Food and population growth.

It was a pleasure to read "Infectious Disease: The Human Cost of Our Environmental Errors" by Weinhold (2004). His article on microbes, people, and human environmental errors has encouraged me to share new and apparently unforeseen data that appear to contradict popular and even scientific ideas regarding human population dynamics. Emerging scientific evidence indicates that the absolute population numbers of species on the planet increase primarily as a function of food supply and also that microorganisms and human organisms have common dynamics governing population.

Abundant research indicates that countries such as Australia, Canada, Italy, and Tunisia, among many others, have shown a declining trend in their rates of human population growth (United Nations Development Programme 2003). The geographically localized data need not blind us to the fact that the global population is still growing by the billions.

For too long, human population growth has been widely viewed as somehow outside the course of nature. The potential causes of human population growth have seemed complex, obscure, numerous, or even unknowable, so that a strategy to address the problem has been thought to be all but impossible. One of the consequences of this unnatural way of viewing human population dynamics is that forecasts of global population growth vary widely: Some forecasting data indicate the end to human population growth soon, and other data suggest skyrocketing numbers.

With recent correlation data from Hopfenberg and Pimentel (2001) and the current mathematical formulation of the problem by Hopfenberg (2003), it may now be possible for us to see human population dynamics as a natural phenomenon. Hopfenberg (2003) and Hopfenberg and Pimentel (2001) provided an empirical presentation of a nonrecursive biological problem that is independent of ethical, social, legal, religious, and cultural considerations. This means that world human population growth is a rapidly cycling positive-feedback loop, a relationship between food and population in which food availability drives population growth, and population growth fuels the impression that food production needs to be increased. The data indicate that as we increase food production every year, the number of people increases, too.

Perhaps a new biological understanding is emerging with Hopfenberg's research. It is simply that the earth's carrying capacity for human organisms, like that for other organisms, is determined by food availability. As goes the food supply, so goes the population. According to these data (Hopfenberg 2003; Hopfenberg and Pimentel 2001), stabilization of food production at current levels will lead to a stabilization of absolute global human population numbers. Redistribution of world food resources and education for all children, in particular, appear in the forseeable future. Socially and culturally sanctioned humanitarian policies and programs regarding the propagation of our species will be developed and implemented. Human population growth is a huge problem, taking an ever-increasing toll on the Earth's resources; but we can take the measure of this problem and find a remedy that is consonant with universally shared human values.

The author declares he has no competing financial interests.

REFERENCES

Hopfenberg R. 2003. Human carrying capacity is determined by food availability. Popul Environ 25(2):109-117.

Hopfenberg R, Pimentel D. 2001. Human population numbers as a function of food supply. Environ Dev Sustain 3(1):1-15.

United Nations Development Programme. 2003. Human Development Indicator 2003: Demographic Trends, Annual Population Growth Rate (%). Available: http:// www.undp.org/hdr2003/indicator/indic_38_1_1.html [accessed 2 April 2004].

Weinhold 8 2004. Infectious disease: the human cost of our environmental errors. Environ Health Perspect 112:A32-A39.

Steven Earl Salmony

Disability Determination Service

Social Security Administration

Raleigh, North Carolina 

E-mail: [e-mail]