Read an Excerpt
A rags to riches story:
From a vitamin looking for a disease ...
To the shady lady of vitamins ...
To the master antioxidant and
Good fairies attended every phase of the advent and early history of vitamin E.
If good fairies were indeed helping, they chose some really good researchers. The year was 1922 and the place the University of California at Berkeley. Herbert A Evans, a young research physician specializing in embryology, and his assistant, Katharine S. Bishop, were feeding their laboratory rats a special semipurified diet. This diet was developed by two groups of pioneer nutritionists of that era, Drs. Thomas B. Osbome and Lafayette B. Mendel and Drs. Henry A. Mattil and R. E. Conklin.
Instead of whole foods, sermipurified diets contain mostly ingredients isolated in pure form and only a small amount of whole food. For example, the diet used by Evans and Bishop contained starch to provide carbohydrates, milk casein for protein, lard and butter for fat, brewer's yeast for micronutrients including some vitamins, and salts for minerals. Unlike semipurified diets, purified diets do not contain whole foods--only pure ingredients.
Semipurified and purified diets have been great tools for nutrition research. By excluding a nutrient from the diet, researchers can evaluate the effect of its absence on survival, growth, andhealth. By introducing increasing amounts of the nutrient in the diet, they can determine what is the minimum amount required for survival, good growth, and health. And they can keep increasing the amount until they find the level that causes toxicity and death.
Drs. Evans and Bishop saw their rats grow well. The females, however, would become pregnant, but their pregnancies would not go to term. Their pups would die in the womb and be resorbed or be born dead. When they supplemented the rats' diet with fresh lettuce and, in later studies, with wheat germ, healthy pups were born. They figured that something was missing from the diet but did not have the foggiest idea what it was. The mystery ingredient was dubbed as Factor X.
Drs. Evans and Bishop relayed their observation to Professor Mendel, the leading developer of the diet. His response was vintage professorial; uncovering the mystery of Factor X, he suggested, would make a splendid project for a graduate student--assign one! The lucky fellow was Karl E. Mason.
Vitamin E is born: Continuing their research, Drs. Evans and Bishop found that Factor X was in the lipid extract of lettuce. This was a clear clue that it was a fat-soluble substance. Mason found that deficiency of this factor caused damaging lesions in the testis (male reproductive gland) and uterus of rats. They figured that Factor X was really important and deserved a real name. This was the era when vitamins were being discovered. Factor X appeared to have the attributes of a vitamin.
Unbeknownst to Drs. Evans and Bishop, Dr. Barnett Sure at the University of Arkansas observed independently that a missing factor in the diet was making male rats sterile. He proposed in 1924, one year earlier than Dr. Evans, the name vitamin E. The letters A, B, and C were already taken, and D was spoken for.
Also Dr. Matill and his group at the University of Iowa described briefly an atrophy (poor growth) of the testis before Dr. Mason had.
Sure and Matill. deserve major credit for their contribution to the discovery of vitamin E.
Evans proposed one year later the name vitamin E for the same reasons as Dr. Sure. "We have adopted the letter E as the next serial alphabetical designation, the antirrachitic vitamin now being known as vitamin D," Dr. Evans wrote in 1925.
THE FRUSTRATING DECADE (1925-1935): A VITAMIN LOOKING FOR A DISEASE
The excitement from the discovery of vitamin E did not last very long. It was soon overshadowed by the slow progress in figuring out its function.
Scientists were seriously hampered in their research. They did not know whether vitamin E was a single compound or what its structure was. And there was no pure or even concentrated vitamin E to use in their studies. Wheat germ was a good source-but how much was there? There was no method to analyze for vitamin E or to measure its potency!
If vitamin E is essential for reproduction, some reasoned, then it must be able to cure problems of fertility and reproduction. And sure enough it would help the sex drive! The initial excitement of veterinarians and clinicians (and many other people) turned out to be a major disappointment. And the stories about sex drive made good fodder for jokes--not the impetus for good science! The labels "sex vitamin" and "shady lady of vitamins" haunted vitamin E for decades.
In retrospect, the small progress made was important! Scientists uncovered the devastating effects of vitamin E deficiency on the muscles and the nervous system (including the brain). They also described the conditions of
- Paralysis of baby rats suckling vitamin E-deficient mothers
- Chicken encephalomalacia, which is a softening, almost rotting of the brain that results in death of chickens
- Muscular dystrophy in guinea pigs and rabbits
It was also during this decade that scientists began to suspect that vitamin E acted as an antioxidant!
My studies concerned a description of the process of degeneration of the germinal epithelium of the male rat, which is preventable, but not repairable. (emphasis added)
We have learned since then that vitamin E deficiency may go unnoticed for years without clinical symptoms. The story of Vicki the elephant in chapter 5 is a classic example of how unnoticed muscle and nerve damage can pile up. We also learned that depleted tissues get replenished slowly and the nerve tissue even more slowly. When the clinical symptoms appear it is usually too late for repair!