I suggest the occurrence of many diseases is dependent upon the decline of DHEA which begins around 20-25 years of age and reaches very low levels in old age.  Also, it follows from my work, that many problems that are increasing with time in the United States and in the world are resulting from the "secular trend," which I suggest is due to the increase in percentages of individuals of higher testosterone and the negative effect that testosterone exerts on the availability of DHEA.  Disturbances in "dehydroepiandrosterone homeostasis" may be a significant source of morbidity and mortality. 

(Copyright 2003, James Michael Howard, Fayetteville, Arkansas, U.S.A.)

Copyright © 1985-2023 James Michael Howard, Fayetteville, Arkansas, U.S.A.  All rights reserved. All pages are under construction and updated periodically due to new research. Nothing is sold at this site nor is any product or service endorsed anywhere.


Modern applications extends my work to modern humans.  “Modern humans” is a very broad area since it includes Homo sapiens from our origin in Africa through today.  Human evolution is ongoing and identifiable within current populations.

New Ideas and Research contains current research of relevance to this site.  This includes applications of my work to new research.  These explanations will both extend and revise my past work.  These interpretations will be moved to the other sections below as necessary.

Physiology and Pathology is the broadest category.  This area contains many aspects of growth, development, and aging, as well as significant deviations from normal.  This concerns our individual lives or ontogeny.

Evolution  includes an examination of evolution primarily concerned with human phylogeny.  This extends from evolution of eukaryotic organisms to humans.

The Impact of Dehydroepiandrosterone (DHEA) and Testosterone on Humans

This site is intended to disseminate information generated from ongoing work I began in 1984.  Two works were produced in 1985: Evolution of Sociopathy in Western Civilization. A Philosophical Treatise followed by A Theory of the Control of the Ontogeny and Phylogeny of Homo sapiens by the Interaction of Dehydroepiandrosterone and the Amygdala, both copyrighted.  The original focus was narrow.  The scope has rapidly broadened simultaneously with increasing awareness of the explanatory usefulness of the primary ideas.  It is my hypothesis that selection for the androgens, dehydroepiandrosterone and testosterone, is directly linked to human evolution.  Evolution consists of ontogeny and phylogeny.
The information is divided into categories variously dealing with human ontogeny and phylogeny.  Since human ontogeny, the life of the individual, and phylogeny, the life of the species, are interdependent, my divisions are also not exclusive.  These categories are intended only as different entrances to a single explanation of human biology.  There is extensive overlap.  Periodically, new research will be included and discussed below.  (Click on the appropriate category below to access the page.)

Covid-19 Infection and Subsequent Pathology are Caused by low

Dehydroepiandrosterone (DHEA)

(New support: Low DHEA in Covid-19)

(© Copyright 2020-2022, James Michael Howard, Fayetteville, Arkansas, U.S.A.)

New research, 2022, regarding DHEA has been published that supports my hypothesis that Covid-19 is caused by low DHEA: “COVID-19 patients with altered steroid hormone levels are more likely to have higher disease severity,” ( 2022 Jul 30. doi: 10.1007/s12020-022-03140-6.) “DHEA was an independent indicator of the disease severity with COVID-19.”

It is my hypothesis that Covid-19 infection and subsequent pathology are caused by low levels of dehydroepiandrosterone (DHEA) which are affected by aging, testosterone and cortisol levels, and antagonism of DHEA by cortisol as in stress, all of which reduce effects of DHEA (© Copyright 2020, James Michael Howard, Fayetteville, Arkansas, U.S.A.). It is already known that DHEA provides protection from pathogenic viruses. “In this study it was shown that DHEA protects mice against WNV, SVNI and SFV lethal infection.” (Arch Virol. 1991;120(3-4):263-71. doi: 10.1007/BF01310481.) High testosterone levels affect DHEA levels by decreasing available DHEA by reducing conversion of DHEA sulfate to the active form, DHEA, and low testosterone levels reduce intracellular DHEA; both reduce DHEA. This is why high levels of testosterone in males and high levels of testosterone of blacks compared to whites increase Covid-19 virulence, therefore, drugs such as dexamethasone, which is known to reduce testosterone reduce Covid-19 This is why reduced DHEA and testosterone of aging increases Covid-19 virulence.

Regarding the “cytokine storm” in Covid-19 infection, a case may be made that these cytokines are produced by cells / tissues to stimulate DHEA production. Therefore, the reduction in DHEA caused by Covid-19 would cause numerous tissues to produce cytokines to stimulate DHEA. Individuals who do not recover significantly by eventually producing DHEA experience “long covid.”

This is derived from my explanation of human evolution involving DHEA (mammalian evolution) and human evolution involving DHEA and testosterone. I suggest testosterone directly affects levels of DHEA and testosterone is increasing throughout human history and is ongoing. At this time I think testosterone has increased in human populations sufficiently to adversely affect DHEA levels. I suggest this is why human populations are experiencing increases in obesity, type 2 diabetes, cancer, infections, at this time, including Covid-19. (Note: some consider obesity as the cause of the others; obesity is simply the earliest sign.)

Since I think these androgens and their ratio control all aspects of the human life span, I think they are involved in all aspects of normal ontogeny as well as pathology. I suggest this is why Covid-19 has been connected with many pathologies as well as disturbances in cytokines, including “hypertension, diabetes, obesity, COPD, and CVD.”

As I stated above, I think testosterone is increasing with time within populations; an over abundance of testosterone can reduce the effects of DHEA and this is why pandemics are occurring, such as the HIV and others at this time. This is why Covid-19 is occurring at this time and is directly connected to other pathology. They are both caused by low DHEA.

Hormones in Mammalian Evolution,” Rivista di Biologia / Biology Forum 2001; 94: 177-184. If your library does not subscribe to “Rivista … ,” you may find this at: http://anthropogeny.com/Hormones%20in%20Mammalian%20Evolution.htm .

Androgens in Human Evolution, Rivista di Biologia / Biology Forum 2001; 94: 345-362. If your library does not subscribe to Rivista , you may find this at: http://anthropogeny.com/Androgens%20in%20Human%20Evolution.htm where you may also see a chart of testosterone in humans and great apes which directly supports my hypothesis and was reported in the literature 2 years later.