The Longevity Book: Live stronger. Live better. The art of ageing well.. Cameron Diaz

that they feel, overall, pretty damn young. This does not mean that we are immune from the subtle reminders of ageing. Our bodies start to communicate with us in new ways, and sometimes with different needs. I am well aware that the wiggle room I had when I was thirty-five will not be the same when I am forty-five. I try to be constantly in check with the daily choices that make up the equation of my well-being, noticing where there’s room for improvement or where I might have room to indulge a little bit more. These days I see and feel the impact of those choices, for better or worse, on my skin, my flesh and muscle, my energy, and my mood a lot more quickly than I used to. But I’ve still got a lot of energy, and strong muscles, and I work hard to keep those going. And I know that discipline and the strength it builds are the assets I will need if I want to age with health.

      I will continue to work hard because I know that this opportunity to live through the decades, let alone to keep learning and growing with the decades, is new. If forty was still the end of life instead of the beginning of a new phase, I would never have had the chance to experience marriage. I would be six feet under instead of planning the next forty years with the love of my life. I think it’s so sad that instead of applauding our birthdays, instead of appreciating them, instead of being grateful for this extra time, so many of us lie about our age. As women, we are routinely shamed for ageing. We are made to feel that getting older – and especially, looking older – is somehow a personal failure.

      When Sandra and I learned that 165 years ago, our sisters had one foot in the grave at forty – our age! – it changed the way we thought about our midlife. That fact that we can grow old enough to look old, in droves, is far from a failure. It happens to be the end product of arguably the biggest success story in human history.

      THE MIDLIFE CRISIS CELEBRATION

      In order to really appreciate why our midlife crises should actually be midlife celebrations, we need to take a step back and look at the whole of human history as well as our own personal and familial stories. Medicine has made some huge advances over the past century, and all our lives reflect those benefits. Many of us walking around today might not be alive had we been born a hundred years earlier – including me, and including Sandra.

      When I was only three months old, I woke up with a slight fever. My mother called the doctor, who said that she should continue to monitor me throughout the day. My temperature kept rising. By the middle of the day, my fever was so high she didn’t need the thermometer to know something was very wrong. She called my father to tell him to meet us at the hospital. Once we arrived, I was diagnosed and treated quickly. The A&E doctors gave me some medicine, my parents took me home, and I recovered within a few days. When Sandra was a child, her mother noticed that she had a strange rash: her body was covered with a smattering of tiny red dots. They rushed to the paediatrician, who diagnosed scarlet fever and gave her some antibiotics. A few days later, she was fine. It was our great luck to be born in an age when drugs like penicillin are easily obtained. But before modern medicine, children died regularly from fevers.

      And how about those less dramatic events, the daily occurrences we barely even notice? If I get a cut, I don’t think too much about it. I wash the wound with hydrogen peroxide, give it a consistent slathering of antibiotic cream, and it’s as good as new by the next weekend. But without those over-the-counter antibacterial and antibiotic helpers, life-threatening infection could set in. People used to die from scrapes, but you and I are confident that we’ll be just fine without having to give it another thought.

      We all have stories. Scraped knees. The bugs you caught from the neighbourhood kids. All those earaches and sore throats. Minor maladies, eased with a trip to the doctor. Our lives are routinely saved by pills and ointments and injections. But for most of human history, infections from cuts could lead to blood poisoning. Illnesses like pneumonia and strep throat, even diarrhoea, could be life threatening.

      Today, in the Western world, diseases that were a dire threat since people have been keeping written records have been virtually eradicated. Illnesses that killed kings and queens don’t trouble us at all. The tiny blip of history in which we are currently living is the only one in which fear of contracting smallpox doesn’t govern our daily activities. And the reason we are granted this good fortune is because regular people and doctors alike got curious about how we could live better, investigated their environments, and then applied what they learned so that we could all become healthier.

      That is why longevity is, in many ways, a modern phenomenon. The fascinating thing is that we have almost exactly the same DNA as the people who preceded us, but we get to live a lot longer. Genetically speaking, even in ancient Rome, a person who managed to get the right nutrition and get enough sleep and steer clear of diseases and wars and lions and gladiators could have made it all the way to a ripe old age. But the environment of ancient Rome made celebrating your eightieth birthday a pretty impossible goal to achieve. And, in fact, so did most environments of most places, until the twentieth century.

      TRIGGERING IMMUNITY

      For millennia, smallpox was public enemy number one. It was recorded in the ancient medical literature of Persia, India, and China and has been noted on the remains of Egyptian mummies. Smallpox is even thought to have contributed to the first decline of the Roman Empire. When the Crusaders marched over the continent, smallpox marched home with them. And later, when Europe caught discovery fever and sent explorers and emissaries sailing over the seas to the new lands to the West, smallpox hitched a ride.

      In England and in the new American colonies, the death toll was enormous. A bad case of smallpox meant a 60 per cent chance of death. By the eighteenth century in England, 400,000 people a year were dying of smallpox, and there was no cure in sight.

      But in countries like China, Turkey, and Africa – which had been suffering the ravages of smallpox for eons – a traditional “folk” treatment was helping to stem the tide. In China, a process called inoculation had developed as early as 1100, when it was observed that those who survived smallpox became resistant to the disease. Healers began inserting smallpox-infected needles into otherwise healthy people to deliberately make them sick. This treatment not only helped people survive their case of smallpox, but granted them immunity from future exposure.

      Turkish tradesmen had attempted to tell the Europeans about this process, but in England, they weren’t buying it. Variolation needed a champion in order to be accepted by Western medicine, and it found one in a woman named Lady Mary Montagu, the wife of England’s ambassador to Turkey.

      In 1715, Lady Montagu travelled with her husband to Constantinople, and her visit changed the world. In Turkey, Lady Montagu learned about the local method of managing smallpox.

      “There is a set of old women who make it their business to perform the operation every autumn”, she wrote. “The old woman comes with a nut-shell full of the matter of the best sort of smallpox, and asks what veins you please to have opened … She immediately rips open that you offer her with a large needle … and puts into the vein as much venom as can lie upon the head of her needle.”

      Lady Montagu had an intimate relationship with smallpox. It had killed her brother, and it had left her face badly scarred, a daily reminder of what could happen to her children if they contracted the disease. She wanted to do whatever she could to protect them.

      First, she had her young son inoculated by the embassy doctor. Then she brought the procedure back to England and had the same physician inoculate her young daughter in front of an audience of court doctors. Eventually the procedure became widely accepted – a precursor to our modern-day vaccinations.

      FIGHTING AN INVISIBLE ENEMY

      The first breakthrough in extending the human life span was learning to recognize what was invisible: the microbes