Vitamins are organic substances that the body requires in small amounts for metabolism but is unable to make for itself, at least in sufficient quantities. Vitamins generally are unrelated chemically and differ in their physiological actions.
Understanding Key Vitamins and Minerals
The role of many vitamins is to help make possible the processes by which other nutrients are digested, absorbed and metabolised or built into body structures.
The Fat Soluble Vitamins
Vitamin A is one of the most versatile vitamins with roles in such diverse functions as vision, maintenance of body linings and skin, bone growth and reproduction.
Vitamin D and it’s derivatives are all sterols. Certain sterols when exposed to ultraviolet light undergo small structural changes that are of importance in nutrition, they are called vitamin D2 and D3.
Vitamin E (the tocopherols). There are four different types, alpha, beta, gamma and delta tocopherol.
Vitamin K exists in nature in two forms – K1 and K2, but only vitamin K1 is of importance nutritionally. Natural Vitamin K1 is yellow oil, soluble in fat solvents, but only slightly in water.
The Water Soluble Vitamins
The B-Group Vitamins
The B vitamins have much in common, they act as part of coenzymes, in that they combine with an inactive protein to form an active enzyme.
Thiamine – Vitamin B1
Thiamine is a white crystalline substance, readily soluble in water but not in fat or fat solvents. It is rapidly destroyed by heat in neutral or alkaline solutions.
Riboflavin – Vitamin B2
Riboflavin is a yellow crystalline substance, slightly soluble in water but not in fats. Though stable to boiling in an acid solution, in an alkaline solution it is readily decomposed by heat.
Pantothenic Acid – Vitamin B3
Pantothenic acid is a constituent of coenzyme A and is present in all living matter. It’s distribution in natural foods is so wide-spread that deficiency of the vitamin is unlikely to occur in man except perhaps when processed foods form large proportions of the diet.
Biotin – Vitamin B4
Biotin is one of the most active biological substances known in living matter. It is mostly bound to protein, probably as the coenzyme of several enzymes.
Nicotinic Acid (Niacin) – Vitamin B5
Niacin is a white crystalline substance readily soluble in water and resistant to heat oxidation and alkalis.
Pyridoxine and Related Compounds – Vitamin B6
Vitamin B6 consists of three closely related chemical compounds – pyridoxine, pyridoxal and pyridoxamine with similar physiological actions.
Cyanocobalamin – Vitamin B12
Cyanocobalamin is named for its content of the mineral cobalt which gives the crystalline form its red colour.
Ascorbic Acid – Vitamin C
Ascorbic acid is a simple sugar. It is a white crystalline substance, stable, when dry, in air and light. It is very soluble in water and easily oxidised in alkaline solution and on exposure to heat, light and traces of metals especially copper.