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
Low Carb Weight Loss — What Works in the UK
Low carbohydrate diets are popular for weight loss, and evidence suggests they can be effective in the short term. A low carb approach typically means reducing intake of bread, pasta, rice, and sugary foods, while eating more protein and healthy fats. However, long-term weight loss success depends on finding an eating pattern you can sustain. The NHS recommends losing weight at a rate of 0.5 to 1 kg per week, and any diet should be combined with increased physical activity. Whether low carb is right for you depends on your individual health, preferences, and whether you can stick with it long-term.
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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 Low Carb Diets Support Weight Loss
Low carbohydrate diets work by reducing carbs, which naturally reduces overall calorie intake for many people. Carbohydrates are broken down into glucose, which triggers insulin release. When carbs are restricted, insulin levels drop, potentially reducing hunger and food cravings. Additionally, protein and fat are more satiating — they help you feel fuller after meals and for longer periods.
In weight management across the UK, low carb approaches have shown promise for both short-term and moderate long-term weight loss. Clinical evidence suggests that a low carb diet produces similar long-term results to calorie-restricted diets when sustained — meaning the total calorie deficit is what matters most. Some people find low carb easier to follow because reduced hunger makes maintaining a calorie deficit more manageable. Try our free weight converter to track your progress in kg, stone, and lbs as you work towards your goal. Our BMI calculator can also help you understand your current weight category and set a realistic healthy weight target.
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.
Low Carb vs Other Weight Loss Methods
Low carb diets are one of several approaches to weight management in the UK. Compared to balanced, moderate calorie restriction, low carb tends to produce faster initial weight loss — but much of this is water loss, not fat loss. NHS weight loss guidance emphasises sustainable approaches: a reduction of 500 kcal per day typically results in approximately 0.5 kg weekly loss.
For some people, low carb fits their lifestyle and preferences, making adherence easier. For others, a Mediterranean-style diet or moderate calorie reduction works better. If you're considering prescription weight loss medication like GLP-1 injections for weight management UK, these are prescribed alongside dietary changes — not instead of them. Use our GLP-1 weight loss calculator to explore how medication might support your goals, and our progress tracker to monitor your weight loss journey over time.
- 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.
Is a low carb diet safe for long-term weight loss?
Low carb diets are safe for most adults when well-planned and varied. However, very low carb (under 50g daily) long-term may need GP monitoring. The NHS recommends consulting your GP before starting any restrictive diet, especially if you have diabetes or take medication. A balanced approach with adequate protein, healthy fats, and some carbs is usually most sustainable.
How much weight can I expect to lose on a low carb diet?
Weight loss varies by individual, calorie deficit, and adherence. Initial loss is often 1–2 kg per week due to water loss. Long-term, expect 0.5–1 kg weekly with a 500 kcal daily deficit. The NHS recommends this steady rate. Use our BMI calculator to set a realistic healthy weight range for your height, then calculate your calorie needs with your GP.
Can I combine low carb diet with weight loss injections?
Yes. GLP-1 injections like Mounjaro and Wegovy are prescribed alongside dietary changes and physical activity — not as an alternative. A low carb diet combined with a GLP-1 injection may support greater weight loss for some people. Our GLP-1 weight loss calculator can estimate potential results. Always discuss medication with your prescriber alongside any diet plan.
What are good low carb foods for UK weight loss?
Eggs, fish, lean meat, Greek yoghurt, cheese, nuts, seeds, non-starchy vegetables (broccoli, spinach, peppers), avocados, and olive oil. Keep wholegrain options like oats in moderation rather than eliminating carbs entirely. A balanced low carb approach is more sustainable than extreme restriction and easier to maintain long-term.
How do I know if low carb weight loss is working?
Track progress with regular weigh-ins (weekly, same time of day). Use our weight converter to record in your preferred unit — kg, stone, or lbs. Our free progress tracker helps you spot trends over weeks, not just daily fluctuations. Also monitor how you feel — energy, mood, hunger levels. Aim for 0.5–1 kg per week. If progress stalls after 4–6 weeks, review calorie intake or consult your GP.
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.