Body weight is an outcome of ongoing lifestyle that includes long term changes of what you eat and how much you do, in term of physical activity. In other words, it is about balancing the calories you eat and calories you use to move your body.
Why it's important to monitor body weight?
Excessive fat in the body could increase risk of chronic diseases e.g. type 2 diabetes, hypertension, heart disease and certain type of cancers. On the other hand, underweight is also unhealthy as it may cause health problem such as anemia and low bone mass.