The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
Free tracker included with every download this week
What Foods Can You Eat On Mounjaro?
When taking Mounjaro (tirzepatide), there are no forbidden foods — but your appetite and food preferences typically change significantly. The injection doesn't restrict what you can eat; instead, it reduces hunger and cravings, making smaller portions satisfying. Most people find they naturally eat less and prefer different foods than before starting treatment. Your GP or prescriber can give you personalised dietary advice, but understanding how Mounjaro affects appetite helps you make informed food choices throughout your treatment.
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Calculate Your BMI Instantly
Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
How Mounjaro Changes Your Relationship With Food
Mounjaro works as a dual GIP and GLP-1 receptor agonist, which means it activates two natural hormone pathways that regulate appetite and fullness. This typically results in significantly reduced hunger, decreased cravings for high-calorie foods, and earlier satiety — you feel full after eating much smaller amounts than before.
Most people on Mounjaro report:
- Reduced appetite, especially in the first 4–8 weeks after starting
- Less interest in foods they previously craved (particularly sugary, fatty, or processed foods)
- Increased preference for protein-rich foods and vegetables
- Nausea and taste changes, particularly in the first few weeks (a very common side effect)
- Better satisfaction from smaller portion sizes
Because of these changes, you don't need to follow a strict diet plan. Instead, focusing on nutrient-dense foods alongside a reduced-calorie diet helps you get maximum nutrition from smaller meals. This is why Mounjaro works best when combined with lifestyle changes, not instead of them.
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
Best Foods To Eat While On Mounjaro
While there are no forbidden foods on Mounjaro, prioritising protein, vegetables, whole grains, and healthy fats helps you feel fuller longer and supports sustainable weight loss. Lean proteins like chicken, fish, eggs, and Greek yoghurt are particularly satiating. Vegetables — especially leafy greens, broccoli, and peppers — are low-calorie and nutrient-rich.
Foods to approach with caution include very sugary items, deep-fried foods, and high-fat processed foods — not because they're forbidden, but because they may cause nausea or discomfort while on Mounjaro, especially during dose titration. Many people find these foods simply unappealing once the medication takes effect. Small, regular meals work better than large meals, as Mounjaro slows gastric emptying. Staying hydrated and taking your time with meals is important.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
Can I eat normally while taking Mounjaro?
You can eat most foods, but Mounjaro significantly reduces appetite and changes food preferences. Most people find they eat much smaller portions naturally and feel satisfied sooner. There's no strict "Mounjaro diet" — focus on balanced, nutrient-dense meals and listen to your body's hunger signals, which will be noticeably different than before.
Will Mounjaro make me feel sick when I eat?
Nausea is very common, especially in the first 4–8 weeks and when increasing doses. Eating smaller, more frequent meals, avoiding fatty or greasy foods, and eating slowly can help reduce nausea. If nausea is severe or persistent, contact your GP — your prescriber may adjust your dose or offer additional support.
Should I follow a specific diet while on Mounjaro?
No specific "Mounjaro diet" is required, but combining the injection with a reduced-calorie diet and increased physical activity gives the best results. Clinical trials showed weight loss worked best alongside lifestyle changes. Your GP can refer you to a dietitian for personalised guidance if needed.
What happens if I eat sugary or fatty foods on Mounjaro?
Eating sugary or fatty foods isn't forbidden, but many people find these foods unappealing once Mounjaro takes effect. Some experience nausea or stomach discomfort after eating high-fat foods. Most people naturally gravitate toward lighter, protein-rich options because they feel more satisfying.
How does Mounjaro compare to Wegovy for food choices?
Both Mounjaro and Wegovy reduce appetite and affect food preferences similarly — Mounjaro uses a dual GIP and GLP-1 mechanism while Wegovy (semaglutide) uses GLP-1 only. Both allow all foods but typically reduce cravings. Individual responses vary, and your prescriber can advise which may suit you better based on your health profile.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.