All of us would like to live longer, or to slow the debilitating effects of age. Coleen Murphy, a leading scholar of aging,  show how recent research on longevity and aging may be bringing us closer to this goal. She explains that the study of model systems, particularly simple invertebrate animals, combined with breakthroughs in genomic methods have allowed scientist to probe into molecular mechanisms of longevity and aging. Understanding the fundamental biological rules that govern aging in model systems provide clues about how we  might slow human aging, which could lead in turn to new therapeutics and treatments for age-related disease.

Murphy describes her research that shows how changing a single gene in the nematode worm C, elegant doubles its lifespan, extending not only the end of life but also the youthful, healthy part of life. Drawing on work in her own lab as well as other recent research, Murphy chronicles the history and current state of the field, explaining longevity’s links to reproduction and mating, sensory and cognitive function, inheritances from our ancestors and the gut microbiome. Written with clarity and wit, How We Age provides an essential guide to the science what we know about aging, how we know what we know, and what we can do with this new knowledge.

Biologist Matt Kaeberlein breaks down the science of longevity and tell us how he is using a robot to test 100, 000 aging interventions a year on microscopic worms and a long-term study on the aging of pet dogs. This hasn’t stopped the quest for the perfect life-extending herb or routine, as everything from red wine to fish oil has been purported to help you live just a little longer.

Murphy and Ramakrishnan provide fascinating accounts of the importance of work with yeast, fruit flies and mice. These species’ short life  cycles  -40-50 days in the case of fruit flies- allow experiments that would simply not be possible with humans.  Much of Murphy’s own research has been with the tiny nematode worm c elegans, which possess only 959 cells  by comparison we have more than 50 trillion. She explains how the discovery in 1993 that a mutation in a single gene could double the worm’s lifespan gave new hope and credibility to anti-ageing research.

One intervention in particular has been shown repeatedly to work across species: Caloric restriction, which can slow ageing and the onset of age-related diseases  by 10 to 30 per cent  in flies, mice and even monkeys. Scientists are  racing to uncover exactly why caloric restriction promotes longevity, in the hope that the effects can be replicated without needing to live in a state of grouchy semi-starvation. One compound in particular is showing promise in mimicking CR: rapamycin,  named after Rapa Nui (Easter Island) where it was first found.  Ramakrishnan discovered the small but powerful molecule, a product of soil bacteria that was first developed for its antifungal properties. Rapamycin seems to flick the same protein switches as caloric restriction, but without the depressing diet. But rapamycin is immunosuppressant, as long term use could increase the risk of infection. The economic of living longer, healthier live is potentially huge, with lower health and care costs and greater productivity.

How We Age: The Science of Longevity by Coleen Murphy, Princeton University Press, £22, 464 pages.