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Unit 1
Origin and History of Vitamins
Introduction Origin and History of Vitamins What are Vitamins? How Are Vitamins classified? Recommended Daily Allowances Homework Assignment
Introduction
Welcome to Lesson 1 of Help Yourself to Health: Vitamin Basics. We have all gazed at the cereal box label during breakfast when we were children and wondered what words like vitamins, folic acid and riboflavin meant. We wondered why our parents insisted that we drink plenty of milk, eat red meat, and finish our green vegetables.
Of course, we now realize that the information on the cereal box and the advice of our parents were both related to vitamins. In this class, we shall explore the little understood world of vitamins and why they are necessary to human health.
During my graduate studies in Pharmacy, I devoted over six months to the study of vitamins. We will try to cover much of the same ground in just five weeks. When you finish this course, you won't be qualified to set up shop as a pharmacist, but you will know how to read and understand the cereal box and other food labels. Let's get started!
In this Lesson we shall cover the following topics:
Please note: The information provided in this course is intended for general reference and educational purposes only. It should not be construed as medical advice and it is not a substitute for medical treatment. Always seek guidance from your physician or health care provider before starting any treatment with vitamins.
Origin and History of Vitamins
Our brief journey into the history of vitamins starts almost 3500 years ago, when the ancient Egyptians discovered that night blindness could be treated with certain foods. Despite this early wisdom, much of the ancient knowledge gathered about vitamins was forgotten down through the centuries. During the Middle Ages, diseases were commonly attributed to witchcraft, bad air, angry gods, spontaneous affilictions and so forth.
It is primarily because of comparatively recent advances in the work of molecular biologists that we today have a good understanding of vitamins and other nutrients.
One of the major milestone in nutritional medicine occurred in 1747, when Scottish surgeon James Lind discovered an unknown nutrient that we today call Vitamin C. He found that scurvy, a widely reported disease characterized by spontaneous bleeding, loose teeth, aching joints and lack of energy, could be prevented by taking citrus foods. Unfortunately, his discovery was largely ignored, and over the next forty years, thousands of people died from scurvy.
In the 1860s, Louis Pasteur discovered that microscopic organisms caused many diseases. His discoveries prompted further research into the curativeand preventative properties of vitamins.
As recently as the early 1900s, numerous diseases such as beriberi and pellagra were still regarded as infectious diseases rather than nutritional deficiencies.
In 1911, the first major shift in perception of nutrition occurred after the discovery of vitamins by a Polish Chemist, Casimir Funk, at the Lister Institute in London.
Between the 1920s and 1930s, it became clear that administering small amounts of vitamins could easily cure persons affilicted with severe deficiency diseases.
The discovery of Vitamin C earned the Nobel Prize in Medicinefor famed Hungarian researcher Dr. Albert Szent-Gyorgyi in 1937.
From the initial discovery of vitamins in 1911 through the 1950s, nearly all physicians around the world based their studies and diagnoses on vitamin deficiencies. During the 1940s and 1950s, a number of researchers began to lay the foundation for a new erain vitamins. Much of our present-day knowledge evolved from theworks of these scientists.
The future of nutritional medicine holds wondrous possibilities for mankind, and as our knowledge of vitamins and other nutrients expands further, we will no doubt discover that vitamins have even greater value and utility than we presently imagine.
Our view and vision of nutrition and vitamins may be limited by what we know today, but we should leave our door open for what we have not yet discovered. In fact, it is quite likely that some vitamins have yet to be discovered.
What are Vitamins?
Before we delve into vitamins, we must first understand the concept of nutrients. To function, the human body must have nutrients. The nutrients known to be essential for human well being are: proteins, carbohydrates, fats and oils, minerals, vitamins, and water.
Vitamins are a group of substances that are essential for normal metabolism, growth and development, and regulation of cell function. The word vitamin derives from the words vital and amine. Vitamins are organic (that is, carbon containing) molecules which mainly act as a catalysts in our body
All naturally occuring vitamins are organic food substances that are found only in living things; that is, plants and animals. With a few notable exceptions, the human body cannot manufacture or synthesize vitamins on its own. Vitamins must be supplied in the diet or in dietary supplements.
Vitamins help to regulate the metabolism. They also help convert fat and carbohydrates into energy and assist in the formation of healthy bones and tissues. In addition, vitamins provide vitality and general well being.
Vitamins can be used to effectively treat and cure nutritional based deficiencies. Although vitamins do not prevent or cure other types of invasive diseases such as cancer, affilictions related to aging, or biological infections, a diet that supplies the proper balance of essential vitamins and nutrients can help fortify the immune system and thus provide some beneficial protection against such diseases. It is likely that future discoveries will shed new light on vitamins and their important role in human disease and aging.
It is important to understand that vitamins cannot replace food. In fact, vitamins cannot be assimilated without ingesting food. That is why doctors and advocates of natural nutrition stress that vitamins must be taken with meals. Vitamins work together with enzymes, co- factors and other substances in the digestive tract. As I stated earlier, the body cannot create vitamin molecules itself, so these molecules must come through food that we eat.
As a general rule, vitamins are destroyed by heat, exposure to air, sunlight, and oxidizing conditions. Improper storage conditions can allow mold growth. If mixed into other foods, vitamins should always be consumed within a couple of days at most.
Researchers have found that the requirement of vitamins varies from one person to another, and that psychological stress can rapidly delete the body's vitamin reserves. With a few notable exceptions, it is better to have an excess of vitamins in the body than to be deficient. Vitamin supplements are readily available at health food stores, pharmacies and grocery stores, and are usually inexpensive.
How Are Vitamins classified?
Each vitamin plays a specific role in the human body. In many cases, vitamins must interact with other vitamins to function properly, and a lack or excess of any one of then can disturb the assimilation of another vitamins. Thus, taking multi-vitamin formulas where there is too much of one vitamin and too little of anothers can have less than desirable results. Poorly balanced multi-vitamin formulas can even cause vitamin deficiencies!
Vitamins are classified according to:
- Toxicity, and
- Solubility (water or fat)
This classification is rather complex and is based on the level of toxicity of different vitamins. Please bear in mind that vitamins are not toxic, although an overdose of certain vitamins can have adverse health effects.
Toxic vitamins have a therapeutic index of 20 or less and include Vitamin A (retinal, retinal, and retinoic acid) and Vitamin D.
Non-toxic vitamins have a therapeutic index of 20 or more and include all vitamins other than A and D.
Classification based on Solubility:
This is the most widely accepted theory on classifying vitamins. It divides vitamins into two sets: vitamins which are soluble in water and those which are fat-soluble.
There are 13 vitamins presently known to science which are required by the human body, and they are classified as follows:
Water Soluble:Because the above vitamins are water soluble, they are not stored for very long in the body. Foods which supply these vitamins should be eaten in adequate amounts every day.
Vitamin B1 (Thiamine)
Vitamin B3 (Niacin)
Folate
Vitamin B12
Pantothenic acid
Biotin.
Vitamin C (ascorbic acid)
Fat Soluble:The foregoing vitamins are digested and absorbed with the help of fats occuring naturally in the diet. Fat soluble vitamins can be stored in the body for long periods of time. They are stored mostly in the fatty tissues and in the liver. Hence, supplementations are not required as frequently as with water-soluble vitamins. However, in emotionally stressful conditions, supplementation becomes important.
Vitamin A
Vitamin D
Vitamin E
Vitamin K
Because fat soluble vitamins are stored in the body, it is possible to overdose by taking too much of these vitamins. Care must be taken to ensure that safe dosage levels are not exceeded.
In upcoming lessons, we will examine each of these 13 vitamins in greater detail.
Where do vitamins come from and how much of each vitamin is recommended? The two primary sources of vitamins for human consumption are in plantsand in animal tissues. Unfortunately, the amount of vitamin that onecan expect to derived from a given source can vary, depending on a variety of circumstances. For example, in plants, the vitamin yield will vary depending on:
- How the plant is harvested and processed. Often, nutrients are
leached out of the plant during processing and the "food" that results has
little or no nutritional value.
- The part of the plant being processed will affect vitamin levels to
a significant degree.
- The species of the plant will also affect vitamin content.
Some hybrid plants that produce a higher yield per acre and can be
harvested sooner are more profitable for farmers yet exhibit markedly
reduced vitamin content.
- Liver
- Kidney
Recommended Daily Allowances
The best way to ensure that your body gets the daily requirement of vitamins is to eat a balanced diet, which contains a variety of foods. The daily recommended levels of vitamins are often referred as the RDA or Recommended Daily Allowances.
RDA are defined as the levels of intake of nutrients that, on the basis of current scientific knowledge, the Food and Nutrition Board regard as adequate to meet the known nutritional needs of most healthy people.However, determing RDA for each vitamin is not that simple. Specific requirements may vary depending on age, gender, and a multitude of other factors such as pregnancy, stress, work and sleep habits, presence of disease or degenerative conditions, and other health and lifestyle considerations. We will learn more about this in upcoming lessons.
Homework Assignment
Our first week's homework assignment is easy and will take just a few minutes of time. Introduce yourself and briefly explain why you are taking this course and what you hope to gain from it. Post your work on the class bulletin board.
Until next week, best wishes!
Indrajit Sen
Instructor
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