{"id":987,"date":"2018-06-30T09:17:18","date_gmt":"2018-06-30T09:17:18","guid":{"rendered":"http:\/\/163.180.4.222\/lab\/?p=987"},"modified":"2019-10-15T18:53:31","modified_gmt":"2019-10-15T09:53:31","slug":"theres-no-limit-to-longevity-says-study-that-revives-human-lifespan-debate","status":"publish","type":"post","link":"https:\/\/biochemistry.khu.ac.kr\/lab\/?p=987","title":{"rendered":"There\u2019s no limit to longevity, says study that revives human lifespan debate"},"content":{"rendered":"

 <\/p>\n

 <\/p>\n

Old questions, new answers! \uc778\uac04\uc758 \uc218\uba85\uc740?<\/p>\n

 <\/p>\n

 <\/p>\n

(\uc6d0\ubb38<\/a>)<\/p>\n

 <\/p>\n

 <\/p>\n

Death rates in later life flatten out and suggest there may be no fixed limit on human longevity, countering some previous work.<\/h6>\n

 <\/p>\n

 <\/p>\n

\n
\n
\n
\"\"<\/div>\n<\/div>
\n

Emma Morano, an Italian supercentenarian who died in 2017 at the age of 117, was the world’s last surviving person born in the 19th century.<\/span>Credit: Antonio Calanni\/AP\/REX\/Shutterstock<\/p>\n<\/figcaption><\/figure>\n

 <\/p>\n

 <\/p>\n

There might be no natural limit to how long humans can live \u2014 at least not one yet in sight \u2014 contrary to the claims of some demographers and biologists.<\/p>\n

That\u2019s according to a statistical analysis published Thursday in\u00a0Science<\/i>1<\/a><\/sup>on the survival probabilities of nearly 4,000 \u2018super-elderly\u2019 people in Italy, all aged 105 and older.<\/p>\n

A team led by Sapienza University demographer Elisabetta Barbi and University of Roma Tre statistician Francesco Lagona, both based in Rome, found that the risk of death \u2014 which, throughout most of life, seems to increase as people age \u2014 levels off after age 105, creating a \u2018mortality plateau\u2019. At that point, the researchers say, the odds of someone dying from one birthday to the next are roughly 50:50 (see \u2018Longevity unlimited\u2019).<\/p>\n

\u201cIf there is a mortality plateau, then there is no limit to human longevity,\u201d says Jean-Marie Robine, a demographer at the French Institute of Health and Medical Research in Montpellier, who was not involved in the study.<\/p>\n

That would mean that someone like Chiyo Miyako, the Japanese great-great-great-grandmother who, at 117, is the world\u2019s oldest known person, could live for years to come \u2014 or even forever, at least hypothetically.<\/p>\n

Researchers have long debated whether humans have an upper age limit. The consensus holds that the risk of death steadily increases in adulthood, up to about age 80 or so. But there\u2019s vehement disagreement about what happens as people enter their 90s and 100s.<\/p>\n

Some scientists have examined demographic data and concluded that there is a fixed, natural \u2018shelf-life\u2019 for our species and that mortality rates keep increasing. Others have looked at the same data and concluded that the death risk flattens out in one\u2019s ultra-golden years, and therefore that human lifespan does not have an upper threshold.<\/p>\n

 <\/p>\n

 <\/p>\n

\n
\n
\"\"<\/div>\n<\/div>\n<\/figure>\n

 <\/p>\n

 <\/p>\n

Age rage<\/b><\/p>\n

In 2016, geneticist Jan Vijg and his colleagues at Albert Einstein College of Medicine in New York City rekindled the debate when they analysed the reported ages at death for the world\u2019s oldest individuals over a half-century. They estimated that human longevity hit a ceiling at about 115 years \u2014 125 tops.<\/p>\n

Vijg and his team argued2<\/a><\/sup>\u00a0that with few, if any, gains in maximum lifespan since the mid-1990s, human ageing had reached its natural limit. The longest known lifespan belongs to Jeanne Calment, a French super-centenarian who died in 1997 at age 122.<\/p>\n

Experts challenged the statistical methods in the 2016 study, setting off a firestorm into which now step Barbi and Lagona. Working with colleagues at the Italian National Institute of Statistics, the researchers collected records on every Italian aged 105 years and older between 2009 and 2015 \u2014 gathering certificates of death, birth and survival in an effort to minimize the chances of \u2018age exaggeration\u2019, a common problem among the oldest old.<\/p>\n

They also tracked individual survival trajectories from one year to the next, rather than lump people into age intervals as previous studies that combine data sets have done. And by focusing just on Italy, which has one of the highest rates of centenarians per capita in the world, they avoided the issue of variation in data collection among different jurisdictions.<\/p>\n

As such, says Kenneth Howse, a health-policy researcher at the Oxford Institute of Population Ageing in the United Kingdom, \u201cthese data provide the best evidence to date of extreme-age mortality plateaus in humans\u201d.<\/p>\n

Ken Wachter, a mathematical demographer at the University of California, Berkeley, and an author of the latest study, suspects that prior disputes over the patterns of late-life mortality have largely stemmed from bad records and statistics. \u201cWe have the advantage of better data,\u201d he says. \u201cIf we can get data of this quality for other countries, I expect we\u2019re going to see much the same pattern.\u201d<\/p>\n

Robine is not so sure. He says that unpublished data from France, Japan and Canada suggest that evidence for a mortality plateau is \u201cnot as clear cut\u201d. A global analysis is still needed to determine whether the findings from Italy reflect a universal feature of human ageing, he says.<\/p>\n

 <\/p>\n

 <\/p>\n

Off limits<\/b><\/p>\n

The world is home to around 500,000 people aged 100 and up \u2014 a number that\u2019s predicted to nearly double with each coming decade. Even if the risk of late-life mortality remains constant at 50:50, the swelling global membership in the 100-plus club should translate into a creep upwards in the oldest person alive by about one year per decade, says Joop de Beer, a longevity researcher at the Netherlands Interdisciplinary Demographic Institute in The Hague.<\/p>\n

Many researchers say they hope to better understand what\u2019s behind the levelling off of mortality rates in later life. Siegfried Hekimi, a geneticist at McGill University in Montreal, Canada, speculates that the body\u2019s cells eventually reach a point where repair mechanisms can offset further damage to keep mortality rates level.<\/p>\n

\u201cWhy this plateaus out and what it means about the process of ageing \u2014 I don\u2019t think we have any idea,\u201d Hekimi says.<\/p>\n

For James Kirkland, a geriatrician at the Mayo Clinic in Rochester, Minnesota, the strong evidence for a mortality plateau points to the possibility of forestalling death at any age. Some experts think that the very frail are beyond repair. But if the odds of dying don\u2019t increase over time, he says, interventions that slow ageing are likely to make a difference, even in the extremely old.<\/p>\n

Not everyone buys that argument \u2014 or the conclusions of the latest paper.<\/p>\n

Brandon Milholland, a co-author of the 2016\u00a0Nature<\/i>\u00a0paper, says that the evidence for a mortality plateau is \u201cmarginal\u201d, as the study included fewer than 100 people who lived to 110 or beyond. Leonid Gavrilov, a longevity researcher at the University of Chicago in Illinois, notes that even small inaccuracies in the Italian longevity records could lead to a spurious conclusion.<\/p>\n

Others say the conclusions of the study are biologically implausible. \u201cYou run into basic limitations imposed by body design,\u201d says Jay Olshansky, a bio-demographer at the University of Illinois at Chicago, noting that cells that do not replicate, such as neurons, will continue to wither and die as a person ages, placing upper boundaries on humans’ natural lifespan.<\/p>\n

This study is thus unlikely to be the last word on the age-limit dispute, says Haim Cohen, a molecular biologist at Bar-Ilan University in Ramat-Gan, Israel. \u201cI\u2019m sure that the debate is going to continue.\u201d<\/p>\n<\/div>\n

 <\/p>\n

doi: 10.1038\/d41586-018-05582-3<\/div>\n

 <\/p>\n

 <\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

    Old questions, new answers! \uc778\uac04\uc758 \uc218\uba85\uc740?     (\uc6d0\ubb38)     Death rates in later life flatten out and suggest there may be(more…)<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[33,29,30],"tags":[7,3,4],"class_list":["post-987","post","type-post","status-publish","format-standard","hentry","category-do-biology","category-lets-do-science","category-recent-science-news","tag-do-biology","tag-lets-do-science","tag-recent-science-news"],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack-related-posts":[{"id":957,"url":"https:\/\/biochemistry.khu.ac.kr\/lab\/?p=957","url_meta":{"origin":987,"position":0},"title":"Oaks last 800 years with help of DNA double take","author":"biochemistry","date":"June 25, 2018","format":false,"excerpt":"\u00a0 \u00a0 (\uc6d0\ubb38) \u00a0 \u00a0 The long lifespan of the pedunculate oak, also known as the English oak, may stem from an extra helping of genes for disease resistance. Credit: Gustaf Emanuelsson\/Folio\/Getty Oaks last 800 years with help of DNA double take Iconic tree may owe its long life to\u2026","rel":"","context":"In "Let's Do Biology!"","block_context":{"text":"Let's Do Biology!","link":"https:\/\/biochemistry.khu.ac.kr\/lab\/?cat=33"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":898,"url":"https:\/\/biochemistry.khu.ac.kr\/lab\/?p=898","url_meta":{"origin":987,"position":1},"title":"Animals feel safer from humans in the dark","author":"biochemistry","date":"June 16, 2018","format":false,"excerpt":"\u00a0 \u00a0 (\uc6d0\ubb38: \uc5ec\uae30\ub97c \ud074\ub9ad\ud558\uc138\uc694~) \u00a0 Science\u00a0\u00a015 Jun 2018: Vol. 360, Issue 6394, pp. 1185-1186 DOI: 10.1126\/science.aau1311 \u00a0 \u00a0 Summary About 75% of Earth's land surface is currently modified by human activities (1). The expanding footprint of human activities is not only causing the loss of habitat and biodiversity but\u2026","rel":"","context":"In "Let's Do Biology!"","block_context":{"text":"Let's Do Biology!","link":"https:\/\/biochemistry.khu.ac.kr\/lab\/?cat=33"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1434,"url":"https:\/\/biochemistry.khu.ac.kr\/lab\/?p=1434","url_meta":{"origin":987,"position":2},"title":"Humans as models of human disease","author":"biochemistry","date":"August 24, 2018","format":false,"excerpt":"\u00a0 \u00a0 (\uc6d0\ubb38: \uc5ec\uae30\ub97c \ud074\ub9ad\ud558\uc138\uc694~) \u00a0 Science\u00a0\u00a024 Aug 2018: Vol. 361, Issue 6404, pp. 763-764 DOI: 10.1126\/science.361.6404.763-e \u00a0 Mice are a convenient model for exploring the functions of cellular signaling pathways. Occasionally, however, an \u201cexperiment of nature\u201d highlights the perils of overreliance on mice. RIPK1 is a well studied protein\u2026","rel":"","context":"In "Let's Do Biology!"","block_context":{"text":"Let's Do Biology!","link":"https:\/\/biochemistry.khu.ac.kr\/lab\/?cat=33"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1518,"url":"https:\/\/biochemistry.khu.ac.kr\/lab\/?p=1518","url_meta":{"origin":987,"position":3},"title":"\uae30\uc220\uc774 \ubc1c\ub2ec\ud574\uc57c \uc0dd\ubb3c\ud559 \ud601\uc2e0 \uc628\ub2e4","author":"biochemistry","date":"September 2, 2018","format":false,"excerpt":"\u00a0 \u00a0 (\uc6d0\ubb38: \uc5ec\uae30\ub97c \ud074\ub9ad\ud558\uc138\uc694~) \u00a0 \u00a0 \uacfc\ud559\uc790\uac00 \uc138\uc6b4 \uac00\uc124\uc740 \uc2e4\ud5d8\uc774\ub098 \uad00\uce21\uc744 \ud1b5\ud574 \uac80\uc99d\ub418\uae30 \uc804\uc5d4 \uacfc\ud559\uc801 \uc9c0\uc2dd\uc73c\ub85c \uc778\uc815\ubc1b\uc9c0 \ubabb\ud55c\ub2e4. \uc9c0\ub09c 2016\ub144 3\uc6d4, \ub808\uc774\uc800 \uac04\uc12d\uacc4 \uc911\ub825\ud30c \uad00\uce21\uc18c(LIGO)\uc758 \uc7a5\ube44\ub97c \ud1b5\ud574 \uc54c\ubc84\ud2b8 \uc544\uc778\uc288\ud0c0\uc778\uc774 100\uc5ec \ub144\uc804 \uc608\uce21\ud588\ub358 \uc911\ub825\ud30c\uac00 \ubaa8\uc2b5\uc744 \ub4dc\ub7ec\ub0c8\ub2e4. \uc911\ub825\ud30c \uad00\uce21\uae30\uc220\uc774 \ub354 \ub2a6\uac8c \uac1c\ubc1c\ub410\ub2e4\uba74 \uc544\uc778\uc288\ud0c0\uc778\uc758 \uc0dd\uac01\uc740 \ub354 \uc624\ub7ab\ub3d9\uc548 \uac00\uc124\ub85c \uba38\ubb3c\ub7ec\uc57c \ud588\uc744 \uac83\uc774\ub2e4. \ud754\ud788\u2026","rel":"","context":"In "Essays on Science"","block_context":{"text":"Essays on Science","link":"https:\/\/biochemistry.khu.ac.kr\/lab\/?cat=32"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":402,"url":"https:\/\/biochemistry.khu.ac.kr\/lab\/?p=402","url_meta":{"origin":987,"position":4},"title":"Write fiction to discover something new in your research","author":"biochemistry","date":"May 30, 2018","format":false,"excerpt":"\u00a0 \u00a0 (\uc6d0\ubb38) \u00a0 \u00a0 Creative writing can help you to approach your science from a completely different perspective \u2014 and boost its impact, says Amanda C. Niehaus. \u00a0 \u00a0 Credit: Getty \u00a0 In the final month of my Australian Research Council fellowship at the University of Queensland in Brisbane,\u2026","rel":"","context":"In "Essays on Science"","block_context":{"text":"Essays on Science","link":"https:\/\/biochemistry.khu.ac.kr\/lab\/?cat=32"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":953,"url":"https:\/\/biochemistry.khu.ac.kr\/lab\/?p=953","url_meta":{"origin":987,"position":5},"title":"Gene important in pregnancy shows evolution in action","author":"biochemistry","date":"June 25, 2018","format":false,"excerpt":"\u00a0 \u00a0 (\uc6d0\ubb38) \u00a0 \u00a0 \u00a0 Childbirth and pregnancy might be influenced by variations in the progesterone-receptor gene, which shows wide diversity in humans. Credit: BSIP\/UIG\/Getty Gene important in pregnancy shows evolution in action Human populations have different forms of a gene encoding a hormone receptor. \u00a0 \u00a0 A pregnancy-related\u2026","rel":"","context":"In "Let's Do Biology!"","block_context":{"text":"Let's Do Biology!","link":"https:\/\/biochemistry.khu.ac.kr\/lab\/?cat=33"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"jetpack_sharing_enabled":false,"jetpack_shortlink":"https:\/\/wp.me\/p9Xo1j-fV","_links":{"self":[{"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=\/wp\/v2\/posts\/987","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=987"}],"version-history":[{"count":1,"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=\/wp\/v2\/posts\/987\/revisions"}],"predecessor-version":[{"id":4386,"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=\/wp\/v2\/posts\/987\/revisions\/4386"}],"wp:attachment":[{"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=987"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=987"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/biochemistry.khu.ac.kr\/lab\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=987"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}