Responsible Investor

The future of population

Demographic trends and the sustainability of global resources: interview with Alisa Kaps

“Even if progress to achieve the UN Sustainable Development Goals might lead to a further increase in world population at first, it is without alternative. Only socioeconomic development will lead to a deceleration of population growth in the long run”.

Alisa Kaps is a member of the Berlin Institute for Population and Development, one of the best independent think tanks that deal with the causes and consequences of regional and global demographic changes. In this interview she examines the possible effects of an increase in the world population that could reach 10 billion by 2050.

UN World Population Prospect projections on the demographic trends says that in 2050 world population will be around 10 billion. What is your opinion on this trend?

According to the medium variant of the UN projections, the world’s population will increase by more than 2 billion people from today on. This figure is based on the assumption that fertility will decline for less developed countries, where women still have many children, and that it will slightly increase in countries, where women have fewer than two children on average. Whether or not nearly 10 billion people will live on earth by 2050 therefore highly depends on the development of the poorest regions in the world, especially Sub-Saharan Africa, where relative population growth is and will be highest. There is inherent uncertainty in population projections, because mortality and especially fertility may develop differently from the assumptions. Therefore, statistical methods are used to determine how plausible the outcomes are. The statistical analysis undertaken by the United Nations has concluded that, with a certainty of 95 per cent, the global population will stand between 9.4 and 10.2 billion in 2050. It thus seems safe to assume that in 2050 the world population will be around 10 billion, especially since UN population projections have been quite reliable in the past.


We can say that natural resources on Earth are limited and therefore there is a specific limit of sustainability? Are we close to reach it?

It is hard to say whether and at what point our planet is or will be “overpopulated” as the question of sustainability hinges not so much on the number of people, but rather on their lifestyle. There certainly is an over usage of the Earth’s resources, especially in highly developed countries. Due to their high standard of living, they occupy a large share of the world’s resource consumption and production of emissions. That is why even though their population is stable or even declining, it could be said that they are “ecologically overpopulated”.


If yes, I guess this limit depends on the capacity we have to lower our expectations and our needs, or not?

In most of the developed countries and some emerging countries, such as China, the problem can only be solved through emission-free technologies and a more environmentally conscious behaviour, which would mean some form of restriction regarding the standard of living of their citizens. At the same time, poor countries need to make progress in their socio-economic development in order to see reductions in the growth of their populations. We know that fertility rates only decline when living conditions as a whole improve. This necessary socioeconomic advancement will lead to an enormous consumption of resources and energy even when using the best and most environmental friendly technologies. It is therefore all the more important for developed countries to change their unsustainable behaviour in order to give the poor countries more room for their development.


Is there a direct relationship between the 17 SDGs of the UN and the world population? For example in Africa, despite massive investments in renewable energy, access to clean and low-cost energy (Objective number 7) risks diminishing due to demographic trend.

Population growth makes it in fact harder for poor countries, especially in Sub-Saharan Africa, to provide basic infrastructure for an increasing number of citizens. That is for example true for access to affordable and clean energy, but also for providing sufficient health care, schools or jobs which affect objective 3, 4 and 8 of the SDG’s. In a study on the Millennium Development Goals, which preceded the SDGs, we found out that some of the success was virtually “eaten up” by population growth. Between 1990 and 2010, the Least Developed Countries were able to reduce the share of people living in poverty by 29 per cent. Within the same time frame their population increased by 34 per cent. As a result, the number of the poor reached 388 million people in 2010 – 58.5 million more than the initial figure.


Apparently some of the SDGs seem to lead to a further increase in the world population, such as number 2, 3, 8 and 13. Not so?

The SDG objectives to “End hunger” (number 2) and to “Ensure healthy lives” (number 3) can indeed have the side effect of a population increase – at least in the short term. Better nutrition and an improvement in health care will for example further reduce infant and under-five mortality rates and thereby increase overall population figures. But if more children survive, parents usually also decide to have fewer which leads to decreasing birth rates after a relatively short period of time.

Therefore, even if progress to achieve the SDGs might lead to a further increase in world population at first, it is without alternative. Only socioeconomic development – which includes among other things good nutrition and health – will lead to a deceleration of population growth in the long run.


What are the most urgent measures to prevent the demographic explosion? And how likely are they to be implemented by 2030?

Besides the need for further improvements in measures for family planning (part of SDG 3) and more gender equality (SDG 5), better education (SDG 4) will surely have the biggest impact on demographic trends – partly because it affects objective 3 and 5 but also target 8 (decent work and economic growth) of the SDGs. Better educational attainment of a population not only leads to a higher economic growth and rising incomes but also to better health. Girl’s education is of special importance because better-educated women decide for much smaller families and thus have a significant impact on the population dynamics of their countries. However, providing primary and secondary education for all children and youth worldwide by 2030 is a goal out of reach for most poor countries. In Sub-Saharan Africa, some countries might not even achieve the Millennium Development Goal of universal primary education, which should have been accomplished by 2015, within the next 12 years.