Vitamins

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Vitamins are one of the two groups of substances that are classified as micronutrients, that are essential to human nutrition.

Vitamins are organic, meaning they contain carbon and are found in plant and animal substances in small amounts. We obtain vitamins by eating the plants and animals that make them

Most vitamins cannot be made in our bodies; exceptions are some of the b vitamins, which can be made from our intestinal bacteria and occasional biochemical conversions from a precursor of the required vitamin, like beta-carotene is converted to vitamin A.

Vitamins are not a source of energy.

Vitamins help convert macronutrients to more bio-available, or metabolically useful forms.

Vitamins function as coenzymes (in collaboration with enzymes) for a variety of metabolic reactions and biochemical mechanisms within out many bodily systems. Each enzyme is specific to one biochemical reaction. Enzymes speed up specific chemical reactions that would proceed very slowly, if at all, without vitamins.

Vitamins are not part of our body tissues, they are not building blocks but helpers in metabolism.

We need food and certain minerals to best absorb any vitamin supplements we take.

Vitamins are essential for growth, vitality, and health, and are helpful in digestion, elimination, and resistance to disease. Depletions or deficiencies can lead to a variety of both specific nutritional disorders, and general health problems, according to what vitamin is lacking in the diet.

Vitamins are usually classified in to categories: water soluble and fat soluble.

Water soluble vitamins include mainly the b vitamins, and vitamin C. The are most likely to be lost when foods are cooked, because they are sensitive to heat. Water soluble vitamins can also be lost from raw foods because they can be sensitive to air, light and the passage of time. The more passing of time between harvest and eating, the more water soluble vitamins are lost. Water soluble vitamins are commonly found in vegetable sources and less common in animal sources.

Water soluble vitamins are not stored in the body to a very large degree, so they are needed regularly in our diets. This makes them much less potentially toxic than fat soluble vitamins which are stored when taken in higher doses. Most water soluble vitamins act in the body as coenzymes in combination with an inactive protein to then make it an active enzyme.

Fat soluble vitamins are Vitamins A, D, E, and K, which are found in the lipid components of both vegetable and animal source foods.

Grains, nuts and seeds contain vitamin E, and many vegetables contain vitamin A, or more commonly Vitamin A's precursor beta-carotene.

Fat soluble vitamins can be stored in the body tissues, so we can function for longer periods of time without obtaining them through diet, unlike water soluble vitamins. Toxic levels can occur more easily from regular increased intake of these vitamins, especially vitamin A; Vitamin D and K can also cause problems when taken in high doses. toxicity from vitamin E is less likely because it is used readily by the body as an antioxidant help protect against harmful byproducts of metabolism, and against outside pollutants.

Vitamin A adds cellular protection as well as resistance to infection.

Vitamin D aids in absorption of calcium from the gut and thus is important to skeletal health.

Vitamin K helps make factors crucial to blood clotting to prevent bleeding.

Dietary Reference Intakes:

Adequate intake (AI)- recommended average daily nutrient intake level based on observed or experimentally determined estimates of nutrient intake by a group of apparently healthy people

Estimated Average Requirement (EAR)- Data based, statistically relevant estimate of the average daily nutrient intake level that will meet the requirement of half of the healthy individuals in a given life stage and gender group

Recommended Dietary Allowances (RDA)- Average daily nutrient intake level sufficient to meet the nutrient requirement of nearly all healthy individuals in a particular life stage and gender group. (97-98%)

Tolerable Upper Intake Level (UL)- Highest average daily nutrient intake level likely to pose no risk of adverse health effects to almost all individuals in the general population

Other Nutritional Supplement Terms

Natural- vitamins are considered natural when they are extracted exclusively from food sources and contain the specific mix of nutrients found in nature. Often the mix includes other enzymes, catalysts, or minerals to aid the body's use of the vitamins. Amounts of individual nutrients in purely natural vitamins are usually not very high, and this many higher dose vitamins contain a combination of natural and synthetic vitamins. In terms of nutritional labeling, there is no legal definition of natural, and products bearing this label may or may not meet the criteria as described.

Synthetic- When vitamins are made chemically in the laboratory, rather than extracted from foods. Amounts of these vitamins can range from low to very high. Synthetic vitamins are able to perform the same function and chemical reactions in the body as natural vitamins (because they have the same chemical structure) however, many people, especially those sensitive to chemicals, do not tolerate them well. Synthetic vitamin products are more likely to contain binders and fillers that may cause allergic reaction or gastrointestinal distress those from natural sources

Organic- All vitamins are organic in that they contain carbon, however here it means that foods or supplements come from pesticide and herbicide free plant sources or naturally raised animals. When vitamins are naturally derived from organically grown food, they can truly be called organic vitamins.

Inorganic- Agriculturally speaking, almost all nutritional supplements are inorganic, in the sense that they are chemically manufactured or extracted from foods grown with chemicals.

Chelated- When minerals are bound to another molecule to enhance absorption from the digestive tract. the organic molecule must have a special chemical arrangement and a special charge to hold the mineral.

Time Release- Vitamins that may be manufactured in micro pellets within the vitamin pill. Micro pellets are digested and absorbed into the body slowly, "time release" usually over an 8-12 hour period

Orthomolecular medicine- Treating each individuals medical problems with the appropriate level, or right amount of each nutrient, usually higher levels of the various vitamins and minerals than the RDAs. Orthomolecular medicine is to achieve a balanced metabolism by having the appropriate nutrient or biochemical molecule in the appropriate location at the appropriate time.

Orthomolecular psychiatry- Type of orthomolecular medicine where the large doses of vitamins and minerals are used in conjunction with therapy for psychiatric conditions such as depression and schizophrenia

Megavitamin Therapy- simplistic extension of the orthomolecular approach, using dosages many times the RDAs to prevent problems, treat certain biological symptoms and potential genetic and nutritional deficiencies, and obtain optimum health.

Vitamin Availability

Available in tablets, capsules, powdered vitamins, liquid vitamins

Tablets- Most common because of their convienience