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Biochemical Individuality: The Key to Understanding What Shapes Your Health

Roger J. Williams, PhD.. Introduction to he 1988 edition by Jeffrey Bland PhD


What are the characteristics of a "classic book"? Is it the timelessness of the message? The insight which spurred the development of a field? The contribution to a new way of thinking that significantly improved the state of society? Or the ability to see the "obvious" in a way that had never been seen before and so well communicated?

The book Biochemical Individiuality, authored by the late world-renowned biochemist Roger Williams, Ph.D., first published in 1956, fulfills all of these characteristics. It is a book that should be on the bookshelf of all students and practitioners of modern molecular medicine. It is with great admiration and respect that I have the privilege of writing the introduction to the republication of this timeless work.

Molecular medicine was a term used by two-time Nobel laureate in chemistry and peace Linus Pauling, Ph.D., in his landmark article on the mechanism of production of sickle cell anemia published in 1949. [1] It defined a new perspective on the origin of disease based upon the recognition that specific mutations of the genes can create an altered "molecular environment" and therefore the modified physiological function associated with specific diseases.

Dr. Williams contributed to the evolution of the understanding of the molecular origin of disease with the development of the concept of biochemical individuality. He described anatomical and physiological variations among people and how they related to their individual responses to the environment. He was the first to gain recognition for the term "biochemical individuality" and how this related to differing nutritional needs for optimal function among different people. He pointed out that even identical twins could be different in their needs for optimal function based upon the fact that they developed in different environments in utero. Although identical twins share the same genes, their differing nutrition and developmental environments can result in different expression of the genes as they grow older.

In the 1980s the field of biochemical individuality became fashionable within science as a consequence of the progress made in understanding the molecular biology of the gene. The Human Genome project represented a major international commitment of scientists to understand the genetic code of life by sequencing the human chromosomes. As this story has unfolded from laboratories around the world, its implications have been revolutionary in terms of how medicine views genes and their function. The genetic structure is no longer seen as "rigid" as previously considered. Rather, as Bishop and Waldholz pointed out in their book Genome, "aberrant genes do not, in and of themselves, cause disease. By and large their impact on an individual's health is minimal until the person is plunged into a harmful environment. . . . The list of common diseases which has its roots in this genetic soil is growing almost daily. . . . How many human ills will be added to the list is unknown, although some contend that almost every disorder compromising a full and healthy four score and ten years of life can be traced in one way or another to this genetic variability" (Simon and Schuster, New York, 1990).

The first major breakthrough that resulted in this revolutionary change in thinking about the origin of disease was the recognition that we are much more different biochemically than was previously acknowledged.[2] Dr. Williams in Biochemical Individuality pioneered this revolution in thinking forty years ago. Genetic polymorphism is the term which has emerged in the past decade to describe this variation in function surrounding a specific genetic trait.

The second major breakthrough in thinking made by Dr. Williams is the recognition that nutritional status can influence the expression of genetic characteristics.[3] Once again Dr. Williams foresaw this important concept in Biochemical Individuality and set in motion research and discoveries over the past four decades that have transformed medicine. It is now well recognized that our genotype gets transformed into our phenotype as a consequence of nutritional, lifestyle and environmental factors which are important in determining our health patterns.

In 1976 Dr. Williams and his colleague Donald R. Davis, Ph.D., co-authored a paper entitled "Potentially useful criteria for judging nutritional adequacy" in which they provided observations about how nutritional status can influence the functional expression of the genes. They pointed out that phenotypic characteristics such as voluntary consumption of food, sleeping time after anesthesia, weight gains after surgery, heating time after surgery, hair growth after clipping, voluntary sugar consumption and recovery time after poisoning could all be influenced by nutritional influence on gene expression.[4]

The concept of biochemical individuality has become part of most contemporary clinical and experimental medical and nutritional research. People are now known to fit into personally unique biochemical profiles based upon their own genetic structure, nutrition and environment.[5] There is no such thing as a truly "normal" individual-meaning average. We are all biochemically unique and need to be dealt with as such. The Recommended Dietary Allowances (RDAs) which were developed by the Food and Nutrition Board of the National Research Council to establish the nutritional needs of "practically all healthy people" were not based upon the more recent information concerning the range of biochemical individuality among individuals. The RDAs that describe "normal" nutritional needs have questionable relevancy to the concept of optimal nutrition based upon individual needs. The contributions of Dr. Williams have opened the door for personally tailored nutritional and medical interventions that take biochemical individuality into account.

Some of the world's foremost nutrition and medical researchers are now actively involved in developing a better understanding of the field which Dr. Williams pioneered. Rucker and Tinker from the University of California at Davis, Department of Nutrition, have described the role of nutrition in gene expression and its relationship to biochemical individuality as "a fertile field for the application of molecular biology."[6] It is now well known that significant biochemical diversity occurs in such physiological functions as the ability the individual to detoxify both exogenous and endogenous s stances, the control of blood cholesterol, the metabolism of the potentially harmful amino acid homocysteine, and the response certain cancer genes to the diet and environment. These are all examples of how nutritional status can influence disease patterns based upon biochemical individuality.

Dr. Williams coined the term "genetotrophic disease" to describe diseases which resulted from genetically determined nutritional metabolic needs not being met by the individual and which result in poor gene expression. Motulsky has recently argued that many the common degenerative diseases are the result of the imbalance nutritional intake with genetically determined needs for good health.[7]

The genetic concept with which most nutrition and medical searchers grew up intellectually before the contribution of Dr. Williams was that of Gregor Mendel. His concept of dominant recessive genetic characteristics gave us the belief that our characteristics are "locked in stone" when the sperm meets the egg. Dr. Williams opened the eyes of the research communities that expression of genes and therefore phenotypic function was modifiable through altered diet and nutritional status. He pointed out human biochemical variation in function was much greater than nutrition and medicine recognized prior to his publications.[8] Simopoulos has stated that "of all the recent scientific advances contributing to our understanding of the role of nutrition in disease prevention and the variability in human nutrient needs, the recognition of genetic variation as a contributing factor must rank am the highest."[9]

Dr. Williams made this complicated story easy to understand and compelling to health scientists and the general public alike. His clarity of thought and language helped open up this field which been dominated by Mendelian thinking for nearly one hundred years before the publication of Biochemical Individuality. In one of lectures at which I was in attendance he responded to an inquiry as to why the RDAs were not sufficient to define a person's nutritional needs with the simple insight, "Nutrition is for real people. Statistical humans are of little interest."

It is very timely that Biochemical Individuality is being reprinted over forty years after its initial publication, and that it is even more timely today than at the time of its original publication. By all definitions, Biochemical Individuality fulfills the definition of "a classic" and should have an honored place among the principal reference books of anyone interested in health and nutrition.

Jeffrey S. Bland, Ph.D
HealthComm International, Inc
Gig Harbor, WA


1. Pauling L, Itano HA. Sickle cell anemia: a molecular disease. Science 1949; 110:543-548:
2. Motulsky AG. The 1985 Nobel Prize in physiology and medicine. Science 1986; 231:126-127.
3. Holtzman NA. Genetic variation in nutritional requirements and susceptibility to disease: policy implications. Am J Clin Nutrition 1988 48:1510-1516.
4. Davis DR, Williams RJ. Potentially useful criteria for judging nutritional adequacy. Am J Clin Nutrition 1976; 29:710-715.
5. Robertson EA, Young DS. Biochemical individuality and the recognition of personal profiles with a computer. Clin Chemistry 1980; 26:30-36.
6. Rucker R, Tinker D. The role of nutrition in gene expression: A fertile field for the application of molecular biology. J Nutr 1986; 116:177-189
7. Motulsky A. Nutrition and genetic susceptibility to common diseases. Am J Clin Nutrition 1992; 55:1244S-1245S.
8. Motulsky A. Human genetic variation and nutrition. Am J Clin Nutrition 1987; 45:1108-1113.
9. Simopoulos AP. Genetic variation and nutrition. Nutrition Today 1995 30: 157-167.

From the back cover of the 1998 edition:

Biochemical Individuality explains why:

  • some of us are better at detoxifying drugs and chemicals

  • the harmful amino acid homocysteine may or may not cause heart disease

  • cancer genes respond in different ways to diet and environment

  • some people are alcoholics or diabetics

  • low fat diets cause some people to gain weight

  • one person needs higher levels of a nutrient than another to be health

Biochemical Individuality: The key to understanding what shapes your health
Roger J. Williams, Ph.D.
Keats Publishing, New Canaan, CT; 1998.
ISBN: 0-87983-893-0
Copyrights: 1956, 1984. Printings: John Wiley & Sons: 1956, 1963; University of Texas Press: seven printings between 1969-1988.


Cover photo of the book, "Biochemical Individuality", by Roger J. Williams, Ph.D

Biochemical Individuality (1998) is available from the following online booksellers:

A1 Books,,,, Barnes &, Booksamillion, and

Cover photo of the book, "Evaluate Your Own Biochemical Individuality", by Jeffrey Bland, Ph.D.

Evaluate Your Own Biochemical Individuality, by Jeffrey Bland, Ph.D. (1987) is out of print but may still be obtained through Barnes &












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