Why We Die

Venki Ramakrishnan presents an engaging and accessible exploration of the science behind ageing, offering a clear and insightful look at how our understanding of the field has evolved. He provides a candid account of the scientists, debates, and missteps that have shaped ageing research, skillfully guiding readers through the discoveries and false leads that have broadened our knowledge.

A highlight of the book is how Ramakrishnan seamlessly weaves together the story of scientific progress with personal insights into the lives of researchers. Remarkably, despite his own Nobel Prize1, Ramakrishnan is pleasingly humble. He generously credits other scientists, such as Alfred Russel Wallace alongside Charles Darwin, for the theory of evolution, noting how Wallace's observations finally spurred Darwin to publish his ground-breaking work.

Though some technical details may challenge readers without a strong background in biology, Ramakrishnan's writing makes complex ideas easy to grasp. He uses relatable metaphors, comparing DNA to an anthology of instruction booklets for assembling proteins while explaining the intricate process of DNA replication that allows life to flourish.

One critical insight Ramakrishnan highlights is the delicate nature of DNA replication, which is prone to errors. He explains how much of a cell's energy is spent repairing these mistakes, with genes like p53, often called "The guardian of the genome," playing a crucial role. Faulty p53 genes, linked to many cancers, underscore

1 Venki Ramakrishnan, a British-American structural biologist, was awarded the Nobel Prize in Chemistry in 2009, alongside Thomas A. Steitz and Ada Yonath, for his pioneering work on the structure and function of the ribosome. His research, which utilized X-ray crystallography, was instrumental in revealing the ribosome’s atomic structure, providing critical insights into how ribosomes translate genetic information into proteins.

the delicate balance between preventing cancer and accumulating cellular damage— a trade-off that drives the ageing process.

Ramakrishnan also delves into telomere shortening, where protective ends of DNA become shorter with each cell division, limiting how many times cells can divide before essential genetic information is lost. He points out the connection between stress and ageing, explaining how the stress hormone cortisol accelerates this telomere shortening.

A fascinating aspect of the book is Ramakrishnan's discussion of cell reprogramming. He highlights Shinya Yamanaka's discovery of how specialized cells can be reverted to a more versatile, pluripotent state by removing epigenetic markers. This breakthrough in regenerative medicine offers the potential for reversing some effects of ageing or repairing injuries. Ramakrishnan also explores the impact of prenatal conditions on gene expression. For example, children born to mothers who experienced famine during pregnancy show higher rates of health problems, illustrating how external factors can influence gene activity without altering DNA— reminiscent of Lamarckian inheritance, where traits acquired during life are passed down to offspring.

Throughout the book, Ramakrishnan provides rich scientific insights into ageing, portraying it as the gradual accumulation of cellular dysfunction—damaged mitochondria, malfunctioning proteins, and senescent cells. He also explains why cancers appear later in life, as the body's defences against cancer weaken over time. Toward the end, Ramakrishnan offers practical advice on extending lifespan, noting that caloric restriction and exercise can reduce the build-up of damaged proteins and promote healthier cellular function. He even touches on the intriguing albeit unsettling idea of "young blood" transfusions, which have shown some potential for rejuvenating older animals, though more research is needed.

In the book's final chapter, Ramakrishnan tackles the ethical dilemmas of ageing research. As biotech advances closer to extending human life, questions arise about the societal impact of a growing ageing population. The involvement of wealthy investors in pursuing personal immortality adds complexity, as their interests could drive the field in unpredictable and socially disruptive directions.

Although the author strives to make complex ideas accessible, a basic understanding of cell biology and DNA replication will help readers avoid feeling overwhelmed by the information. The book presents a clear timeline of scientific breakthroughs in ageing and mortality, examining the efforts of those seeking to cheat death and considering the ethical dilemmas these pursuits raise. It's a thoughtprovoking work that may require multiple readings to uncover deeper insights. While Ramakrishnan remains grounded about the challenges of reversing ageing, he emphasizes the need to consider these advancements' ethical and societal implications.

In the meantime, his advice is straightforward: imbibe a frugal and balanced diet with exercise and stay informed on the evolving science of ageing. Exercise and sleep significantly impact several critical factors related to ageing, such as insulin sensitivity, muscle mass, mitochondrial function, blood pressure, stress management, and the risk of dementia. These natural interventions are, at present, more effective than any anti-ageing medications on the market, incur no cost, and have no adverse side effects.

Venki notes, "A greatly extended life span would deprive our lives of urgency and meaning, a desire to make each day count. It is not clear that even with an entire extra lifetime, we are accomplishing more than the great writers, composers, artists, and scientists of past eras. We may live a very long life bored and lacking in purpose. It could also lead to a stagnant society since many of the big social changes have been spearheaded by younger generations. Still, if someone were to offer a pill that would add ten years of healthy life, hardly anyone would decline it".