A Healthy Lifestyle is a GCSE maths enrichment booklet that uses real NHS and British Heart Foundation guidelines - calorie allowances, the BMI formula, step targets, sleep recommendations, and heart rate zones - to teach six genuinely different areas of GCSE maths, from percentages and algebra to averages, ratio, and probability. Each of its six chapters pairs a worked example with practice exercises grounded in everyday health scenarios, closing with a mini project and full answer key.