A Brief on Overpopulation – Why it Matters and What You Can Do About It

Erin Brown | April 4, 2023 | Leave a Comment

As humanity has surpassed the 8 billion people milestone, it is more important now than ever to talk about population. What will we do if we continue to grow at exponential rates? What are ethical, viable strategies to decrease population?

“First off, let me get this straight, discussing addressing overpopulation does not mean discussing killing people. The goal is actually to prevent it.” – Dr. Jane O’Sullivan

Current world population in January 2023: 8 billion

The current rate of population growth is around 80 million people per year. There are over 8 billion people on the planet, the last billion added in less than the last 12 years. 

The Earth’s first billion people milestone took from the beginning of human history until the 1800s to be achieved. Then, due to the industrial revolution, humanity reached the second billion mark by 1930 (taking only 130 years), reached the third billion in 1960 (only took 30 years), then reached the fourth billion by 1974 (only took 14 years), and the fifth billion by 1987 (only took 13 years). We hit 6 billion in 1999 (which took 12 years) and hit 7 billion in 2011 (which took about 12 years). At the current growth rate, the world population will reach 9 billion by 2037 and 10 billion by 2057.

The growth rate is declining, but not at a fast enough rate to combat the exponential compound growth. The growth rate was 2% in the 1970s. Now it is 1.05%. Any growth rate above 1% means we are still adding more people to the planet every year. 

What is overpopulation? 

Overpopulation is a human population in numbers high enough to cause environmental deterioration, impaired quality of life, or population crash. 

Why is overpopulation an issue? 

Overrun natural resources can only lead to death by starvation, conflict, and disease, and the only viable alternative is voluntary restraint on human births.

What is carrying capacity?

Carrying capacity is defined as the maximum population of a species that an area will support without undergoing deterioration. 

Paul R. Ehrlich and other scientists estimate the world’s optimum population for carrying capacity (at a comfortable standard of living – editor’s note) to be less than two billion people – 6 billion fewer than on the planet today. “But the longer humanity pursues business as usual, the smaller the sustainable society is likely to prove to be. We’re continuously harvesting the low-hanging fruit, for example by driving fisheries stocks to extinction” – Paul Ehrlich says.

How do we revert population overshoot to a sustainable population level? 

Geologist Art Berman explains population overshoot this way: “Overshoot means that humans are using natural resources and polluting at rates beyond the planet’s capacity to recover. The main cause of overshoot is the extraordinary growth of the human population made possible by fossil energy. Concerns about overshoot and population raised more than 40 years ago were dismissed. Climate change has captured public awareness more recently although many doubt that it is an emergency. Overshoot is more difficult to dispute; it destroys rainforests, leads to the extinction of other species, the pollution of land, rivers, and seas, the acidification of the oceans, and the loss of fisheries and coral reefs. People understandably want to know the solutions. Overshoot is the problem we must address. Any plan that includes continued growth is doomed to fail.”

What can we do? Jane O’Sullivan outlines the two options for addressing population overshoot – increase the Earth’s carrying capacity or decrease population.

Increasing Earth’s carrying capacity

We are already doing this by (a) using fewer natural resources per person, or (b) increasing productivity by finding more ways to use resources. This only defers the problem and creates collateral damage. 

Decreasing population numbers

If we talk about this now, the hope is to increase our options for solutions. One of the biggest challenges to facing overpopulation head-on and discussing a decreasing population are the stigmas and myths associated with reducing human population numbers. An elaborate set of myths has emerged in opposition to reducing population levels. These myths may prevent even environmentalists from viewing overpopulation as an issue. Jane O’Sullivan elucidates on the following six myths that make inaction a virtue.

Myth 1 – The human population is stabilizing, and birth rates are decreasing

Truth Birth rates started declining in the 1970s-90s due to family planning, but not low enough. The number of mothers is still increasing faster than family planning is decreasing the birth rate. We are still having more births per year than ever before. The total fertility rate has decreased, but as fertility decline has slowed to a trickle, the number of total births has continued to increase. 

Myth 2 – China is the only one with the problem and they used cruel methods (one-child policy)

Truth – Family planning programs have helped many countries successfully reduce births through voluntary means, including China, before the one-child policy.

Myth 3 – Poverty causes population growth, therefore development is the best contraceptive

I.e., family planning is unnecessary and inefficient as long as there is development.

Truth – If this was true, we would see the population decline as development increases. However, it is the decrease in fertility rates that drove economic development, not the other way around. This myth is therefore “correlation implying causation” in the wrong direction. The poorest countries could lower their population by family planning just as quickly as rich countries if they choose to prioritize it.

Countries of families with four or more children, on average, have the lowest level of development; in families with 3 children or fewer the level goes up by some degree, and with two or fewer children development soars. The current focus should be on expanding provisions for teachers, doctors, equality, etc. instead of just giving people what they need. 

Myth 4 – Educating girls is the key to ending population growth

Truth Another indirect approach that excludes a discussion on the benefit of small families and ending population growth. Educating girls helps but not much unless it is also flanked by family planning efforts. Family planning has a stronger effect on women regulating their fertility, decreasing the fertility gap between the educated and uneducated, and with family planning, girls are more likely to stay in school.

Myth 5 – Population growth is good for the economy

Truth This makes people poorer as shown under Myth #3. 

Myth 6 – Population growth in poor nations does not matter because of their “tiny carbon footprint”

Truth  Population growth is a greater threat than climate change. The best way for anyone to decrease their carbon footprint is to have one less kid.

Therefore, family planning is the most economical way to a sustainable future.

What action can each of us take?

1. Discuss smaller family sizes with your partner, family, and friends – how do we aim for birth rates lower than two children per couple?

2. Share information about the environmental impacts of population growth with friends and family. Advocate for action to reduce and reverse population growth.

3. Reassess concerns about aging – how can we shift away from worshipping eternal youth, to accepting and valuing the entire life cycle? 

4. Celebrate population decline – what are possible depopulation dividends? 

5. Support organizations and efforts that support family planning and women’s education.

Damien Carrington, an environmental editor at The Guardian, interviewed Prof. Paul Ehrlich about the solutions:

“The solutions are tough,” Ehrlich says. “To start, make modern contraception and backup abortion available to all and give women full equal rights, pay, and opportunities with men. Focus on overconsumption and equity issues. Specifically women’s rights and the explicit countering of racism.”

Ehrlich also says that an unprecedented redistribution of wealth is needed to end the over-consumption of resources, but “the rich who now run the global system – that hold the annual ‘world destroyer’ meetings in Davos – are unlikely to let it happen…Too many rich people in the world is a major threat to the human future, and cultural and genetic diversity are great human resources…It is a near certainty in the next few decades, and the risk is increasing continually as long as the perpetual growth of the human enterprise remains the goal of economic and political systems. As I’ve said many times, ‘perpetual growth is the creed of the cancer cell’.”

If cultural and genetic diversity are great human resources, how can the rich and the poor come together across the world to solve this issue?

Anne and Paul Ehrlich expand on their “vision for a cure”:

“Rich white people love to hold meetings to discuss the ‘population problem’ which always ends up focusing on the very real demographic difficulties of those with darker skin tones, especially people who live in Africa and Latin America. But isn’t it really time for the poor people of the world, especially those not in need of tanning beds, to extend a helping hand to the major villains of the destruction of humanity’s life-support systems? Could they not hold an educational conference in Washington, D.C. to explain why civilization is going down the drain, to the per-capita most environmentally destructive giant nation on the planet? Leaders from the “South” could both organize the event and supply experts to educate the wealthy and middle class on their ethical responsibilities and ways to meet them. We envision learning sessions on topics such as:

  • Avoiding the second child.
  • The population problem beyond numbers: inequality and waste of talent. 
  • Are borders ethical?
  • Population shrinkage for politicians.
  • GDP shrinkage for economists.
  • Do Trump and his colleagues prove that the lighter your skin, the lighter your brain?
  • Citizens United: It’s time for euthanasia for corporations.
  • Redistribution and survival.
  • Disbanding “Murder Incorporated”: gun manufacturers and big pharma.
  • How to end plastic production.
  • The historical contributions of the global South to the food enjoyed by the North.
  • How biodiversity loss is accompanied by the loss of human cultural diversity.
  • We know our populations are growing too fast; how to help us help ourselves?
  • Why anti-abortion laws kill poor women.

You can doubtless think of others. The possibilities are endless”.


Berman, Art. The Climate-Change Trip to Abilene. July 13, 2022. https://mahb.stanford.edu/library-item/the-climate-change-trip-to-abilene/

Carrington, Damien. Interview with Paul Ehrlich: Collapse of civilization is a near certainty within decades. July 9, 2020. https://www.theguardian.com/cities/2018/mar/22/collapse-civilisation-near-certain-decades-population-bomb-paul-ehrlich

Ehrlich, Anne H.; Ehrlich, Paul R. Overpopulation In America -And Its Cures. November 14, 2019. https://mahb.stanford.edu/blog/overpopulation-america-cures/

O’Sullivan, Jane. The tenth presentation at the Delivering the Human Future Conference. Titled: The Future of the Human Population. March 21, 2021. https://www.youtube.com/watch?v=shUNJPLpXpQ

Population Statistics. https://www.worldometers.info/world-population/

Erin Brown is a licensed mental health, marriage, and family therapist in Jacksonville, FL. She is trained in EMDR (eye movement desensitization and reprocessing), Play Therapy, and the Gottman Method Couples Therapy. She received her specialist’s degree at the University of Florida. Erin feels honored to be on the board of Family Foundations of Northeast Florida, Inc., which serves to help maximize the potential of individuals and families in Northeast Florida to lead better lives. 

The MAHB Blog is a venture of the Millennium Alliance for Humanity and the Biosphere. Questions should be directed to joan@mahbonline.org

The views and opinions expressed through the MAHB Website are those of the contributing authors and do not necessarily reflect an official position of the MAHB. The MAHB aims to share a range of perspectives and welcomes the discussions that they prompt.