In a paper, prepared for the Council of Responsible Nutrition (CRN) in 2002, Annette Dickinson answers the question — what are vitamins? "Vitamins are substances that, by definition, are essential to life itself, but are not made in the body- or not made in sufficient quantities to support life."
The body only requires small amounts of each vitamin; they are micronutrients. However, daily vitamins from food is necessary for life, and often nutritional vitamin supplements are required.
Vitamins are organic substances containing carbon, hydrogen and oxygen, which fall into two categories— fat soluble vitamins and water soluble vitamins. Each group has unique and important characteristics.
Nutrition facts: Before a substance is classified a vitamin it must show that when it is removed from the diet it will cause a deficiency disease or disorder, and when it is reintroduced into the diet, it must cure or prevent that condition.
What are Fat Soluble Vitamins and Water Soluble Vitamins?
The differences between fat soluble vitamins and water soluble vitamins affect their absorption, metabolism, excretion and function.
Water soluble vitamins love water. They show the following characteristics:
- Are absorbed directly into the bloodstream
- Travel freely throughout the body
- Are not stored in any appreciable amounts
- If taken in excess of what your body needs they are excreted through the urine
- Have few toxicity concerns due to excess being excreted easily
- Are required in frequent doses because they are not stored within the body.
Fat soluble vitamins love fat. They show the following characteristics:
- Are absorbed into the lymphatic system before the blood stream
- May require proteins to transport them throughout the watery parts of the body
- Are readily stored in fatty tissue
- If taken in excess they can be stored in fatty tissue or excreted through the faeces or urine.
- Can be toxicity issues if taken in large amounts for a certain time
- Are needed in less frequent doses, as they are not readily excreted.
The fat soluble vitamins are vitamins A, D, E and K. The main water soluble vitamins are the vitamin B group and vitamin C.
Nutrition facts: Absorption of fat soluble vitamins is improved if the nutrient is eaten or taken in a fatty or oily substance. A large salad of broccoli, carrots, red peppers, spinach, parsley, almonds, sunflower seeds, avocado, and salmon drizzled with extra virgin olive oil will provide you with a good dose of fat soluble vitamins.
The Main Benefits of Vitamins Within the Body
The main role of the vitamin B group is to assist enzymes; they are classed as co-enzymes.
The vitamin B group includes the following:
- thiamin (vitamin B1)
- riboflavin (vitamin B2)
- niacin (vitamin B3)
- pantothenic acid (vitamin B5)
- vitamin B6
- folate/folic acid
- vitamin B12
- biotin.
These vitamins are beneficial by influencing energy metabolism, blood cell production and development, as well as many other metabolic functions. Rarely will the B vitamins function alone, they will often need one or more to do their job.
Vitamin C is an antioxidant but is also vital for the production of collagen and enhances iron absorption.
The functions of the fat soluble group are more individual.
Vitamin A is required for vision, cell development, growth and division, immune function, red blood cell production, and as beta-carotene—an antioxidant.
Vitamin D maintains the level of calcium and phosphorus in our body; therefore, it is for bone health. It is also required for cell differentiation, and immunity.
Vitamin E is a powerful antioxidant, quenching free radicals and preventing cell damage or death. It also assists in cell signalling or communication, immunity, and inflammation reduction.
Vitamin K produces proteins required for blood coagulation (clotting), bone mineralisation, and cell proliferation.
If the required amount of both fat soluble and water soluble vitamins is not consumed or there is an underlying condition that reduces the amount available to the body, then nutritional vitamin supplements are required. Because B vitamins often work together, if taking a high dose, single vitamin B, it seems logical that a daily multi-vitamin supplement or complete vitamin B supplement should also be taken.
The nutrition facts show the benefits of vitamins are numerous and vital for human health.
Daily vitamins are essential to life.
For more information on vitamins read what are vitamins and why are they important?
For information on minerals read "Health Facts: Natural Minerals"
Resources:
Bender DA. Nutritional Biochemistry of the Vitamins. 2nd ed. Cambridge: Cambridge University Press; 2003.
Bland J, S., Costarella L, Levin B, Liska D, Lukaczer D, Schiltz B, et al. Clinical Nutrition: A Functional Approach. 2nd ed. Washington, USA: Institute for Functional Medicine; 2004.
Melissa Peterson - Melissa Peterson is a naturopath specializing in nutrition education. Melissa has been writing and editing technical and patient-friendly ...
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