What are fat soluble vitamins
What Are Fat Soluble Vitamins

What Are Fat Soluble Vitamins: 4 Types, Sources, Functions, Deficiency, and Side Effects

What Are Fat Soluble Vitamins?

Fat-soluble vitamins are vitamins A, D, E and K. For some things, these vitamins differ from water-soluble vitamins. This vitamin is found in fats and oily parts of food. This vitamin is only digested by bile because it is insoluble in water. The following sections provide a detailed overview of each vitamin of this type.

Vitamin A


It is difficult to determine the amount of vitamin A needs. This vitamin is produced from two different compounds that are converted in the body into vitamin A. In animal food sources, it is available in the form of retinol; in plant food sources are in the form of beta-carotene, which is less efficient than retinol for the production of vitamin A. This is what makes the recommended amount of vitamin A given in the form of equivalent retinol, RE. The recommended amount of vitamin A is 1000 micro-grams of RE per day for men and 800 micro-grams for women.

Key sources

Vegetables and fruits are the biggest carriers of vitamin A. Most foods containing vitamin A are brightly colored (although not all brightly colored foods contain vitamin A). Vegetables rich in vitamin A are carrots, yams, pumpkin, spinach and melon. Milk, butter cheese and eggs also contain vitamin A.


Vitamin A is important for the maintenance of corneal and epithelial cells from vision. Vitamin A also aids the growth and reproduction of bones and teeth. In addition, vitamin A also plays a role in the formation and regulation of hormones and helps protect the body against cancer.

Symptoms of deficiency

Vitamin A deficiency can have serious consequences. It is usually accompanied by a lack of protein and zinc minerals. Vitamin A can be stored in the body for a year. This means that the symptoms of deficiency are not noticeable immediately after the cessation of consumption of this vitamin. In any case, if this is apparent after a long time from when there is no consumption, the symptoms may be very obvious and severe.

One of the first symptoms is night blindness. If the deficiency persists, it may also play a role in decreasing corneal function and causing blindness. Deficiency of this vitamin can also prevent bone growth, or cause bone deformation, forming gaps and damage to teeth and stalling the growth of tooth-forming cells. Anemia is another consequence. In addition, this deficiency affects the bone and nervous system, and can result in paralysis.


Vitamin A poisoning occurs when the protein that binds to it has been fulfilled so the free vitamin A can attack the body’s cells. This is usually not the case if the vitamin comes from daily food, but this can happen if a person uses the supplement. Symptoms include nausea, vomiting, abdominal pain, diarrhea and weight loss. The nervous system and muscles can also be affected, causing symptoms such as loss of appetite, irritability, fatigue, insomnia, restlessness, headache and muscle weakness.

Vitamin D

People get vitamin D:

  • Naturally through exposure to sunlight or food
  • Through foods enriched as supplements

Two types of vitamins occur naturally:

  • Vitamin D-3, found in animal fats
  • Vitamin D-2, found in plants, such as mushrooms

Vitamin D has two main roles in the body:

  • Maintain bone health.
  • Supports the immune system.

Food sources

A person can get some vitamin D from the sun, but most people also need to use other sources as well. The main alternative is food.

Food sources of vitamin D include:

  • Fish oil and fish oil
  • Enriched dairy products, vegetable milk, and cereals
  • The cow liver
  • Eggs

The main effects of vitamin D deficiency include osteoporosis, or loss of osteomalacia bone mass, when the bone becomes soft rickets, when the child’s bones do not develop as they should, and increased risk of infection as well as autoimmunity

Too much vitamin D can lead to high levels of calcium in the blood.

It can also cause:

  • Nausea
  • Headaches
  • Low appetite and weight loss
  • Calcium buildup in tissues and blood vessels
  • Damage to the heart or kidneys
  • High blood pressure.

Vitamin E

Vitamin E is included in vitamins that act as antioxidants that help protect cells in the body from damage from free radicals.

Vitamin E is like vitamin A that can be obtained from animal sources and vegetable sources. Sources of vitamin E come from animals such as salmon, goose meat, fish eggs, and fish liver oil. Plant-based sources of vitamin E such as sunflower seeds, hazelnuts, almonds, peanuts, avocados, and kiwis.

Vitamin E Function:

  • Maintain healthy skin and eyes
  • Strengthens the immune system
  • Helps the formation of red blood cells
  • Reduce the risk of cataract disease
  • Slows down aging
  • Treating brain diseases, such as Alzheimer’s, Dementia, and others.

Vitamin K

Also known as phylloquinone or naphthaquinone, vitamin K acts as one of the factors in the process of blood clotting after the occurrence of wounds. Vitamin K was discovered by a Danish researcher, and the Danish word clotting begins with the letter “K”, this explains why it is referred to as vitamin K.   [Note: it takes many other elements in the blood clotting process; people suffering from hemophilia do not have the ability to utilize one element with another, and this has nothing to do with vitamin K.] Vitamin K can be made from bacteria that live in the human gut.

Based on this it is actually not appropriate to classify it into the category of vitamins. However, babies are born with a sterile digestive tract, so they often give vitamin K injections to prevent too much bleeding in the event of a wound. At first, breast milk was considered a very lacking source of vitamins, until it was finally discovered that breast milk had a form of water-soluble vitamin in it.

Antibiotics, which are often used to cure infections, can destroy bacteria that produce vitamin K even for a temporary period of time. For patients undergoing antibiotic treatment, K is a “vitamin” that must be consumed. Green leafy vegetables are a good source of vitamin K.

Last Updated on March 13, 2021 Reviewed by Market Health Beauty Team

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