That is a strange question that you were asked. I think life, as a whole, is always and will always be a learning and growing experience. Even the "not good for you" things lend to knowledge and education, so why not try to ensure that growth is positive?
You are doing a great job. Don't listen to that strange comment from your friend.
People seem to like passivity, but want the results of being active. This is why the solution to being over weight is a pill or surgery, not watching diet and exercising.