If someone wants to smoke, that's their business, and they have every right to do so. But they must be aware of what they're doing to this beautiful gift they've been given, and they must be aware that as long as they smoke, they won't be living life to the fullest possible extent. The overweight person won't be able to climb the mountain and see the view from the mountaintop, nor will the drug user. The underweight person won't have nearly enough energy to do many of the things they'd be able to do if they ate a diet that was sufficient for their energy needs. You have a wonderful machine as a body that can do things that we don't even notice, but that make life a beautiful experience.
Healthy people have a stronger sense of self, and have higher self-esteem.
As a result, they treat others differently, and they face challenges with more confidence and hope for positive outcomes. You are a beautiful gift to the rest of us, and we want you to be happy and fulfilled, and we want you to be able to do whatever you wish to do, without the artificial restraints of an unhealthy body. The poorest man would not part with health for money, but the richest would gladly part with all his money for health. There are lots of people in this world who spend so much time watching their health that they haven't the time to enjoy it.