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
Which Protein Shake Is Best For Weight Loss?
The best protein shake for weight loss depends on your personal preferences, dietary needs, and how it fits into your overall calorie intake. Protein shakes can support weight management in the UK when used as part of a reduced-calorie diet, but they're not a weight loss solution on their own. The key is choosing a shake with adequate protein, minimal added sugar, and reasonable calories — and using it alongside increased physical activity and a structured approach to weight management nhs guidance recommends. Whether you're considering protein shakes or exploring other weight loss options, understanding how they work is essential.
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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.
What Makes A Good Protein Shake For Weight Loss
A good protein shake for weight loss should contain at least 15–25g of protein per serving to support muscle retention and satiety during a calorie deficit. The shake should be low in added sugar — ideally under 5g per serving — to avoid unnecessary calories. Total calories should typically be 150–250 kcal per shake, depending on your daily calorie target and how you're using it (replacement meal vs. snack).
- Whey protein isolate: Fast-absorbing, complete amino acid profile, good satiety
- Plant-based blends: Suitable for vegans, though often require more volume for equivalent protein
- Casein: Slower-digesting, longer-lasting fullness effect
- Collagen or bone broth: Lower protein content, better suited as supplements rather than meal replacements
The NHS recommends that sustainable weight loss involves a calorie deficit of around 500 kcal per day, typically resulting in a loss of 0.5–1 kg per week. A protein shake can help you stay within this deficit by providing a convenient, portion-controlled option that reduces hunger between meals.
Clinically BackedWeight Loss
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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.
How Protein Shakes Fit Into Weight Loss Strategy
Protein shakes work best as part of a structured approach to weight loss medication nhs services also support — whether through lifestyle changes alone or combined with prescription options. Using our free GLP-1 weight loss calculator can help you understand your calorie needs and how protein shakes might fit into your daily plan. The most effective use is replacing one meal (typically breakfast or lunch) with a shake, rather than adding a shake on top of your normal diet.
Important: Protein shakes alone won't create the weight loss you're hoping for. They're a tool within a broader strategy that includes regular physical activity, balanced meals, and consistent calorie tracking. For personalised guidance on protein intake and weight loss strategy, consult your GP or a registered dietitian. If you're interested in prescription weight loss options, your GP can refer you to specialist weight management services.
- 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.
Are protein shakes good for weight loss?
Protein shakes can support weight loss when used as part of a reduced-calorie diet. They help maintain muscle mass, increase satiety, and provide a convenient low-calorie option. However, they're a tool within a broader strategy — not a standalone solution. Success depends on creating a calorie deficit and combining shakes with physical activity and healthy eating habits.
How many calories should a weight loss protein shake have?
A good weight loss protein shake should contain 150–250 calories, with at least 15–25g of protein and less than 5g added sugar. This calorie range makes it suitable as a meal replacement or substantial snack without derailing a calorie deficit. Your personal needs depend on your daily calorie target — use our BMI calculator to understand your baseline health metrics.
Is whey or plant-based protein better for weight loss?
Both whey and plant-based protein can support weight loss effectively. Whey protein is faster-absorbing and typically provides more protein per serving. Plant-based options work well too, though you may need a larger volume to match whey's protein content. Choose based on your dietary preferences and how the shake makes you feel.
Can protein shakes replace meals for weight loss?
Yes, a high-protein shake can replace one meal daily as part of a structured weight loss plan. However, you should still eat at least two balanced meals daily to ensure adequate nutrition. Replacing meals long-term without professional guidance isn't recommended — speak to your GP or a dietitian before making significant dietary changes.
How do protein shakes compare to prescription weight loss medication?
Protein shakes are a nutritional tool, while prescription medications like GLP-1 injections work through different mechanisms to reduce appetite and support weight loss. They're not mutually exclusive — some people use both together as part of a comprehensive weight management plan. Prescription options require clinical assessment from your GP, whilst shakes are available over-the-counter.
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.