Population Matters-USA – working for a sustainable world

Some words carry baggage, which may interfere with their utility, and even with their use. “Population” and “overpopulation” are examples of this vilification.

For years people concerned about the human effects on our environment have avoided using the word “overpopulation”. Is it time to end that taboo?

This word implies that there are too many people, and that we are injuring our environment. Thus, it is critical of humanity. To some, the word also recalls past histories of abuse, genocide and racism.

How many people does it take to be overpopulated? Thirty years ago, Professor Joel Cohen wrote the book “How Many People Can the Earth Support”. The answer to the title’s question is, “it depends”—in part it depends on our lifestyle. Cohen found a wide range, the maximum human population ranges from fewer than one billion to over 1000 billion people.

Here is a typical definition of “overpopulation”: “…when there are more people than can live on the earth in comfort, happiness, and health and still leave the world a fit place for future generations.” That definition looks at our use of limited resources, but it only considers the effect of too many people on our own species. What about the rest of the living world?

Philosophy professor Phil Cafaro suggests a new definition that considers the impacts both on humans and on the rest of life. In the abstract of a recent paper, he wrote:

“Human societies, or the world as a whole, are overpopulated when their populations are too large to preserve the ecosystem services necessary for future people’s wellbeing or to share the landscape fairly with other species.”

What is unique about this definition is that it includes harm to other flora and fauna, as well as to our own species.

My favorite way to measure human’s effect on the natural world is with the Ecological Footprint (EF). An individual’s EF is a measure of the demands made by a person on natural resources, using the areas of biologically productive land and water as its yardstick. Overall impact increases with increasing population, of course, and also increases with increasing consumption.

The planet can support more people if their consumption is low. For example, Kenya, a low-income country, has an average EF of 2 acres per person, versus the USA with over 20 acres. Currently, the global average EF of an individual is almost 7 acres.

Unfortunately, there is only enough productive land and water for each person to draw from 4 acres, on the average. Thus, using the Ecological Footprint as a measure, the planet is already overpopulated. Indeed, we are overpopulated by a whopping 75%! If, however, we all consumed as little as Kenyans, we would be fine.

Regrettably, there are not many people who want to decrease their consumption. Still fewer actually make the sacrifices necessary to consume less. Instead, many millions are trying to increase their income so they can consume more.

On the other hand, there is a long history of people aspiring to limit their fertility. For centuries women have tried to have control over their family size. All too many have risked death to abort unintended pregnancies. Now that effective contraception and safe abortion methods are available, the fertility rate is decreasing in most parts of the world. Sadly, the latest estimate is that over 250 million women want to avoid pregnancy but are not using modern, effective contraception. The “low hanging fruit” to approaching sustainability is to remove barriers to family planning.

Let’s accept that we are overpopulated, and start using that word fearlessly. I suggest that you explore The Overpopulation Project (https://overpopulation-project.com). You will find useful information about the relationship between human numbers and ecological sustainability.

©Richard Grossman MD, 2025

“The words ‘birth control’ and ‘population’ shouldn’t be in the same sentence. Indeed, they shouldn’t even be in the same room!”

I was interviewing the president of a company that markets contraceptives. She belongs to an ethnic group that has suffered from genocide and involuntary sterilization in the past. She was quite adamant that family planning should not be advocated as a means to help the environment.

Some words have adverse connotations to some people in certain situations. For instance, I used the word “vagina” in my work as an OB-GYN, but in many groups it would be rude to speak it. “Population” is one of the words that has become sullied in the recent past. My demographer friends talk about population all the time, but they don’t seem aware that there are many people who are antithetic to the word.

What is the meaning of “population”? One definition is: “the number of people in a country or region”, however that seems too simple. It has come to have the implication of “overpopulation”, as in the title of the Ehrlichs’ book, “The Population Bomb”.

Why does this simple word carry so much baggage? I think that there are several reasons. One is that some religions promote large families or prohibit the use of birth control; they follow the biblical admonition to “be fruitful and multiply”. In addition, focusing on human population forces us to take responsibility for environmental degradation.

Perhaps the main reason that “population” has negative connotations for many people is its past history of abuse. There have been two huge regrettable examples of population policies that ignored people’s civil and reproductive rights. China forced women to use contraception or to have abortions during its one child policy. In India, both men and women were forcibly sterilized during The Emergency, in the mid 1950s.

Unfortunately, there have been many smaller abuses of people’s reproductive rights. Sterilizations of poor Indigenous women in Peru is an example. That was part of Peru’s National Population Program during Fujimori’s reign. There have also been cases closer to home. Many “Mississippi appendectomies”—forced tubal ligations of Black women—have been documented. Native women also have been targeted, continuing the genocide of the 19^th century. The majority of states had eugenic laws in the early 20^th century, with forced sterilizations of “undesirable” people. Colorado was one of the exceptions without such a law.

Sterilization without consent is real. I assisted with an infertility operation many years ago. The patient had moved from Texas after getting divorced and remarrying. She had had 3 children by cesarean with her first husband, but hadn’t conceived with her new mate. At surgery we found that her tubes had been tied. The patient later told us that her doctor in Texas had not liked her first husband and had apparently done the tubal ligation without her consent or knowledge.

Both the Sierra Club and the National Audubon Society had population programs in the past. Then, they recognized the relationship between population growth and environmental problems, and had educational programs on that subject—but no longer. Apparently slowing population growth is too controversial for them, and for most other environmental groups.

It seems that the word “population” has bad connotations for many people now, including environmentalists. It brings up the specter of involuntary reproductive procedures done in order to limit world population growth or to get rid of certain populations of people.

“Population” is an important word, since the planet is already overpopulated. Therefore, need to pay attention to the word and remove barriers to access family planning. However, we also need to be aware of its bad baggage when we use it.