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Methuselah’s mixture

			associated with a low-level, chronic
			inflammation of many of the body’s
			tissues, for instance. Insulin, a
			hormone that regulates the
			metabolism of glucose, also crops
			up.
		5	Most intriguing of all is something
			that scientists have known for
			decades: feeding near-starvation
			diets to laboratory animals such as
			mice and fruit flies can extend their
	Anti-ageing research		lifespans by 40% or more, and
			improve health along the way. If
	Methuselah’s mixture		those results translated directly to
	Methuselah’s mixture		humans (and there is some
	The Youth Pill:		preliminary evidence that fasting may
	Scientists at the Brink of		confer benefits in people), then the
	an Anti-Ageing Revolution.		human lifespan could reach 150
	By David Stipp.		years. Many explanations have been
			offered and discarded. Production of
1	FOR as long as people have been		the harmful chemicals that are a
	growing old, they’ve been wishing		side-effect of respiration, might be
	they didn’t have to. The “Epic of		reduced, for instance, or there might
	Gilgamesh”, one of the most ancient		be a lowering of blood-sugar levels,
	works of literature, chronicles the		which seems to have a variety of
	eponymous hero’s quest for eternal		health benefits.
	life. Most religions offer an	6	Instead, Mr Stipp propounds a
	attenuated version of [id:96418] in which		relatively new theory that low-calorie
	the soul endures even after the body		diets activate genes designed to help
	has died. Medieval alchemists hunted		animals endure hard times, which
	in vain for the rejuvenating		boost cellular repair mechanisms.
	Philosopher’s Stone; industrial-age		There is evidence that almost all
	quacks got rich off their patent elixirs.		animals, including humans, may have
	Today, cosmetics companies dance		a similar suite of genes. Proponents
	around truth-in-advertising laws to		of this theory are searching for drugs,
	imply that their creams and lotions		so-called “calorie-restriction
	can keep the years at bay.		mimetics”, that can produce these
2	Yet for all the gloomy fascination		effects without requiring aspiring
	that surrounds ageing, precious little		centenarians to endure 100 years of
	research has been done into its		non-stop dieting. Several firms have
	causes. The question of why we grow		been set up to capitalise on the
	old and die still divides evolutionary		findings, in the hope of developing
	biologists. Strictly speaking, ageing		and selling pills that grant longer,
	does not seem to be inevitable. After		healthier lives.
	all, both cancer cells and some very	7	The book’s tone is refreshing,
	simple forms of life appear highly		although its occasional passages of
	resistant to the passage of time. And		lazy journalese can be jarring.
	while we know plenty about the		Mr Stipp is clearly enthusiastic about
	consequences of ageing, we know		the possibility of life extension, and
	much less about the exact biological		he mostly manages to avoid the
	processes involved. The little interest		breathless prose that mars so much
	shown was until recently limited to		reporting on the subject. Hype is an
	quacks and cranks, leavened with the		occupational hazard of anti-ageing
	occasional iconoclastic scientist		research. There is a great temptation
	(such as Peter Medawar, a brilliant		(rising with age) to inflate small
	British zoologist) with a reputation		advances into the idea that serious
	strong enough to survive developing		life extension, or even immortality, is
	an interest in a thoroughly		just around the corner. It isn’t. But
	disreputable field.		the discoveries of anti-ageing
3	In the past couple of decades that		researchers suggest that some
	has begun to change. Improvements		modest improvement in life
	in technology, particularly the ability		expectancy, and a big reduction in
	to sequence DNA quickly, have made		the diseases of old age, are indeed
	the serious study of ageing possible.		pharmaceutically possible. Ageing,
	All this is carefully chronicled in “The		reckons Mr Stipp, is on the verge of
	Youth Pill” by David Stipp, a former		becoming a respectable subdiscipline
	medical writer for the Wall Street		of medicine. That would be
	Journal and an able guide to this		quite enough to constitute a
	young science. His book draws		revolution in its own right.
	readers down the blind alleys and	8	The final part of the book is
	experimental dead ends that are an		philosophical, and considers whether
	inevitable part of [id:96420] , as well as		extending lifespan is something
	explaining the advances that have		worth aiming for. Some religious
	been made and the hunches that led		leaders and self-appointed sages
	to them.		have offered a variety of portentous
4	Plenty of progress has already		reasons for embracing decrepitude
	been made. Genes have been found		instead of fighting it. Happily,
	that boost the lifespans of laboratory		Mr Stipp has little patience for such
	animals by 30% or more, and		homilies, and demolishes them
	research into the mechanisms of		convincingly.
	ageing has fingered some tantalising
	leads. Ageing seems to be		The Economist, 2010