13 Essential Vitamins and Their Important In Human Body

13 Essential Vitamins and There Important In Human Body

Vitamins are a group of substances that are needed by the body for proper function, growth, and development.

There are 13 essential vitamins required for the body to work properly and they are:

  1. Vitamin A
  2. Vitamin B1 (thiamine)
  3. Vitamin B2 (riboflavin)
  4. Vitamin B3 (niacin)
  5. Pantothenic acid (B5)
  6. Vitamin B6
  7. Biotin (B7)
  8. Folate (folic acid and B9)
  9. Vitamin B12 (cyanocobalamin)
  10. Vitamin C
  11. Vitamin D
  12. Vitamin E
  13. Vitamin K

Categories of Vitamins

These are grouped into two categories namely Fat-Soluble Vitamins and Water-Soluble Vitamins.

Fat-Soluble Vitamins are vitamins A, D, E, and K, usually stored in the body’s fatty tissue. The presence of dietary fat aids the easy absorption of these vitamins by the body.

Water-Soluble Vitamins, there are 9 known water-soluble vitamins. They include Vitamin B1 (thiamine), vitamin B2 (riboflavin), vitamin B3 (niacin), Pantothenic acid (B5), Biotin (B7), Vitamin B6, Vitamin B12 (cyanocobalamin), Folate (folic acid and B9), and vitamin C.

With the exception of Vitamin B12 which is the only water-soluble vitamin that can be stored in the liver for many years. Other water-soluble vitamins don’t get stored in the body. Leftovers leave the body through the urine. To keep up with the body’s demand, there is a need for adequate consumption to prevent shortages in the body.

In this article, our attention is going to be focused on Fat-Soluble Vitamins. You will get to know about their functions, types and constitutes, diatery sources, and the deficiency threats they pose when not consumed in our daily diets. Of course, we shall likewise discuss the Water-Soluble Vitamins in the same manner in Part two of this article so to keep you informed about all the essential vitamins needed for healthy living.

In Focus: Fat-Soluble Vitamins

The Fat-Soluble Vitamins are A, D, E, K. Now let’s get down to its characteristics such as function, constituent, types, sources, deficiency, and overdose.

Read Also:  9 Things You Can Do Every Day to Improve Your Mental Health

1). Vitamin A

Vitamin A is a nutrient that the body needs in small amounts to function and stay healthy.

The Characteristics of Vitamin A include:

1. Function

The major functions of Vitamin A in the body include contributions to healthy vision, bone growth, growth of epithelium and immunity.

2. Deficiency

  • A long-term deficiency can cause loss of night vision and decline further leading to a total loss of vision.
  • Risk factors for vitamin A deficiency can affect a person who follows a plant-based diet and cystic fibrosis.

3. Constituent/ Types

  • Collection of compounds known as retinoids sums up to constitute vitamin A. Retinoids are found naturally in the human body. They are also found present in some dietary sources.
  • Embedded in some foods are retinols, of which the body can use directly as vitamin A. Others stores provitamin A compounds, which the body converts into vitamin A.

Types of Vitamin A include:

  • Retinol
  • Beta-carotene

4. Dietary Sources

1. Animal sources provide ready-to vitamin A, or retinols.

They include:

  • Fish liver oil
  • Beef liver
  • Cheese, milk, and other dairy products

2. Plant sources provide carotenoids that get converted by the body into vitamin A.

These sources include:

  • Sweet potato
  • Kale, spinach, and other green, leafy vegetables
  • Carrots
  • Cantaloupe
  • Black-eyed peas
  • Fortified breakfast cereals

 5. Overdose

1. Vitamin A overdose can be toxic.

Risk factors for overdose include:

  • High consumption of vitamin A supplements
  • high intake of fish liver oil
  • Intake of medications that contain retinoids, such as acitretin (Soriatane), a treatment for psoriasis.

2. High levels of vitamin A can be dangerous to a growing foetus during pregnancy.

Symptoms of an overdose include:

  • Headaches
  • Fatigue
  • Nausea
  • Dizziness
  • Coma and death in severe cases.

2). Vitamin D

Vitamin D can be obtained naturally from sunlight or in the diet.

1. Function

  • It functions to maintain healthy bones.
  • It fortifies the immune system.

2. Constituent/ Types

  • Vitamin D are a group of compounds together known as calciferol.
  • Calciferol is absorbed into the bloodstream by the body. It is then converted into calcitriol.
Read Also:  Paedophile Disorder: a sexual attraction towards children

Types of Vitamin D include:

  • Vitamin D-3 can be found in animal fats.
  • Vitamin D-2 can be found in plants, e.g. mushrooms.

3. Dietary Sources

Dietary sources include:

  • Oily fish and fish oils.
  • Fortified dairy products, plant-based milks, and cereals.
  • Beef liver.
  • Eggs

4. Deficiency

1. Vitamin D deficiency causes the following:

  • Loss of bone mass( osteoporosis)
  • Osteomalacia
  • Rickets, increased risk of infection and autoimmunity

2. Vitamin D deficiency risk factors:

  • Spending less time outdoors
  • Darker skinned people
  • Underlying chronic health conditions
  • Obesity

5. Overdose

  • An overdose of vitamin D is very much unlikely. Although, it is likely that using supplements excessively could trigger this.
  • Excess vitamin D could cause high levels of calcium in the blood.

This can lead to:

  • Nausea
  • Headaches
  • Low appetite and weight loss
  • Heart or kidney damage
  • High blood pressure

3). Vitamin E

Vitamin E is an antioxidant that can help the body destroy free radicals that causes damage to the cells. They help to prevent cancer in this regard.

1. Function

Functions of vitamin E in the body are:

  • They act as an antioxidant
  • They help to boost the immune system
  • They help to dilate blood vessels and help prevent clotting

Types of Vitamin E:

  • Only eight forms of Vitamin E exist, but only alpha-tocopherol meets humans’ needs.
  • Alpha-tocopherol
  • Beta-tocopherol
  • Gamma-tocopherol
  • Delta-tocopherol
  • Alpha-tocotrienol
  • Beta-tocotrienol
  • Gamma-tocotrienol
  • Delta-tocotrienol

2. Dietary Sources

Sources include:

  • Wheat germ oil
  • Sunflower seeds and oil
  • Almonds, hazelnuts, and peanuts
  • Spinach and broccoli
  • Kiwi fruit and mango

3. Deficiency

1. Vitamin E deficiency can cause:

  • Damages to the nerves and muscles of the body leading to movement and coordination problems.
  • Vision problems.
  • A weakened immune system.
  • Increased overall risk of various diseases, being an antioxidant.

2. Vitamin E Deficiency Risk factors

  • People with Crohn’s disease or cystic fibrosis are more susceptible. The liver’s ability to absorb vitamin E is affected by these conditions.
Read Also:  Computer programme identifies breast cancer during routine scans

4. Overdose

Although excessive supplement use can increase the risk of an overdose, vitamin E intake from natural sources is unlikely to lead to an overdose. One major precaution with the consumption of vitamin E is that it may interfere with blood clotting for people who use blood-thinning medication, such as warfarin (Coumadin).

4). Vitamin K

Vitamin K helps to prevent excessive bleeding. That is, they help to form blood clot.

The two most common groups of vitamin-k are:

  • Vitamin K-1 (phylloquinone). It can be derived from green, leafy vegetables and some other plant sources.
  • Vitamin K-2 (menaquinones). This can be found in animal sources and fermented foods

Several other forms exist. From synthetic forms to other forms that the body produces.

1. Function

Apart from helping the body to form blood clots, Vitamin K may also:

  • Reduce the risk of heart disease.
  • Improve bone health.
  • Help to reduce the build-up of calcium in the blood.

2. Dietary Sources

Both types of vitamin K can be gotten from Kale, Liver, Spinach, Parsley, Butter, and Egg yolks

3. Deficiency

These include:

  • Lack of vitamin k can cause
  • Excess bleeding
  • Lower bone density

3 Overdose

Intake of Vitamin K in high quantity does not appear to have adverse effects. But, it can react with blood-thinning medications such as warfarin.


All fat-soluble vitamins highlighted in this article are needed for the overall health of the body. It is possible to obtain enough of each vitamin from a well-planned varied and healthful diet. It is best for anyone who has concerns about their vitamin intake to speak to a doctor.

Depending on some cases, a doctor recommending the use of supplements is not farfetched. Supplements should be taken on doctor’s prescriptions to avoid toxicity.