Take the Pledge. The discovery of vitamin A and the history of its application in the field of human nutrition is a story of bravery and brilliance, one that represents a marriage of the best of scientific inquiry with worldwide cultural traditions; and the suborning of that knowledge to the dictates of the food industry provides a sad lesson in the use of power and influence to obfuscate the truth. A key player in this fascinating story is Weston A.
Price, who discovered that the diets of healthy traditional peoples contained at least ten times as much vitamin A as the American diet of his day. His work revealed that vitamin A is one of several fat-soluble activators present only in animal fats and necessary for the assimilation of minerals in the diet. He noted that the foods held sacred by the peoples he studied, such as spring butter, fish eggs and shark liver, were exceptionally rich in vitamin A.
All traditional cultures recognized that certain foods were necessary to prevent blindness. In his pioneering work, Nutrition and Physical Degeneration, Weston Price tells the story of a prospector who, while crossing a high plateau in the Rocky Mountains, went blind with xerophthalmia, due to a lack of vitamin A. Several years previous to the travels of Weston Price, scientists had discovered that the richest source of vitamin A in the entire animal body is that of the retina and the tissues in back of the eyes.
Many cultures used liver, another excellent source of vitamin A, for various types of blindness. The Egyptians described this cure at least years ago.
Similar practices have been described in 18th-century Russia, rural Java in and among the inhabitants of Newfoundland in Other cultures used the liver of shark.
Hippocrates BC prescribed liver soaked in honey for blindness in malnourished children. Assyrian texts dating from BC and Chinese medical writings from the 7th century AD both call for the use of liver in the treatment of night blindness. A 12th-century Hebrew treatise recommends pressing goat liver to the eyes, followed by eating of the liver.
Who does not at night see right Eats the liver of goat He will then see better at night. Night blindness was a recurring problem among sailors on long voyages but by the advent of the great European navies, the wisdom of traditional liver therapy was largely ignored.
It took brave dedication to the scientific method to confirm the validity of the ancient treatments. Before his departure from Vienna, several physicians had asked Schwartz to test the old folk remedy of boiled ox liver against night blindness.
On the voyage, 75 of the men developed the condition. Every evening when dusk came, they lost their vision and had to be led about like the blind.
Schwartz fed them ox or pork liver and found that the night vision in all of the afflicted was restored.
He was The use of vitamin-A-rich foods for tuberculosis had not yet been discovered. In , the Japanese physician M.
He treated the children with liver and also cod liver oil with excellent results. In fact, he found that cod liver oil was even more effective than liver in restoring visual function. Indeed, in most cases, the effect is so rapid that by evening the children with night blindness are already dancing around briskly, to the joy of their mothers.
At the end of the First World War, a physician named Bloch discovered that a diet containing whole milk, butter, eggs and cod liver oil cured night blindness and keratomalacia. In one important experiment, Bloch compared the results when he fed one group of children whole milk and the other margarine as the only fat.
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Half of the margarine-fed children developed corneal problems while the children receiving butterfat and cod liver oil remained healthy. The actual discovery of vitamin A is credited to a researcher named E. He was curious why cows fed wheat did not thrive, became blind and gave birth to dead calves, while those fed yellow corn had no health problems.
The year was and by this time, scientists were able to determine the levels of protein, carbohydrate, fat and minerals in food. McCollum wondered whether the wheat contained a toxic substance, or whether there was something lacking in the wheat that was present in yellow maize?
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In order to solve the puzzle, McCollum hit upon the idea of using small animals like mice or rats rather than cows for nutrition experiments—they ate less, took up less space, reproduced rapidly and could be given controlled diets. Like many good ideas, this one met with considerable opposition.
He discovered that rats fed pure protein, pure skim milk, sugar, minerals and lard or olive oil for fat failed to grow. When he added butterfat or an extract of egg yolk to their diets, their health was restored.
He discovered a fat-soluble factor in certain foods that was essential for growth and survival. Continued experiments helped scientists determine that vitamin A was colorless, but often associated in foods with beta-carotene, which was yellow.
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In the s, researchers discovered that vitamin A is formed by the conversion of beta-carotenes in the intestinal mucosa of animals and humans. The scientific term for vitamin A is retinol, because of its presence in the retina of the eye. The role of retinol in vision was elucidated by a number of brilliant scientists, beginning in with a German, W. Kuhne, who discovered that the purple retinas from dark-adapted frogs turned yellow when exposed to light. The purple color is restored in a complex biochemical cycle involving vitamin A, which makes vision possible.
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Other scientists demonstrated the role of vitamin A in cell differentiation, bone development, reproduction and immune system function. Weston Price confirmed the value of vitamin A in traditional diets during his studies of indigenous peoples carried out during the s and s. Due to the outstanding scientific work of these and many other researchers, the administration of cod liver oil to growing children—a tradition found among Arctic peoples such as the Scandanivians and Eskimos—became standard practice until after the Second World War.
Ironically, as Americans have stopped giving cod liver oil to their children, programs to administer vitamin A to children in Africa and Asia have had astonishing success in preventing blindness and infectious disease. This vitamin-A-treatment program was the brainchild of yet another brave researcher, Alfred Sommer, an ophthalmologist at Johns Hopkins University, who patiently lobbied for an international program after observing the wonderful effects of vitamin-A supplementation in Indonesia and Nepal.
In recent decades, much vitamin-A research has focussed on its role in preventing cancer, and its use in combination with nontoxic therapies in the treatment of cancer.
Unfortunately, research on the anticarcinogenic properties of vitamin A has not been widely adopted. Perhaps the most tragic example is Dr. Max Gerson, who treated many cases of terminal cancer with excellent results using raw liver juice, a rich source of vitamin A. In , he testified before a US congressional committee on the success of his treatment, but it was subsequently ignored.
Kanematsu Sigiura of the Sloan Kettering Institute published the results of studies on mammary tumors in mice using high doses of vitamin A and a derivative of seeds called laetrile. He observed complete regression of all the tumors in a total of five mice. Sigiura has never observed complete regression of these tumors in all his cosmic experience with other chemotherapeutic agents.
While the ongoing process of research into vitamin A and its effects is a boon to children and adults throughout the world, modern agriculture and food processing conglomerates gain nothing from this knowledge.
Confinement farming practices effectively prevent vitamin A from incorporation into animal foods and the processing industry would rather use vegetable oils than animal fats.
Some vegetable oils contain carotenes but they do not contain true vitamin A. Only animal fats contain vitamin A and vitamin A is present in large amounts only when the animals have a source of carotenes or vitamin A in the diet, such as green pasture, insects and fish meal. Unfortunately, the vast majority of popular books on nutrition insist that humans can obtain vitamin A from fruits and vegetables.
Even worse, FDA regulations allow food processors to label carotenes as vitamin A. The label for a can of tomatoes says that tomatoes contain vitamin A, even though the only source of true vitamin A in the tomatoes is the microscopic insect parts. The food industry, and the lowfat school of nutrition that the industry has spawned, benefit greatly from the fact that the public has only vague notions about vitamin A. In fact, most of the foods that provide large amounts of vitamin A—butter, egg yolks, liver, organ meats and shellfish—have been subject to intense demonization.
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Under optimal conditions, humans can indeed convert carotenes to vitamin A. This occurs in the upper intestinal tract by the action of bile salts and fat-splitting enzymes. Of the entire family of carotenes, beta-carotene is most easily converted to vitamin A.
Early studies indicated an equivalency of of beta-carotene to retinol. In other words, four units of beta-carotene were needed to produce one unit of vitamin A.
This ratio was later revised to and recent research suggests an even higher ratio.
J. Richard Steffy
But the transformation of carotene to retinol is rarely optimal. Diabetics and those with poor thyroid function, a group that could well include at least half the adult US population, cannot make the conversion.
Children make the conversion very poorly and infants not at all — they must obtain their precious stores of vitamin A from animal fats 6 — yet the low-fat diet is often recommended for children.
Carotenes are converted by the action of bile salts, and very little bile reaches the intestine when a meal is low in fat. The epicure who puts butter on his vegetables and adds cream to his vegetable soup is wiser than he knows. Butterfat stimulates the secretion of bile needed to convert carotenes from vegetables into vitamin A, and at the same time supplies very easily absorbed true vitamin A. Polyunsaturated oils also stimulate the secretion of bile salts but can cause rapid destruction of carotene unless antioxidants are present.
It is very unwise, therefore, to depend on plant sources for vitamin A. This vital nutrient is needed for the growth and repair of body tissues; it helps protect mucous membranes of the mouth, nose, throat and lungs; it prompts the secretion of gastric juices necessary for proper digestion of protein; it helps to build strong bones and teeth and rich blood; it is essential for good eyesight; it aids in the production of RNA; and contributes to the health of the immune system.
Vitamin-A deficiency in pregnant mothers results in offspring with eye defects, displaced kidneys, harelip, cleft palate and abnormalities of the heart and larger blood vessels.
Vitamin A stores are rapidly depleted during exercise, fever and periods of stress. Even people who can efficiently convert carotenes to vitamin A cannot quickly and adequately replenish vitamin A stores from plant foods.
Foods high in vitamin A are especially important for diabetics and those suffering from thyroid conditions. In fact, the thyroid gland requires more vitamin A than the other glands, and cannot function without it. Weston Price considered the fat-soluble vitamins, especially vitamin A, to be the catalysts on which all other biological processes depend.
His research demonstrated that generous amounts of vitamin A insure healthy reproduction and offspring with attractive wide faces, straight teeth and strong sturdy bodies. He discovered that healthy native peoples especially value vitamin-A-rich foods for growing children and pregnant mothers. The tenfold disparity that Price discovered between indigenous diets and the American diet in the s is almost certainly greater today as Americans have forsworn butter and cod liver oil for empty, processed polyunsaturates.
In Third World communities that have come into contact with the West, vitamin-A deficiencies are widespread and contribute to high infant mortality, blindness, stunting, bone deformities and susceptibility to infection. Scarcity of good quality dairy products, a rejection of organ meats as old fashioned or unhealthful, and a substitution of vegetable oil for animal fat in cooking all contribute to the physical degeneration and suffering of Third World peoples.
Supplies of vitamin A are so vital to the human organism that mankind is able to store large quantities of it in the liver and other organs. Thus it is possible for an adult to subsist on a fat-free diet for a considerable period of time before overt symptoms of deficiency appear.
But during times of stress, vitamin A stores are rapidly depleted. Strenuous physical exercise, periods of physical growth, pregnancy, lactation and infection are stresses that quickly deplete vitamin A stores.