5 kg

“I'd tried every diet going. This was the first time it didn't feel like a fight — the weight came off while life carried on.”

PPRX member · weight-loss programme · 11 months

Stacey, PPRX patient — before and after losing 31.4 kg in 12 months

Stacey

↓ 31.4 kg

“My son noticed before I did. Keeping up with him used to wear me out — now it's the best part of my day.”

PPRX member · weight-loss programme · 12 months

Jeff, PPRX patient — before and after losing 38 kg in 14 months

Jeff

↓ 38 kg

“Thirty-eight kilos in fourteen months. Not a crash diet, not a bootcamp — just steady, honest progress with people checking in on me.”

PPRX patient · weight-loss programme · 14 months

Weight-loss medication works alongside diet and activity — individual results vary

What to expect

How long until you see results?

In clinical trials, GLP-1 treatment produced steady, compounding weight loss over the first year — steepest at the start, settling as you approach your new weight. Here's the honest shape of it.

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Today – 3 months

~5%body weight12

  • Treatment begins at the lowest dose, stepping up roughly monthly as your body adjusts.
  • Most people notice appetite quietening within the first few weeks.

3 – 6 months

~10%body weight12

  • Steady, visible progress as the dose reaches maintenance levels.
  • Habits built alongside — protein, movement, sleep — start carrying their own weight.

6 – 12 months

15–20%body weight12

  • Trial averages reach around 15% (semaglutide) to 20% (tirzepatide) of body weight over a year or more.
  • The goal shifts from losing weight to keeping it off — with a plan for maintenance.
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BMI, answered

Your BMI questions,
answered.

What BMI can tell you, what it can't, and where the thresholds for treatment actually sit. A clinician answers the rest, by name.

❏Seven honest answers
How is BMI calculated?
BMI (body mass index) is your weight in kilograms divided by your height in metres squared. Someone who is 1.70 m and 95 kg has a BMI of 95 ÷ (1.70 × 1.70) = 32.9. Our calculator does the conversion for you — enter your weight in kilograms, pounds or stone, and your height in centimetres or feet and inches.
What do the BMI categories mean?
The NHS bands are: under 18.5 underweight, 18.5–24.9 healthy weight, 25–29.9 overweight, and 30+ obese. They're a population-level screening tool — a starting point for a clinical conversation, not a diagnosis.
What are the limits of BMI?
BMI can't tell muscle from fat, so very muscular people can score 'overweight' while carrying little fat. NICE also advises lower thresholds for people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean backgrounds, whose health risks rise at lower BMIs. That's why a prescriber reviews the whole picture, not just the number.
What BMI do I need for weight-loss medication?
The licensed criteria are a BMI of 30 or higher, or 27 or higher alongside a weight-related condition such as hypertension, type 2 diabetes or sleep apnoea. Below those thresholds our prescribers won't issue a GLP-1 prescription — the consultation confirms suitability either way.
Is BMI different for men and women?
The calculation and NHS categories are the same for adult men and women. Body composition differs between sexes, which is one of BMI's known limitations — another reason it's used as a screen rather than a verdict.
How much weight could I lose on Mounjaro or Wegovy?
Trial averages range from around 15% of body weight with semaglutide (Wegovy, STEP 1) to around 20% with tirzepatide (Mounjaro, SURMOUNT-1) over a year or more, alongside diet and activity. Individual results vary — some lose more, some less.
What if my BMI is below 27?
We won't prescribe weight-loss medication — it isn't licensed, or healthy, below the thresholds. If you'd still like structured support, our coaching plans (meal planning and training) are available without a prescription, and your GP is the right first step if your weight worries you in either direction.

References

  1. 1.Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). New England Journal of Medicine, 2021. nejm.org/doi/full/10.1056/NEJMoa2032183
  2. 2.Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). New England Journal of Medicine, 2022. nejm.org/doi/full/10.1056/NEJMoa2206038
  3. 3.NHS — Body mass index (BMI): about, categories and limitations. nhs.uk/health-assessment-tools/calculate-your-body-mass-index/

Weight-loss medicines are prescription-only. Suitability is always confirmed by a UK-registered prescriber.

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free consultation.

Three minutes of your time, reviewed by a UK-registered prescriber. No commitment, no charge for the consultation — and if treatment is approved, free next-day delivery to your door.

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