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“Instead, ageing is an evolutionary oversight: a result of mutations accumulated which worsen fitness in old age but evolution can’t get rid of; antagonistically pleiotropic genes that maximise reproductive success in youth even if they have unfortunate unintended consequences in later life; and mechanisms that prioritise having children over maintaining our disposable somas.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“This is the fundamental reason for ageing �� evolution’s inability to keep old animals fit because they are less likely to have children.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“if we lived in a society where there was no ageing, would you invent ageing to solve one of these problems?”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“The risk of Parkinson’s is increased if you have a mutation in a gene called GBA, which codes for one of the digestive enzymes involved in autophagy. Parkinson’s is accompanied by ‘Lewy bodies��, clumps of a protein called alpha-synuclein that are toxic to brain cells. The problematic, sticky form of alpha-synuclein is normally degraded by autophagy, but even a small impairment caused by a minor GBA mutation is enough to slow its breakdown, increase its levels and thus increase the risk of getting Parkinson’s. Impaired autophagy is also associated with Alzheimer’s and Huntington’s disease, arthritis and heart problems.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“It’s estimated that every cell in your body suffers up to 100,000 assaults on its genetic code every day. On top of that, every time a cell divides this entire genetic code has to be duplicated. Thanks to the incomprehensible number of cells in your body and their fast rate of turnover, over your lifetime you’ll produce a couple of light years of DNA �� enough to stretch halfway to the nearest star �� in the form of ten quadrillion near-perfect copies of your two-metre personal genome. Even the highest-fidelity copying and proof-reading systems nature can devise will make occasional mistakes given that job spec.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“Instead, ageing is an evolutionary oversight: a result of mutations accumulated which worsen fitness in old age but evolution can’t get rid of;”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“and fall apart with time. All good things must come to a messy, high-entropy end, whether they’re steam engines, universes, or animals.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“conservation��. It implies that this response to reduced”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“So, if telomere length and telomerase levels are rather like walking a tightrope between aging and cancer, what practical interventions are there which might help us stay on the tightrope rather than falling off in either direction?”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“Though the effect varies by tissue, the most common is a reduction in elasticity, which you can easily see for yourself: a pinched patch of skin springs back into position ever more slowly with the advancing years.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“This can eventually result in an advanced glycation end product, or AGE, which is permanent.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“The obvious solution is stem cells and, while they’re not ready for the clinic yet, “thymus organoids”—small, artificial thymuses grown in the lab—have been shown to work when transplanted into mice without thymuses, and rapid progress is being made in generating thymuses from iPSCs, too.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“As a result, researchers are looking into gene therapy that could add an extra copy of FOXN1 into the cells of our ailing thymuses, or drugs which could turn our existing copies back on.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“They gave nine men a combination of human growth hormone (HGH) together with DHEA (another hormone) and metformin (the diabetes drug and potential anti-aging pill you might remember from the last chapter) to combat the diabetes risk associated with HGH. The results were positive, and quite wide-ranging: their thymuses look less fatty on an MRI scan and they have more T cells fresh from the thymus, as you’d hope—but they also saw improvements in kidney function and, most excitingly, a reduction in their epigenetic age, as measured by the morbidly accurate epigenetic clocks we met a couple of chapters ago. This suggests that rejuvenating the thymus can go on to rejuvenate the body more generally, not just the immune system—and, given the immune system’s wide remit for defense and maintenance around the body, perhaps this shouldn’t come as a surprise.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“DR mimetics are racing senolytics to be the first actual anti-aging treatment deployed in clinical care.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“Other naturally sourced contenders include resveratrol, a compound found in the skin of grapes; curcumin, one of the chemicals which makes turmeric yellow; aspirin, which on top of its many other physiological effects was recently found to enhance autophagy; and quercetin, which we met very recently as half of the D+Q duo. None of these quite has the firm evidence base to suggest that healthy people should take them preventatively, but there’s plenty of biochemical diversity there for researchers to explore.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“Spermidine activates autophagy, and has been shown to improve heart health and extend lifespan by 10 percent in mice, even if started late in life; suggestively, a study looking at the connection between diet and lifespan in humans found that those getting the most spermidine in their diet lived five years longer than those getting the least, even after correcting for other differences in their diets, lifestyle and general health. (Particularly high concentrations of spermidine are present in mushrooms, soybeans and cheddar cheese.) While observational studies should always be taken with a pinch of salt, together with the lifespan extension in mice this is exciting enough to inspire some proper trials, so watch this space.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“Though these efforts have been delayed by coronavirus, the scientists involved are trying to start a small-scale study to see if metformin could improve immunity in elderly people and thus strengthen their response against COVID-19.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“First, those side effects are observed at far higher doses of rapamycin than are needed for its use as an anti-aging medication. In fact, some of them are even entirely reversed when it’s given at lower doses—counterintuitively, while a high dose of rapamycin will suppress the immune system, a low dose doesn’t suppress it a bit as you might expect, but seems to enhance its performance.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“Rapamycin turned out to be much more than an anti-fungal agent. Further investigation showed that it was a powerful immune suppressant, and also stopped cells from multiplying.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“The second, published in 2013, is “The Hallmarks of Aging,�� and enumerates nine changes which fit three criteria. First, they need to increase with age: if they don’t, how could they be causing aging? Second, accelerating a hallmark’s progress should accelerate aging, and, third, slowing one should improve it—these two criteria are an attempt to separate things which are merely associated with aging from things that are actually contributing to it. Finally, these hallmarks also come with suggested interventions which could slow or reverse their progression, thus slowing or reversing that aspect of aging, and hopefully putting the brakes on the process overall.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“The first, originally published in 2002 and boldly entitled “Strategies for Engineered Negligible Senescence�� (SENS for short), was devised by maverick biogerontologist Aubrey de Grey. In its current form, SENS identifies seven differences between old bodies and young which de Grey suggests are the fundamental causes of aging.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“It’s foolhardy to pick a precise start date for a scientific field, but the emergence of biogerontology as a distinct, sizeable discipline arguably began in the 1990s—shockingly recent for a field which concerns itself with one of the most significant, near-universal phenomena which afflict living things.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“The prevailing tale in developing countries has been one of meteoric rises since 1950: life expectancy in India has almost doubled, from 36 in 1950 to 69 today.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“A 20-year-old today has better odds of having a living grandmother than a 20-year-old in the 1800s did of having a living mother.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“The cumulative effect of this incredible progress is that lives are now twice as long on average as they were in the early 1800s—life expectancy has gone from 40 years back then, to over 80 in the rich world today.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“Alternatively, for every day you survive, you gain another six hours—meaning that a good night’s sleep isn’t really time wasted, as you’re getting most of it back thanks to rising life expectancy.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“As the 1800s got into full swing, things finally began to change. Slowly, between 1830 and 1850, graphs of life expectancy start to pull up. If we take the leading country in the world at any given time, which we can regard as the state of the art in population health for any given moment in history, a very striking picture emerges. The maximum global life expectancy has increased by three months every year since 1840, with clockwork regularity.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“Many people’s initial reaction to the idea of treating aging is cautious, or even hostile: we wonder what the consequences of longer lifespans will be for population growth or the environment; if treatments for aging would primarily benefit the rich and powerful; or whether dictators could live forever, imposing endless totalitarianism. However, almost any objection can be answered by turning the question around and replacing it with a simple hypothetical alternative: if we lived in a society where there was no aging, would you invent aging to solve one of these problems?”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old

“These calculations show that a complete cure for cancer—currently the leading cause of death—would add less than three years to life expectancy. The numbers for runner-up heart disease are similarly slight: two years at best.”
― Andrew Steele, Ageless: The New Science of Getting Older Without Getting Old