1. What is the NHS Weight Loss Calculator?

The NHS Weight Loss Calculator estimates potential weight loss based on your daily caloric deficit and the duration of your diet. It uses the scientifically validated principle that a deficit of 7700 kcal equals approximately 1 kg of weight loss.

2. How Does the Calculator Work?

The calculator uses the weight loss formula:

Where:

• \( deficit \) — Daily caloric deficit (kcal/day)
• \( days \) — Duration of diet (days)
• \( 7700 \) — Estimated kcal needed to lose 1 kg of body weight

Explanation: The formula calculates how much weight you can expect to lose based on your sustained caloric deficit over time.

3. Importance of Caloric Deficit

Details: Creating a consistent caloric deficit is the fundamental principle behind weight loss. This calculator helps you understand the relationship between your daily deficit and expected weight loss over time.

4. Using the Calculator

Tips: Enter your average daily caloric deficit (difference between calories consumed and calories burned) and the number of days you plan to maintain this deficit. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Is the 7700 kcal/kg rule accurate for everyone?
A: While generally accurate, individual results may vary due to metabolic adaptations, body composition changes, and other factors.

Q2: What's a safe daily caloric deficit?
A: NHS recommends a deficit of 500-600 kcal/day for safe, sustainable weight loss of about 0.5 kg per week.

Q3: Why might my actual weight loss differ?
A: Water retention, muscle gain, metabolic changes, and inaccurate calorie tracking can all affect actual results.

Q4: Can I use this for weight gain calculations?
A: Yes, by entering a caloric surplus instead of deficit, though muscle/fat gain ratios differ from pure fat loss.

Q5: How should I combine this with exercise?
A: Include exercise calories in your total deficit calculation for more accurate predictions.