Vitamins play an essential role in the proper functioning of metabolic processes within the body. In addition to their necessity for bodily functions, they provide many health benefits and can also improve athletic performance. Vitamins are vital in the growth and recovery of cells and tissue. They are an essential element in the diet, because most vitamins are not formed in the body, but do occur naturally in foods. There are some vitamins that are produced in the body, however, they are only formed in trace amounts, rendering them inadequate for proper bodily functions. If one vitamin is not sufficiently present, metabolic activities can be adversely impaired. Even though vitamins have a nutritional content, they are not metabolized for energy purposes. They do, however, play an essential role in the production of energy. Vitamins can also act as cofactors to the metabolic process.
Vitamins are differentiated by their solubility characteristics. The fat-soluble vitamins are A (retinol), D (calciferol), E (tocopherol) and K (phylloquinone). The water-soluble vitamins are the B-complex vitamins (thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, cobalamin, folate and biotin) and Vitamin C (ascorbic acid). Fat-soluble vitamins are soluble in lipids, which allows them to be stored in the liver, along with fat, in large amounts. Water-soluble vitamins are soluble in water, and therefore are not stored in the body in large amounts because of their tendency to be flushed out. The body can only store water-soluble in small amounts. Because of this, they must be consumed daily. Whole foods are good sources of vitamins because they occur naturally within them.
Another organic substance, metabolites, is often referred to as pseudo-vitamins because they possess vitamin-like properties. These metabolic intermediaries are also essential to good health, but unlike vitamins, the body produces adequate quantities of metabolites and therefore does not require a daily consumption.
Fat Soluble Vitamins
Vitamins A (retinol), D (calciferol), E (tocopherol) and K (phylloquinone) are fat-soluble vitamins. They are soluble in lipids and organic solvents. This property allows them to be stored in large quantities in the liver and fat tissues. Many people, who take these vitamins on a regular basis, are unaware of the potential risks associated with overdosing. Vitamin toxicity is not common; however the capacity of these vitamins to be stored in harmful levels is a possibility. Often, an over-abundance of fat-soluble vitamins is not evidently toxic, but it can lead to impaired performance.
In addition to fat-soluble vitamins potentially becoming a contributor of toxicity, they may also be subject to deficiency. Because these vitamins can only be stored in the presence of fat, they are often deficient in low-fat, low-calorie diets. A diet low in fat could result in malabsorption, and may lead to a low functioning of bodily mechanics. If supplements are to be added as part of the diet, oil based forms should be ingested with a meal.
Compound – Vitamin A (retinol) is an organic compound. This fat-soluble compound is displayed in two groups of chemicals known as retinoids and caretenoids.
Function – Vitamin A is vital for vision. A deficiency of this vitamin can lead to night blindness. It is essential for cellular growth and bone development. It also plays a major role in the reproductive system and the body’s immune system.
Source – Food sources of Vitamin A are cod liver oil, egg yolks, fish, milk, cantaloupe, carrots, broccoli, and leafy green vegetables.
Beta-carotene is a precursor to Vitamin A. Beta-carotene is an antioxidant that assists in destroying free radicals. Excessive intake of Vitamin A may lead to toxicity, whereas high amounts of beta-carotene are not known to be toxic.
Compound – Vitamin D (calciferol) is an organic, fat-soluble compound that exhibits hormonal activity and acts as a signaling mechanism in cell and bone growth. In the presence of UV light, the body manufactures Vitamin D.
Function – The main function of Vitamin D is in growth and development of teeth and bones. Vitamin D is essential for proper absorption of calcium within the body. A deficiency of this vitamin may lead to soft bones and unhealthy teeth.
Source – Food sources of Vitamin D are cod liver oil, eggs, fish, butter, cream and milk.
Compound – Vitamin E (tocopherol) is an organic, fat-soluble compound. Tocopherols make up the majority of compounds exhibiting Vitamin E activity. Vitamin E acts as an antioxidant.
Function– The primary function of Vitamin E is in the formation of red blood cells and it also acts as an antioxidant. As an antioxidant, Vitamin E assists in minimizing cellular damage. It is also involved in the synthesis of DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). Vitamin E plays an important role in the reproductive system. Vitamin E is an essential nutrient for athletic performance and enhancement.
Source – Food sources of this vitamin are wheat germ oil, liver, nuts, leafy green vegetables, and coconuts.
Compound – Vitamin K (phylloquinone) is an organic, fat-soluble vitamin that breaks down in the presence of sunlight. Phylloquinone is the main compound that displays Vitamin K activity.
Function – The primary function of Vitamin K is to aid the body in the formation of prothrombin. This substance is essential for the blood clotting processes within the body. Deficiencies of prothrombin can lead to hemorrhaging.
Source – The main food sources of Vitamin K are in leafy green vegetables, Brussels sprouts, cabbage, avocados, and kiwis.
Water Soluble Vitamins
The B-complex vitamins (thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, cobalamin, folate and biotin) and vitamin C (ascorbic acid) are the water-soluble vitamins. Because these vitamins are soluble in water, they are often flushed out of the body and therefore not stored in the body in large or adequate amounts. In addition, these vitamins are often lost during food preparation (cooking). Because of these factors, water-soluble vitamins require daily consumption in order to prevent a vitamin deficiency. The B-complex vitamins play an important role in the metabolism of fats, proteins and carbohydrates. Due to their involvement in the metabolic processes, any depletion of B vitamins could have adverse results in the activation of the metabolic pathways.
Compound – Vitamin B1 (thiamin) is an organic compound. This water-soluble vitamin is converted into coenzymes. It plays a role in metabolic function within the body.
Function – The primary function of Vitamin B1 is to aid the body in the metabolism of carbohydrates, by converting thiamin into a coenzyme. It also plays a role in appetite stimulation.
Source – The main food sources are rice bran, pork, yeast, oatmeal, asparagus and potatoes.
Compound – Vitamin B2 (riboflavin) is an organic compound. This water-soluble vitamin, like all other B-complex vitamins, has coenzyme activity roles within the body.
Function – The primary function of Vitamin B2 is in the production of energy and cellular respiration. Riboflavin acts as two coenzymes in the metabolism of carbohydrates and fats. Some amino acids are also broken down in the presence of riboflavin.
Source – The main food sources are eggs, fish, poultry, yogurt, milk, nuts, and green vegetables.
Compound – Vitamin B3 (niacin) is an organic compound. This water-soluble vitamin functions as a precursor to the coenzymes NAD (nicotinamide adenine dinucleotide) and NADP (nicotinamide adenine dinucleotide phosphate).
Function – The primary function of Vitamin B-3 is in several metabolic processes, such as the production of energy, protein metabolism, and the synthesis of amino acids and hormones.
Source – The main food sources are liver, meats, whole grains, potatoes, nuts and legumes.
Compound – Vitamin B5 (pantothenic acid) is an organic compound. This water-soluble vitamin of the B-complex group is a component of Coenzyme A (CoA).
Function – Vitamin B5 has a vital role in the synthesis and metabolism of fatty acids, carbohydrates and proteins. As a component of CoA, this compound also plays an essential role in the Kreb’s cycle.
Source – Pantothenic acid is found in most foods, and in large amounts in liver, whole grain cereals, legumes, eggs and meats.
Compound – Vitamin B6 (pyridoxine) is an organic compound. This water-soluble vitamin, of the B-complex family, displays coenzyme activity and is vital in amino acid metabolism.
Function – The primary function of Vitamin B6 is in the breakdown of proteins and in the metabolism of amino acids and fats. It acts as a substrate during gluconeogenesis. Pyridoxine is needed to help balance sodium and potassium, assisting in red blood cell production.
Source – The main food sources are, whole grains, meats, liver, rice, soybeans, vegetables, bananas, and nuts.
Compound – Vitamin B7 (biotin) is an organic compound. This water-soluble compound is a member of the B-complex vitamins and acts as an enzyme during several metabolic processes. Because it is produced in the intestines, deficiencies are not as common.
Function – Biotin acts as an enzyme and is required in the process of synthesizing amino acids and fatty acids. It is essential during gluconeogenesis. Biotin is vital in the formation of new cells and helps to promote healthy nerve tissue and bone marrow. It also promotes healthy hair and skin.
Source – The main food sources are liver, milk, and egg yolk. It can also be obtained through the consumption of nuts, legumes, brewer’s yeast and some vegetables.
Compound – Vitamin B9 (folic acid or folate) is an organic water-soluble compound. It is also known as folate and displays chemical properties as a coenzyme during varying metabolic functions.
Function – Folic acid is required for metabolism and plays a vital role in the synthesis of DNA and RNA. Another main function of folate is in the metabolism of amino acids. It is also necessary in the production of red blood cells, tissue growth and the regeneration of muscle tissue.
Source –Folate is abundant in dark green and leafy vegetables. Some folate containing vegetables are asparagus, spinach, collards, kale and broccoli. Folate is also found in red meat, salmon and liver.
Compound – Vitamin B12 (cyanocobalamin) is an organic compound. In the presence of air, this water-soluble vitamin is the most stable of any B-complex vitamin.
Function – Vitamin B12 is required for proper brain and nervous system function. It is necessary for multiple metabolic functions, including cell growth and development, nerve development, synthesis of DNA and energy production. This vitamin is considered the “energy vitamin”.
Source – The main food sources are liver, shellfish, milk, eggs, lamb, pork liver and poultry.
Compound – Vitamin C (ascorbic acid) is an organic water-soluble compound. It is an antioxidant that cannot be synthesized within the body.
Function – Vitamin C functions as an enzyme and cofactor involved in protein formation. It is also very important in maintaining healthy tissues and cells. This compound plays a major role in helping fight infection and promoting overall health. It assists in preventing the degeneration of cells and tissues.
Source – The main food sources are citrus fruits, strawberries, tomatoes, broccoli, spinach, peppers and potatoes.