Vitamin A Importance, Role in the Body, Benefits, Food Sources, Vitamin A Toxicity, Vitamin A Deficiency, Related Health Issues, Suggested consumption, Recommendations for Children and FAQ
What is Vitamin A?
Vitamin A is a group of unsaturated monohydric alcohol that contains the alicyclic ring.
It is insoluble in water but fat soluble. Vitamin A is a common term that is used for various fat-soluble substances such as retinol, retinyl palmitate, and beta-carotene.
Vitamin A Role and Importance in Human Body
Various metabolisms of Vitamin A are essential for vision, cellular differentiation, epithelial barrier function, and immune function. Vitamin A, along with other vitamins, minerals and other compounds, is an essential micronutrient. This means that our body cannot make it on its own and hence we have to take it through our diet.
Vitamin A derived from food is stored in the liver until it is required in the body and is bound to protein before being transported to where it’s needed.
The following article lets you know how important Vitamin A is for your body and how you can get it.
Importance of Vitamin A in the Human Body
Vitamin A is essential for many physiological processes, including maintaining the integrity and function of all surface tissues (epithelia); For example- skin, lining of the respiratory tract, intestines, bladder, inner ear and the eye.
Vitamin A helps in daily replacement of skin cells and ensures that tissues like conjunctiva are able to produce mucus and inhibit infection.
Vitamin A is essential for good eyesight in low light, maintaining a healthy immune system, for physical-mental development and for reproduction.
Vitamin A supports many of the body’s systems. For this reason, vitamin A deficiency is now known as ‘Vitamin A Deficiency Disorder’.
Importance and Benefits of Vitamin A in the Body
- For Eyes
Vitamin A is essential for healthy vision. This vitamin is required to convert the light that hits your eyes into electrical signals that can be sent to your brain. Vitamin A deficiency can lead to Night Blindness.
- Reduced the risk of Cancer
When abnormal body cells start to grow and divide in an uncontrolled way it is considered as Cancer. Since vitamin A plays an important role in the development of body cells, it can have an impact on preventing cancer. In observational studies, consuming high amounts of vitamin A in the form of beta-carotene is known to reduce the risk of certain types of cancer, including the Hawkins lymphoma, as well as cervical, lung and bladder cancers.
Importance of Vitamin A in maintaining body’s natural defense system is essential. This includes mucous barriers to your eyes, lungs, intestines and genitals that trap bacteria and other infectious agents. It is involved in the production and function of white blood cells, which help identify and clean bacteria and other germs from your blood flow.
- Acne Resistant
Acne is a chronic, inflammatory skin disorder. People with this condition develop painful spots and blackheads, usually on the face, back and chest. These spots occur when the sebaceous glands are clogged with dead skin and oil. These glands are found in the hair follicles on your skin and they produce sebum. Sebum is an oily, waxy substance that keeps your skin lubricated and waterproof.
- For Bones
With aging some nutrients are needed by the body to maintain healthy bones as. These include protein, calcium and vitamin D. However, it is necessary to eat enough vitamin A for proper bone development, and deficiency of this vitamin is associated with poor bone health. In fact, people with low levels of vitamin a in blood are at a higher risk of fractures than those with healthy levels.
- Promotes Healthy Growth and Reproduction
Vitamin A is essential for maintaining a healthy reproductive system in both men and women and to ensure normal structure and growth of the fetus during pregnancy.
Vitamin A is important in reproduction. Tests and studies done on mice have shown that the deficiency of this vitamin can block the growth of sperm cells in men, leading to infertility. In pregnant women, vitamin A plays a role in the structure and development of many major organs of an unborn child, including the skeleton, nervous system, heart, kidneys, eyes, lungs and pancreas.
It should be noted that an abundance of vitamin A can be harmful for the baby in the womb during pregnancy and this is likely to lead to birth defects.
Effects of Vitamin A abundance
Vitamin A is a fat-soluble vitamin that is stored in your body. This means that excessive use can lead to toxic levels.
Hypervitaminosis A is caused by taking too much preformed vitamin A through diet or supplements. Symptoms may include –
- Aches and even Death.
Although it can be caused by an excessive vitamin A rich diet; supplements and medications are less likely to develop the symptoms.
In addition, consuming excess vitamin A from plants does not carry the same risk, as its active conversion in the body is controlled.
Also Read: 16 Natural Ways to Increase Your Metabolism
What happens when you have Vitamin A Deficiency?
The best manifestation of vitamin A deficiency is xerophthalmia, a disorder associated with dryness of the eyes. Xerophthalmia causes various ocular expressions of vitamin A deficiency, from night blindness, conjunctivitis, and corneal xerosis to corneal ulceration and keratomalacia which eventually leads to blindness if not treated.
Another major consequence of vitamin A deficiency is an increased risk of serious infection. Infection increases the body’s demand for vitamin A and hence worsens the deficiency. Children can therefore become involved in a toxic cycle of deficiency and infection, for which vitamin A deficiency is attributed to a significant cause of death in children.
Foods that are Rich in Vitamin A
There are two major sources of vitamin A-
- Animal sources and
- Plant sources.
Some fats are needed in the diet to help absorb all the sources of vitamin A. The daily vitamin A recommended for adult males is 900 micrograms and 700 micrograms for adult women.
In animal sources, vitamin A is found as a retinol which is the ‘active’ type of vitamin A. Liver of animals including fish liver is a very good source of it. Other animal sources are- egg yolks (not white) and dairy products such as milk (including human breast milk), cheese and butter. Meat from the animal’s muscles is not a good source.
Plant sources contain vitamin A in the form of carotenoids which should be converted into retinol during digestion before the body uses it. Carotenoids are pigments that give plants their green color and red or orange color of some fruits and vegetables.
The sources of vitamin A plants include mango, papaya, many squashes, carrots, sweet potatoes and maize (but not the white type). Other good sources of vitamin A are red palm oil and buriti palm oil. (Note: Vitamin A is destroyed if the color of these oils is boiled to remove it.)
Some fruits and vegetables are easier to digest than others, and it has been found that dark green vegetables such as spinach are difficult to digest. Mashing after cooking these vegetables makes them easier to digest. When mashed they can be added to staples and can be easily fed to children who hate eating vegetables.
It is important that not all sources of vitamin A should be overcooked, as it can reduce vitamin A benefits. Ultraviolet light can reduce the amount of vitamin A in food, so drying fruits like mangoes should not be done in direct sunlight.
Diet that relies heavily on local carbohydrates, such as rice, kasawa, bajra and jowar, are low in vitamin A, unless vitamin rich foods are added.
How much Vitamin A is needed by a Child?
As the body of children is at a pace of development, they need relatively high vitamin A intake; almost half more than the adults. Another reason for high intake is that children are relatively more likely to get infections that increase metabolic rates and hence increase the rate of vitamin A they use.
Breast milk contains enough vitamin A for children up to the age of six months, after that the foods (given in addition to breast milk) should contain a lower amount of vitamin A.
For young children, a balanced diet rich in vitamin A should include at least 2-3 vitamin A-rich fruits and vegetables a day, as well as a slightly fatty food to help with absorption.
Young children are completely dependent on their mothers or other caregivers for their diet, and so it is important for the mother and caregiver to know what a healthy diet is for their children.
Also Read: 9 Health Effects of Milk Consumption
The above article discusses vitamin A benefits and importance in the human body and related information. These data are derived from reliable sources and provided only for educational purposes but not intended to replace medical help or expert’s advice.
Approach/consult a doctor for more information and any problems related to vitamin deficiency.
Also Read: Vitamin A Importance (Assamese)
1) What does ‘Hypervitaminosis’ mean?
A- Hypervitaminosis A is also known as vitamin A toxicity, a condition caused by excessive vitamin A in the body. The condition may be Acute or Chronic:
- Acute: Usually if the vitamin is overtaken, in a short time.
- Chronic: If vitamin A accumulates for a long time.
2) What are the tests approved for vitamin A deficiency/toxicity?
A- Vitamin A Blood Test:
- Deficiency: Less than 50 mcg/DL
- Toxicity: 200 mcg/DL
Serum retinol levels:
- Deficiency: less than 28μg/DL
3) Which doctor should I consult if I suspect vitamin A deficiency?
A- Talk to your family doctor and share your concerns if you suspect vitamin A deficiency. Most nutritional deficiencies are a result of poor diet and malnutrition and your doctor may recommend changes in your diet. He can also suggest some supplements and tests and send you to the expert.
4) How are fat soluble vitamins differ from water soluble vitamins?
A- Fat soluble vitamins are different from water soluble vitamins, as fat soluble vitamins are stored in the body for a long time in fat cells and excessive consumption can lead to toxicity. Fat soluble vitamins need fat in the food to absorb from blood flow during digestion. Excessive consumption of water soluble vitamins is not harmful as urine removes the amount of excess vitamins that are not required in the body.
5) Is too much vitamin A harmful?
A- Vitamin A is a fat soluble vitamin. Consuming this vitamin in a natural way from food items will not lead to toxicity. However, excessive consumption of vitamin A supplements without consulting a doctor can lead to vitamin A toxicity related problems.