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
Does Sex Help Weight Loss?
Yes, sex can contribute to weight loss as a form of physical activity, though the amount of calories burned varies significantly between individuals. Sexual activity is moderate-intensity exercise that increases heart rate and engages multiple muscle groups. However, sex alone is unlikely to create the substantial calorie deficit needed for meaningful weight loss. For effective weight management in the UK, sex works best as part of a broader approach combining regular exercise, balanced nutrition, and where appropriate, medical support like prescription weight loss medication.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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 Much Calories Does Sex Burn?
Research suggests that sexual activity burns approximately 3–5 calories per minute on average, though this varies based on factors like duration, intensity, body weight, and individual metabolism. A 30-minute session might burn roughly 90–150 calories — equivalent to a light walk or gentle exercise session. For context, the NHS recommends a calorie deficit of around 500 kcal per day to lose approximately 0.5 kg per week. To rely solely on sex for weight loss would require unrealistic frequency or intensity. The most effective weight management in the UK combines regular cardiovascular exercise (like brisk walking or cycling), strength training, balanced nutrition, and where clinically appropriate, prescription weight loss medication. Our free GLP-1 weight loss calculator can help you understand realistic projections when combining lifestyle changes with medical support if eligible.
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.
Sex as Part of a Complete Weight Loss Strategy
Sex should be viewed as one component of overall physical activity, not a primary weight loss tool. The NHS emphasises that sustainable weight loss requires consistent calorie deficit, regular movement, and healthy eating habits. For adults seeking weight management support in the UK, evidence-based approaches include a reduced-calorie diet (typically 500 kcal below maintenance), at least 150 minutes of moderate-intensity aerobic activity weekly, and strength training twice weekly. If you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions like type 2 diabetes or hypertension, prescription weight loss medication may be appropriate following clinical assessment. Try our free BMI calculator above to understand your current health category, and discuss comprehensive weight management options with your GP.
- 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.
How many calories does 30 minutes of sex burn?
Research suggests approximately 90–150 calories depending on intensity, body weight, and individual metabolism. This is equivalent to a light walk. However, this modest calorie burn is only effective for weight loss when combined with consistent diet and exercise habits. Sex alone cannot create the sustained calorie deficit needed for meaningful weight loss.
Is sex better for weight loss than other exercise?
No. Sex burns fewer calories than dedicated cardiovascular exercise. A 30-minute brisk walk typically burns 150–250 calories, and gym sessions can burn significantly more. Sex should complement, not replace, structured exercise as part of a weight management plan.
Can sex help with weight loss medication like Mounjaro or Wegovy?
Sex is a form of physical activity that may support overall fitness. Prescription weight loss medications like Mounjaro (tirzepatide) and Wegovy (semaglutide) work best alongside increased physical activity and reduced-calorie diet. All three factors together support better outcomes than any one alone.
What's the best approach to weight loss in the UK?
The NHS recommends combining a calorie deficit (roughly 500 kcal/day for 0.5 kg weekly loss), 150 minutes of moderate aerobic activity weekly, strength training, and balanced nutrition. For eligible adults, prescription weight loss medication following GP assessment can significantly enhance results.
How do I know if I need professional weight loss support?
If you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions (diabetes, hypertension, sleep apnoea), contact your GP about NHS weight management services or specialist assessment. Use our free BMI calculator to check your current category first.
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.