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
Is Actimel Good For Weight Loss?
Actimel is a probiotic yogurt drink marketed for digestive health, but it's not designed as a weight loss product. While a healthy gut may support overall wellness, Actimel alone won't help you lose weight — weight management requires a calorie deficit, physical activity, and sometimes prescription weight loss medication. If you're interested in evidence-based weight management in the UK, our free BMI calculator can help you understand your starting point, and we'll cover what actually works for sustainable weight loss below.
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.
What is Actimel and Can It Help With Weight Loss?
Actimel is a fermented milk drink containing L. casei bacteria, promoted as a gut health supplement. Each small bottle contains approximately 100 calories and is marketed to support digestive function. However, there's no robust clinical evidence that Actimel specifically aids weight loss. In fact, regular consumption adds extra calories to your diet — unless you replace other foods with it, it will likely contribute to weight gain rather than loss.
Weight loss in the UK is achieved through:
- Creating a calorie deficit (consuming fewer calories than you expend)
- Increasing physical activity and building muscle
- Making sustainable dietary changes aligned with NHS guidance
- In some cases, prescription weight loss medication prescribed after clinical assessment
While probiotics may have minor roles in gut health, they are not a weight loss tool. If you're managing your weight, focus on these proven methods rather than relying on any single food or drink product.
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.
Effective Weight Management: What the Evidence Actually Supports
The NHS recommends sustainable weight loss of 0.5 to 1 kg per week, achieved through a combination of reduced-calorie diet and increased physical activity. For adults with a BMI of 30 or above, or 25–29.9 with weight-related health conditions, prescription weight loss medication may be considered as part of a comprehensive weight management plan.
These evidence-based approaches include GLP-1 weight loss injections like Mounjaro and Wegovy, which work alongside lifestyle changes — not as replacements for them. Try our free GLP-1 weight loss calculator to explore potential outcomes with evidence-based treatment options. Remember, individual results vary significantly, and any prescription medication requires assessment by a licensed prescriber.
- 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.
Does drinking Actimel help you lose weight?
No. Actimel is a probiotic yogurt drink with approximately 100 calories per bottle. Consuming it regularly adds calories to your diet unless you replace other foods. Weight loss requires a calorie deficit, which Actimel does not create. While gut health is important, Actimel alone is not a weight loss product.
What actually works for weight loss in the UK?
Evidence-based approaches include creating a calorie deficit through diet and physical activity, following NHS-aligned eating patterns like the Mediterranean diet, and in some cases, prescription weight loss medication. Sustainable weight loss is typically 0.5–1 kg per week. Use our free BMI calculator to assess your starting point and discuss options with your GP.
Can probiotics help with weight management?
Some research suggests a healthy gut microbiome supports overall health, but probiotics alone do not cause weight loss. Any weight loss benefit is indirect — from improved digestion supporting better food choices. They should never replace core weight management strategies like calorie deficit and physical activity.
Are there prescription weight loss options available in the UK?
Yes. Adults with a BMI of 30 or above, or 27–29.9 with weight-related health conditions, may be eligible for prescription weight loss medications like Mounjaro or Wegovy. These are GLP-1 medications that require clinical assessment. Access is available through NHS specialist services or private online prescribing.
How do I track my weight loss progress?
Use our free progress tracker to log your weight, measurements, and notes over time. Set realistic goals (0.5–1 kg per week), measure weekly, and remember that progress isn't always linear. Also use our free BMI calculator regularly to see how your BMI shifts as you progress toward a healthier weight range.
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.