Lifespan: Why We Age and Why We Don't Have To

"This book is written by a genetics professor at Harvard who works in this area. It’s remarkable that a scientist has written such a personal book. It’s really about him and his research. What motivated him to get into the field was his grandmother who lived to 92, with the last decade of her life not being a good one. It’s a linear description of how we’ve made progress in understanding the process of aging. He is one of these people who thinks that a 200-, 300-, 400-year lifespan is possible, maybe even more than that. Of the five books, this is the one that gets inside the cell to explain what goes on inside ourselves as we age. That is devilishly hard to write about in a way that’s transparent, but he has a real gift for analogy. His particular view of aging is that it has to do with our genes not behaving properly and a gradual disorganization of the activities of the cell. There are things that can be done to fix that, and he’s really focused on one particular way of going about that, which is activating the protective molecules that our body has that are called ‘ sirtuins ’. The book is very much rooted in his own research, and he doesn’t hesitate to give health advice. But it’s perfectly reasonable advice—you know, eat a moderate amount, exercise, that kind of thing. “With laboratory animals, we’ve been able to make them live longer by about 20-25%. I think that’s a reasonable goal for humans” In terms of understanding the inner workings of aging, this is really an exceptional book. He talks about our DNA as being digital information, because there are these four letters that you have. Then there’s an analogue overlay, which is our epigenome. The analogy he makes is of a piano. It’s digital to a certain extent, you have a certain number of notes, and you can either be playing them or not. He talks about the epigenome as being the way that a pianist can play them softly, loudly or can emphasize them. That’s what goes wrong with aging. He describes it extremely well. He collaborated with a journalist, Matthew LaPlante, in writing it. I don’t know how much of the excellent writing is due to which person, but it is really well done. In the latter part of the book, he talks about the consequences. If we did all live 200 years, would that be a global calamity or not? He’s on the side of, ‘No, that’s a problem we can deal with. Overpopulation won’t be a problem. Social security systems will not go bankrupt.’ He’s an extreme optimist, I would say, who argues that all problems will be solved. He sees birth rates going down and down as people live longer and longer. That does seem to be true globally. The places with high birth rates are the places with low life expectancy and vice versa."