Shakespeare was correct when he wrote, "One man's meat is another man's poison." (in Walsh, 2000) For instance, "some of us are genetically suited for a vegetable-based diet and others are not. Some people can satisfy their nutritional needs by diet alone and others must have nutritional supplements to overcome genetic aberrations" (Walsh, 2000). On the other hand, serious health problems may develop if a person overconsumes nutrients. After having studied the biochemical individuality of 10,000 persons, Walsh came to a decision that the greatest trouble is typically caused by nutrients that are stored in exceeding amounts, rather than by the lack of them .
Due to genetic dissimilarity in the way human body processes foods, vast majority of people are to a certain extent deficient in some nutrients and overloaded in others. Even following an ideal diet, many people have some nutrients at extremely low levels, much lower than the concepts of adequate nutrition and optimum nutrition require. The nutrients which are stored in exceeding amounts in one's body should be avoided by them, keeping from certain kinds of food and vitamins. The most widespread nutrients in overload are following substances: iron, copper, folic acid, manganese, choline, a variety of fatty acids and methionine. But this statement does not contradict to a fact that some people can lack these nutrients. As we know there is a number of manufacturers who produce food supplements and advertise an idea of 'healthy nutrition in a single package'. Being familiar with the issue, I can say that it looks like trying to determine an ideal clothes size for all people. The term 'biochemical individuality' point at individual needs, and multiple nutrients are extremely indiscriminate and may cause to a great harm as well as improve one's health. Doctor Walsh also indicates that he has systemized biochemical types. "After studying the metabolic status of thousands of persons, I discovered that lab chemistry could be predicted with good accuracy based on an individual's traits, symptoms, and family history" (Walsh, 2000). He developed a system of types and classes, which had personal information (case history) as its basis. The vast majority of his clients were divided into 26 types different in metabolism, neurotransmitter production, glucose rates and 'genetic' history.
Dr. Williams as a dietician and biologist also made a contribution to the development of the viewpoints regarding biochemical origin of ailment with the progress of the theory of biochemical individuality. He explained physiological differences between people and how they linked to individual reactions to the environmental irritators. At the beginning of 1980s the area of biochemical individuality got its 'fashion' between the sciences of biology, chemistry and physiology as a result of the advancement made in theorizing molecular biology of the genetic material. So-called Human Genome plan designed a major worldwide obligation of scientists to 'decode' the genetic information of life by observing a chain of human chromosomes. As this issue has extended from biochemical institutions around the world, its suggestions have been innovatory in terms of how science had previously viewed genes and chromosomes. The DNA is not seen as a rigid structure any longer. Indeed, as Bishop and Waldholz highlighted in