Vitamin Chart

A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. A compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on the circumstances and the particular organism. For example, ascorbic acid functions as vitamin C for some animals but not others, and vitamins D and K are required in the human diet only in certain circumstances.

Vitamins are classified by their biological and chemical activity, not their structure. Thus, each "vitamin" may refer to several vitamer compounds that all show the biological activity associated with a particular vitamin. Such a set of chemicals are grouped under an alphabetized vitamin "generic descriptor" title, such as "vitamin A," which includes the compounds retinal, retinol, and many carotenoids. Vitamers are often inter-converted in the body. The term vitamin does not include other essential nutrients such as dietary minerals, essential fatty acids, or essential amino acids, nor does it encompass the large number of other nutrients that promote health but are otherwise required less often.

Vitamins have diverse biochemical functions, including function as hormones (e.g. vitamin D), antioxidants (e.g. vitamin E), and mediators of cell signaling and regulators of cell and tissue growth and differentiation (e.g. vitamin A). The largest number of vitamins (e.g. B complex vitamins) function as precursors for enzyme cofactor bio-molecules (coenzymes), that help act as catalysts and substrates in metabolism. When acting as part of a catalyst, vitamins are bound to enzymes and are called prosthetic groups. For example, biotin is part of enzymes involved in making fatty acids. Vitamins also act as coenzymes to carry chemical groups between enzymes. For example, folic acid carries various forms of carbon group – methyl, formyl and methylene - in the cell. Although these roles in assisting enzyme reactions are vitamins' best-known function, the other vitamin functions are equally important.

Until the 1900s, vitamins were obtained solely through food intake, and changes in diet (which, for example, could occur during a particular growing season) can alter the types and amounts of vitamins ingested. Vitamins have been produced as commodity chemicals and made widely available as inexpensive pills for several decades, allowing supplementation of the dietary intake.

The discovery of vitamins and their sources
Vitamin	Source
Vitamin A (Retinol)	Cod liver oil
Vitamin B1 (Thiamin)	Rice bran
Vitamin C (Ascorbic acid)	Lemons
Vitamin D (Calciferol)	Cod liver oil
Vitamin B2 (Riboflavin)	Eggs
Vitamin E (Tocopherol)	Wheat germ oil, Cosmetic and Liver
Vitamin B12 (Cyanocobalamin)	Liver
Vitamin K (Phylloquinone)	Alfalfa
Vitamin B5 (Pantothenic acid)	Liver
Vitamin B7 (Biotin)	Liver
Vitamin B6 (Pyridoxine)	Rice bran
Vitamin B3 (Niacin)	Liver
Vitamin B9 (Folic acid)	Liver

Nutrition

Between the extremes of optimal health and death from starvation or malnutrition, there is an array of disease states that can be caused or alleviated by changes in diet. Deficiencies, excesses and imbalances in diet can produce negative impacts on health, which may lead to diseases such as scurvy, obesity or osteoporosis, as well as psychological and behavioral problems. The science of nutrition attempts to understand how and why specific dietary aspects influence health.

Nutrients in food are grouped into several categories. Macronutrients means fat, protein, and carbohydrates. Micronutrients are the minerals and vitamins. Additionally food contains water and dietary fiber.

Food

Food is any substance, usually composed primarily of carbohydrates, fats, water and/or proteins, that can be eaten or drunk by an animal or human for nutrition or pleasure. Items considered food may be sourced from plants, animals or other categories such as fungus or fermented products like alcohol. Although many human cultures sought food items through hunting and gathering, today most cultures use farming, ranching, and fishing, with hunting, foraging and other methods of a local nature included but playing a minor role.

Most traditions have a recognizable cuisine, a specific set of cooking traditions, preferences, and practices, the study of which is known as gastronomy. Many cultures have diversified their foods by means of preparation, cooking methods and manufacturing. This also includes a complex food trade which helps the cultures to economically survive by-way-of food, not just by consumption.

Many cultures study the dietary analysis of food habits. While humans are omnivores, religion and social constructs such as morality often affect which foods they will consume. Food safety is also a concern with foodborne illness claiming many lives each year. In many languages, food is often used metaphorically or figuratively, as in "food for thought".