Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

The coming acceleration of global population ageing


The future paths of population ageing result from specific combinations of declining fertility and increasing life expectancies in different parts of the world1. Here we measure the speed of population ageing by using conventional measures and new ones that take changes in longevity into account for the world as a whole and for 13 major regions. We report on future levels of indicators of ageing and the speed at which they change. We show how these depend on whether changes in life expectancy are taken into account. We also show that the speed of ageing is likely to increase over the coming decades and to decelerate in most regions by mid-century. All our measures indicate a continuous ageing of the world’s population throughout the century. The median age of the world’s population increases from 26.6 years in 2000 to 37.3 years in 2050 and then to 45.6 years in 2100, when it is not adjusted for longevity increase. When increases in life expectancy are taken into account2,3, the adjusted median age rises from 26.6 in 2000 to 31.1 in 2050 and only to 32.9 in 2100, slightly less than what it was in the China region in 2005. There are large differences in the regional patterns of ageing. In North America, the median age adjusted for life expectancy change falls throughout almost the entire century, whereas the conventional median age increases significantly. Our assessment of trends in ageing is based on new probabilistic population forecasts. The probability that growth in the world’s population will end during this century is 88%, somewhat higher than previously assessed4. After mid-century, lower rates of population growth are likely to coincide with slower rates of ageing.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1
Figure 2: The changing speed of increase in selected indicators of ageing.
Figure 3
Figure 4: Fractiles of the projected uncertainty distribution of the proportion of the population above age 80 in Western Europe.


  1. United Nations. World Population Ageing 2007 (United Nations, New York, 2007)

  2. Sanderson, W. & Scherbov, S. Average remaining lifetimes can increase as human populations age. Nature 435, 811–813 (2005)

    Article  CAS  ADS  Google Scholar 

  3. Sanderson, W. & Scherbov, S. A new perspective on population aging. Demog. Res. 16, 27–58 (2006)

    Article  Google Scholar 

  4. Lutz, W., Sanderson, W. & Scherbov, S. The end of world population growth. Nature 412, 543–545 (2001)

    Article  CAS  ADS  Google Scholar 

  5. Harper, S. Ageing Societies: Myths, Challenges and Opportunities (Hodder Arnold, London, 2006)

    Google Scholar 

  6. Ryder, N. Notes on stationary populations. Popul. Index 41, 3–28 (1975)

    Article  Google Scholar 

  7. Hersch, L. De la démographie actuelle à la démographie potentielle. Melange des Études Economiques Offertes à William Rappard (Georg, Geneva, 1944)

    Google Scholar 

  8. Panush, N. & Peritz, E. Potential demography. Eur. J. Popul. 12, 27–39 (1996)

    Article  CAS  Google Scholar 

  9. Bongaarts, J. How long do we live? Popul. Dev. Rev. 32, 605–626 (2006)

    Article  Google Scholar 

  10. Oeppen, J. & Vaupel, J. Broken limits to life expectancy. Science 296, 1029–1031 (2002)

    Article  CAS  Google Scholar 

  11. Carnes, B. & Olshansky, S. J. A realistic view of aging, mortality and future longevity. Popul. Dev. Rev. 33, 367–381 (2007)

    Article  Google Scholar 

  12. National Research Council. Beyond Six Billion: Forecasting the World’s Population (eds Bongaarts J. & Bulatao R., Panel on Population Projections, Committee on Population, Commission on Behavioral and Social Sciences and Education) (National Academy Press, Washington DC, 2000)

  13. Lee, R. & Carter, L. Modeling and forecasting U.S. mortality. J. Am. Stat. Assoc. 87, 659–671 (1992)

    MATH  Google Scholar 

  14. Manton, K., Stallard, E. & Trolley, H. Limits to human life expectancy: evidence, prospects and implications. Popul. Dev. Rev. 17, 603–637 (1991)

    Article  Google Scholar 

  15. Fries, J. Aging, natural death, and the compression or morbidity. N. Engl. J. Med. 303, 130–135 (1980)

    Article  CAS  Google Scholar 

  16. Keilman, N. Ex-post errors in official population forecasts in industrialized countries. J. Off. Stat. 13, 245–277 (1997)

    Google Scholar 

  17. United Nations. World Population to 2300 (and associated database) (United Nations, New York, 2004)

  18. Lutz, W., Scherbov, S., Cao, G. Y., Ren, Q. & Zheng, X. China’s uncertain demographic present and future. Vienna Yb. Pop. Res. 2007, 37–59 (2007)

    Article  Google Scholar 

  19. Lutz, W., Sanderson, W. & Scherbov, S. in The End of World Population Growth in the 21st Century: New Challenges for Human Capital (eds Lutz, W., Sanderson, W. & Scherbov, S.) 17–84 (London, Earthscan, 2004)

    Google Scholar 

Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to Wolfgang Lutz.

Supplementary information

Supplementary Information

The file contains Supplementary Tables 1-3 and Supplementary Figure 1. The Supplementary Information shows the results of IIASA’s new probabilistic population projections for 13 world regions and for the world as a whole (selected indicators for selected years). Information about more indicators and for single years of time can be found at or directly from the corresponding author (PDF 188 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Lutz, W., Sanderson, W. & Scherbov, S. The coming acceleration of global population ageing. Nature 451, 716–719 (2008).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing