A well-researched general overview of vitamins and their roles in maintaining health
Vitamins are organic substances that are required in much lower amounts for maintaining health than carbohydrates, lipids, and proteins (hence are called micronutrients). Since the human body is unable to make these vitamins, consuming them through food is essential for good health.
Classification of micronutrients
What varieties of vitamins exist?
Generally speaking, there are two categories of vitamins.
1)Lipid soluble Vitamins
2) Water-soluble vitamins
Lipid soluble Vitamins:
Because they are ingested and transported with lipids, these vitamins are referred to as lipid-soluble.
It is rare for someone to be deficient in these vitamins because the body accumulates a lot of them.
Names of lipid-soluble Vitamins:
vitamin A
vitamin E
vitamin D
vitamin K
vitamin A:
It can be found in different forms like retinol (also called preformed vitamin A), retinal (aldehyde form), retinoid acid (obtained by oxidation of retinol) etc.
Note: Most of the functions of vitamin A are performed by retinoid acid form.
From which sources you can obtain vitamin A

The main sources of vitamin A include liver, kidney, and egg tissue from animals.
Fruits and veggies that are red, orange, or green are particularly rich in pro-vitamin A (also known as carotene).
Various uses of vitamin A
• It is crucial for maintaining the reproductive cycle.
• Play an important role in the visual cycle
• Promotes growth mechanism
• Maintains integrity of epithelial cells
Deficiency of vitamin A:
Vitamin A deficiency, although rare, causes
• Night blindness
• Dermatological issues for example acne
Vitamin E:
Tocopherols that appear naturally make up vitamin E. The prime tocopherols are alpha tocopherols.
From which sources you can get vitamin E: The greatest source of vitamin E is vegetable oil. It is moderately concentrated in the liver.
What functions do vitamin E perform: When administered to infants and young children, it prevents hemolysis, and the majority of antimakeup is brought on by its antioxidant properties.
Vitamin D:
It is made up of a collection of sterols with hormonal characteristics.
Vitamin D is unique from other vitamins in that it can be made in small amounts by your body. In the initial period of its development, sunlight is important.
From where you can obtain vitamin D:
Vitamin D is produced by the body when exposed to sunlight, and it is also present in fatty fish, liver, and egg yolk. Milk is not an excellent source of vitamin D.
Various uses of vitamin D:Its important action is to maintain an almost constant level of calcium in plasma. It does this by increasing uptake from gastrointestinal tract. Calcium intake helps to maintain a normal quantity of calcium in the blood plasma.
2) lowering its renal excretion
3) rising rates of bone resorption
vitamin D Deficiency
vitamin D deficiency may occur due to:
1)Decreased intake
2)Renal function impairment
Its deficiency causes rickets and osteocalcin in which bones become weak. The chances of bone fracture increase.
Vitamin K:
Vitamin K is also a fat-soluble vitamin. It has several active forms, such as phylloquinone (found in plants) and menaquinone (found in gut flora).
Sources of vitamin  K:
It is found in vegetables such as cabbage and spinach. Its animal sources are liver and egg yolk.
The intestinal flora of our digestive system  also synthesizes this vitamin.
Functions of vitamin K:
It is important for the synthesis of blood clotting proteins in the liver.
Water soluble vitamins
Water-soluble vitamins are rarely toxic because the kidneys can readily excrete them.
Names of water-soluble vitamins
vitamin B6
vitamin B1
vitamin B5
vitamin B9
vitamin B12
vitamin B6:
It consists of pyridoxine, pyridoxal (an aldehyde), and pyridoxamine(an amine) and has a pyridine structure.
From where you can get this vitamin
The three forms can be obtained from different sources for example pyridoxine is present in plants whereas pyridoxal and pyridoxine are obtained from animal sources.
Biochemical functions
They act as precursors of different coenzymes which play an important role in metabolism.
Note: The only water-soluble vitamin that can be harmful is this one. If taken in excessive doses, neurological symptoms develop.
vitamin B1:
Thiamine pyrophosphate is its biologically active form.
Functions of vitamin B1:
It also functions as a coenzyme.
Deficiency: Its absence leads to brain issues.
Alcohol consumption results in thiamine deficiency, which produces mental confusion, eye jerking, ataxia of the gait, and weak eye muscles.
vitamin B5:
The second name for this vitamin is pantothenic acid. It acts as an acyl carrier.
Sources of pantothenic Acid:
Eggs, liver and yeast are among the most important sources of this vitamin.
Deficiency: Its deficiency is rare.
vitamin B9:
The second name for this vitamin is folic acid. It acts as a coenzyme.
It is important in nucleotide metabolism.
Sources of folic acid
Leafy and dark green vegetables for example spinach, cabbage and mustard greens are good sources of
folic acid.

Pregnant women are most frequently deficient in it.
Spina bifida is one of the neural tube abnormalities brought on by folate deficiency. In order to lower the risk of neural tube defects (NTDs), it is recommended that pregnant women consume 0.4 mg of folate daily.
vitamin B12:
It is also called cobalamin.
Sources of cobalamin:
It is mainly synthesized by microorganisms that are present in our intestines.
Deficiency of cobalamin:
Its deficiency is seen in patients who fail to absorb this vitamin from the intestine. The main reason for this issue is a deficiency of intrinsic factors which is essential for its absorption. The deficiency results in pernicious anemia.
Vitamins are micronutrients but they are nutritionally very important as they play an important role in maintaining your health.

So take vitamins from the above-said sources and live a healthy life.