People naturally come in different shapes and sizes, and there is a range of weight which is believed to be healthy. Body mass index (BMI) is one way to work out if you're a healthy size. It's calculated by dividing your weight in kilograms by your height in metres, squared.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/how-to-lose-weight-in-a-healthy-way