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
1400 Calories a Day for Weight Loss: What You Need to Know
A 1400-calorie daily diet is a moderate restriction that may support weight loss for some UK adults, though individual needs vary considerably. The NHS recommends a calorie deficit of around 500 kcal per day to achieve sustainable weight loss of approximately 0.5 to 1 kg per week. Whether 1400 calories is appropriate depends on your current weight, activity level, age, and metabolism. This guide explains how this calorie level works, who it may suit, and how to approach it safely alongside other weight management approaches.
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.
Is 1400 Calories a Day Safe for Weight Loss?
A 1400-calorie daily intake is generally considered moderately restrictive for most UK adults. The NHS advises that very low-calorie diets (under 800 kcal per day) should only be followed under medical supervision, so 1400 calories falls in a safer range for self-directed dieting.
However, whether 1400 calories is appropriate for you depends on:
- Your current weight: Larger individuals have higher baseline calorie needs; 1400 may represent a smaller deficit for them
- Your activity level: Sedentary individuals may feel hunger and fatigue at this level; active people may adjust more easily
- Your age and sex: Younger, larger, or male individuals typically have higher baseline calorie requirements
- Your metabolism: Individual metabolic rates vary by 10–25% due to genetics, medication, and health conditions
Use our free BMI calculator above to understand your current weight status, then discuss a personalised calorie target with your GP or a registered dietitian. They can assess whether 1400 calories suits your individual health profile and goals.
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.
Expected Weight Loss at 1400 Calories Per Day
If 1400 calories represents a 500 kcal deficit for you, you could expect to lose approximately 0.5 kg (1 lb) per week — the NHS-recommended safe rate. Over 12 weeks, this would total roughly 6 kg of weight loss.
However, weight loss is not linear. Initial loss in the first 1–2 weeks often includes water weight and may feel faster. After that, loss typically settles to a steadier 0.5–1 kg per week. To track your actual progress, use our free progress tracker to log your weight weekly and identify your real loss pattern rather than relying on estimates.
For sustainable results, combine any calorie reduction with increased physical activity and behaviour change. If you're interested in weight management support from prescription medications like GLP-1 weight loss injections, try our GLP-1 weight loss calculator to explore how medical support might complement your dietary efforts.
- 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 1400 calories a day too low?
For most UK adults, 1400 calories is not dangerously low, but it is moderately restrictive. The NHS classifies diets under 800 kcal as very low-calorie diets requiring medical supervision. At 1400 calories, you should monitor energy levels, hunger, and mood. If you feel unwell, consult your GP. A registered dietitian can personalise this for your needs.
Will I lose weight on 1400 calories a day?
Yes, if 1400 calories creates a deficit for you. Most UK adults would see weight loss at this level, typically 0.5–1 kg per week if the deficit is around 500 kcal. However, individual results vary based on current weight, metabolism, activity, and adherence. Our free weight loss calculator can help estimate potential loss with medical support.
How does 1400 calories compare to NHS weight loss guidance?
The NHS recommends losing weight at 0.5–1 kg per week, achieved through a calorie deficit of around 500 kcal per day. For many people, this means eating 1200–1800 calories depending on baseline needs. 1400 calories often fits within this range, but NHS advice emphasises personalisation — your GP can recommend the right deficit for you.
Can I combine 1400 calories with weight loss medication?
Yes. Prescription weight management medications like Mounjaro and Wegovy work best alongside reduced-calorie intake and increased physical activity. These GLP-1 medications may help reduce hunger and appetite, making calorie reduction more manageable. A prescriber will assess whether medication suits your health profile.
Should I see my GP before starting a 1400-calorie diet?
Yes. Before making significant dietary changes, discuss your plans with your GP, especially if you have any health conditions, take medications, or are trying to manage a condition like type 2 diabetes. Your GP or a registered dietitian can personalise your calorie target and ensure weight loss approaches are safe and sustainable for your individual circumstances.
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.