Can you please explain why being healthy is important in life?

Your body & mind: Your body and mind are both important parts of you to keep healthy, so that you can do what you want to do in the world & in life. Otherwise you could be limited, and enjoy life less than you otherwise would. If you're mentally unhealthy, and addicted to drugs/alcohol, etc this also impacts people you care about & who care about you. Physical illness hurts; mental illness skews perception itself.

Let's think: My personal definition of health is having a mind and body that lets me work, play, and love others as i want. These are important to me & i bet to you. Try to maintain your health so you can keep doing stuff you enjoy and find meaningful. One of my colleagues is blind and paralyzed from the neck down after a stupid suicide attempt. We could ask him your question. Choose a good life for yourself.