I can't explain it to you in concrete terms either. Perhaps the best way to put it is this: just as no one has a right to health, there is no obligation to live healthily. Not everything that could be unhealthy is harmful. Not everything that promotes good health is free of harmful effects. Each person must decide for themselves every day what they do, what it brings them and how much it might harm them. This assessment can only be made on an individual basis.