USANA Nutritionals

What Is a Vitamin?

Vitamins are essentially substances made by plants with the help of sunlight or by lower forms of life such as bacteria; in a few case, vitamins can also be created by animals or the human body. They are always combinations of several chemical elements.

Most of our vitamins come from plants, and interestingly, the amount of a vitamin found in a given plant is always the same because the plant always makes just the right amount it needs to stay alive. For example, the average-size orange usually has about 85 mg of vitamin C. vitamins found in animal products, such as eggs, are by-products of the plants ingested by the animal or were created by bacteria.

Over the years, scientists have developed three criteria by which a substance can be defined as a vitamin. If one of the three criteria is not satisfied, the substance in question is not considered a vitamin in the strictest scientific sense:

1. A vitamin is a nutrient required in small amounts for normal body function. With few exceptions, vitamins are not made in the body and must be supplied from an outside source. Even in those few circumstances where vitamins are made in the body, the process generally involves an important ingredient from outside the body, such as the bacteria normally found in our intestines. These bacteria are part of the normal flora that find their way into our body and reside within each of us.
2. A vitamin must be an organic chemical; that is, every vitamin has at least one carbon atom in its molecular structure. This automatically excludes minerals and other non-carbon-containing substances.
3. There is a specific set of symptoms or a specific disease associated with a deficiency of each vitamin, and it can be corrected by taking the appropriate amount of that vitamin.

It is unfortunate that advocates of vitamin treatments for illness have used the work vitamin improperly. Many of the proposed treatments involve doses of vitamins so far beyond the amounts required for normal nutrition that they are, in fact, no longer vitamins but drugs. Also, many treatments involve substances that do not meet the established criteria for vitamins: pseudo-vitamins. These include PABA, choline, inositol, and other substances that have been labeled vitamins to simply lend them public credibility.

Pressure from the United States Food and Drug Administration has forced the elimination of most pseudo-vitamins from multivitamin products. Despite the fact that these substances are either abundant in the food we eat or are not needed for daily function, they are still available for purchase in any health food store or vitamin center.

How Vitamins Work

Vitamins are chemical components in the complex machine that we call the human body. Each vitamin fits into a different part of the machine, and all of them are necessary for normal body function.

Chemists would call most vitamins cofactors (or catalysts). A cofactor is a substance that helps chemical reactions occur (usually more rapidly) but is not a primary ingredient in the reaction. A rough analogy is the oil in your car’s crankcase: Although it is an essential ingredient to your automobile engine, it is not a major ingredient in the chemical reaction that makes the engine work. The major ingredients are gasoline, oxygen, and electrical spark. The oil helps this chemical reaction reach maximum efficient by keeping all of the moving parts of your engine running as smoothly and friction free as possible.

Vitamins perform the same function in the body. For example:

• Vitamin B1 (thiamin) is a cofactor in the series of chemical reactions that burn carbohydrates (sugars) in the body. Without thiamin, you would not be able to provide sufficient energy for body functions.
• Vitamin B2 (riboflavin) serves as a cofactor in many chemical reactions involving the release of energy from body proteins. For this reason, your riboflavin needs are directly related to the amount of energy you use each day.
• Folic acid serves as a cofactor in one of the chemical reactions that are basic to normal cell division I your body. Cell division is essential to many basic functions, including the replacement of worn-out body cells with new ones, providing new cells needed for growth and development, and healing wounds by making new cells.