The Vitamins Guide

Vitamins are natural and essential nutrients, required in small quantities, playing a major role in growth and development, repair and healing wounds, maintaining healthy bones and tissues for the proper functioning of the immune system, and other biological functions. Thus, the absence or deficiency of vitamins causes deficiency disorders.

They are classified into two types based on their solubility.

Fat-soluble vitamins

Water-soluble vitamins

Fat-soluble Vitamins

The fat-soluble vitamins, such as A, D, E, and K, are stored in the body for longer periods and generally pose a greater risk of toxicity than water-soluble vitamins.

Vitamin A:

Vitamin A exists only in animal-origin feed and occurs in three forms such as;

Retinol
Retinal
Retinoic acid

In plants, exist in provitamin i.e, carotenoids. Beta-carotene is the most active carotenoid. The sources of vitamin A can be animal and plant sources.

Animal sources

Fish liver oil
Egg Yolk
Milk fat

Plant sources

All green leaves are rich in provitamins A, beta carotene.

Diseases due to a Deficiency of Vitamin A

Eye problems, such as vision loss and blindness
Skin issues such as dry, scaly and itchy skin
Growth issues, like delayed growth and development in children
Immune system problems can lead to infection, such as chest and throat infections

Vitamin D:

Vitamin D exists in different forms, including vitamin D2 (ergocalciferol), which is produced from plant sources, and vitamin D3 (cholecalciferol), which is produced by the body from sunlight exposure. Vitamin D3 is the natural form of vitamin D.

Sources

Cod liver oil
Egg yolk
Sun-dried grains

Diseases due to a Deficiency of Vitamin D

Rickets in children
Osteomalacia in adults
Osteoporosis
Retard growth
Increased loss of Ca and P in urine

Vitamin E:

Vitamin E naturally exists in eight forms: alpha, beta, gamma, and delta-tocopherol, and alpha, beta, gamma, and delta-tocotrienol. However, alpha-tocopherol is the more active form. It helps in the absorption and utilization of vitamin A and extends the storage of vitamin A in the liver by protecting it from oxidation. It plays an important role in the development and function of the immune system and is also important for reproduction.

Sources

Cereal grains
Vegetable oils
Fats and nuts
seeds and legumes

Diseases due to a Deficiency of Vitamin E

Infertility in females
Reduces sperm motility in males
Vision problems
Hemolytic anemia

Vitamin K:

Vitamin K exists in two main forms: phylloquinone (K1) and menaquinone (K2). Required for the synthesis of prothrombin and other clotting factors. It also acts as an anti-haemorrhagic vitamin. It is also involved in the electron transport chain and oxidative phosphorylation. This vitamin is mainly synthesized by GI tract microorganisms.

Sources

Green leafy vegetables
Egg yolk
Liver
Fish

Diseases due to a Deficiency of Vitamin K

Cystic fibrosis
Digestive disorders lead to fat malabsorption
Blocked bile duct

Water-soluble vitamins

Vitamins B complex and C are called water-soluble vitamins. They can be easily absorbed but not stored in the body except for vitamin B12. Readily excreted in urine and required in very small amounts, mg or µg. They are unstable to heat and light.

Vitamin B:

Vitamin B consists of eight water-soluble vitamins, each with its unique functions, and is crucial for various body functions, including energy production, nerve function, and red blood cell formation. These include thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folate (B9), and cobalamin (B12).

Sources

Animal products
Leafy green vegetables
Whole grains and legumes
Fortified foods.

Diseases due to a Deficiency of Vitamin B

A severe deficiency of vitamin B1 (thiamin) can cause Beriberi
A deficiency of vitamin B3 (niacin) leads to Pellagra
Vitamin B12 and folate deficiencies can cause megaloblastic anemia

Vitamin C:

Vitamin C mainly exists in two forms, ascorbic acid (the reduced form) and dehydroascorbic acid (the oxidized form). In human blood, it is always found in the reduced form, as ascorbic acid. It helps in the formation of connective tissues, collagen. Helps in the absorption of iron and promotes the healing of wounds and healthy blood vessels. It acts as an antioxidant.

Sources

Citrus fruits like oranges and lemons

Diseases due to a Deficiency of Vitamin C

A severe vitamin C deficiency leads to scurvy, characterized by signs and symptoms such as bleeding gums and easy bruising.
Anemia

Conclusion

Overall, vitamins are classified into two types, including fat-soluble and water-soluble vitamins, which play an important role in maintaining overall health and well-being. Adequate vitamin intake through a balanced diet can help prevent various diseases, which mainly occur due to a deficiency of vitamins.