To achieve healthy weight loss, you must first find out your BMI - To work our your BMI or body mass index, you need your height and weight. Healty weight loss is necessary if you BMI is over 25 points. You hear a lot about BMI and it is a recognised measure of your weight. Your BMI is an indicator of your body mass and will tell if you need to gain or lose weight. It is important to maintain a healthy BMI or Body mass index. A BMI under 20 points is unhealthy and a BMI over 25 points is overweight. So, keep your BMI (Body mass Index) between 20 and 25. You can also find out your protein factor, which is the amount of protein your body needs on a daily basis to be healthy and maintain muscle mass. A personal coach will help you work out a meal plan, including lots of lean protein to maintain and build muscle mass and so increase your RMR (resting metabolic rate) and burn more fat.