Over this period average life expectancy in all countries in the world has risen from about 40 years or less to around 80 years of life. Many more people are living to very old ages. Around 120 years of life seems to be the very maximum potential lifespan.
The book is aimed at an interested reader who may not have a grounding in scientific investigation or the biological science. I therefore start by looking at the nature of evidence and the way that scientific research has increased our knowledge of the human body. I look at the ways that lifestyle can drastically shorten lifespan and take a look at those factors that may increase duration of life. This encompasses diet, obesity, smoking, exercise and genetics. We live in unprecedented times with an enormous expansion in global population.
Within my lifetime the structure of DNA was described, the human genome decoded, stem cells discovered and computers invented. In the second half of the book I go on to describe how these and other discoveries have the potential to increase the human lifespan well beyond anything that has been achievable in the past.
