Well as humans we are living longer than we ever have before. As we get older we are more likely to damage our bodies or develop certain types of diseases. As we live for longer this means that we live a larger proportion of our lives when we may have damaged our bodies or have developed diseases. What we are trying to do is come up with ways to make sure that we can make the most of all stages of our lives. Hopefully that means that we will be healthy for longer and if we do damaged our bodies or get diseases then it is possible to help our bodies continue to function.