Types of Vitamins and their Functions

Vitamins are essential nutrients that play an important role in maintaining your overall health. There are 13 types of vitamins which are mainly classified based on their solubility and a human body requires all of them to function properly.

Types of Vitamins

In terms of the classification of vitamins, they are classified into two primary categories based in their solubility in water or fat:

1. Fat-soluble Vitamins

These vitamins are absorbed along with fats and are stored in the body’s fatty tissues and liver. As they can be stored, excessive intake of fat-soluble vitamins can lead to toxicity. The fat-soluble vitamins include:

• Vitamin A

• Vitamin D

• Vitamin E

• Vitamin K

2. Water-soluble vitamins

These vitamins dissolve in water and are not stored in the body to a significant extent. They need to be consumed regularly because excess amounts are excreted in urine. The water-soluble vitamins include:

• Vitamin C (Ascorbic acid)

• B1 (Thiamine)

• B2 (Riboflavin)

• B3 (Niacin)

• B5 (Pantothenic acid)

• B6 (Pyridoxine)

• B7 (Biotin)

• B9 (Folate, Folic acid)

• B12 (Cobalamin)

Role of Vitamins

Each vitamin plays specific roles in the body, contributing to various physiological functions. Here’s an overview of the roles of different types of vitamins:

1. Vitamin A (Retinol)

Essential for vision, skin health, and immune function. Its deficiency may lead to vision loss, blindness, growth issues, and other health complications.

2. Vitamin D ( Calciferol)

Promotes calcium absorption, critical for bone health, and plays a role in immune function. Long-term vitamin D deficiency may lead to infections, neurological diseases, cardiovascular problems, etc.

3. Vitamin E (Tocopherol)

Acts as an antioxidant protecting cells from damage, and supports skin health. Low levels of vitamin E can lead to vision deterioration, muscle weakness, problems with the immune system, etc.

4. Vitamin K (Phylloquinone)

Necessary for blood clotting and bone metabolism. Vitamin K deficiency may lead to bleeding diathesis.

5. Vitamin C (Ascorbic acid)

Supports the immune system, aids in collagen formation, helps with wound healing, and acts as an antioxidant. Some signs of vitamin C deficiency include anaemia, reduced wound healing rate, scaly skin, easy bruising, etc.

6. B-Complex Vitamins (B1, B2, B3, B5, B6, B7, B9, B12)

These vitamins collectively contribute to energy metabolism, nerve function, RBC formation, and the maintenance of healthy skin, hair, and eyes. Deficiency of these vitamins may lead to sore throat, anaemia, inflammation of lips, fatigue, vomiting, etc.

7. Vitamin B7 (Biotin)

Supports metabolism and helps maintain healthy hair, skin, and nails. Symptoms of biotin deficiency are alopecia, lethargy, seizures, etc.

8. Vitamin B9 (Folate, Folic acid)

Important for DNA synthesis, cell division, and preventing neural tube defects during pregnancy. Low levels of folate can cause poor growth, glossitis, diarrhoea, etc.

9. Vitamin B12 (Cobalamin)

Necessary for RBC formation, nerve function, and DNA synthesis. Vitamin B12 deficiency may lead to certain types of anaemia and neurological problems.

Also Read: How to Avoid Vitamin B12 Deficiency?

Recommended daily intake of vitamins

As per FDA, the recommended daily intake value of vitamins for adults is as follows: