Vitamins: What are they, and what do they do? (2022)

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Vitamins are organic compounds that people need in small quantities. Most vitamins need to come from food because the body either does not produce them or produces very little.

Each organism has different vitamin requirements. For example, humans need to get vitamin C from their diets — while dogs can produce all the vitamin C that they need.

For humans, vitamin D is not available in large enough quantities in food. The human body synthesizes the vitamin when exposed to sunlight, and this is the best source of vitamin D.

Different vitamins play different roles in the body, and a person requires a different amount of each vitamin to stay healthy.

This article explains what vitamins are, what they do, and which foods are good sources. Follow the links in blue below for more information about each vitamin.

Vitamins: What are they, and what do they do? (1)Share on Pinterest

Vitamins are organic substances present in minute amounts in natural foodstuffs. Having too little of any particular vitamin may increase the risk of developing certain health issues.

A vitamin is an organic compound, which means that it contains carbon. It is also an essential nutrient that the body may need to get from food.

There are currently 13 recognized vitamins.

Vitamins are either soluble, or dissolvable, in fat or water. We describe both types below:

Fat-soluble vitamins

Vitamins A, D, E, and K are fat-soluble. The body stores fat-soluble vitamins in fatty tissue and the liver, and reserves of these vitamins can stay in the body for days and sometimes months.

Dietary fats help the body absorb fat-soluble vitamins through the intestinal tract.

Water-soluble vitamins

Water-soluble vitamins do not stay in the body for long and cannot be stored. They leave the body via the urine. Because of this, people need a more regular supply of water-soluble vitamins than fat-soluble ones.

Vitamin C and all the B vitamins are water-soluble.

For more in-depth resources about vitamins, minerals, and supplements, visit our dedicated hub.

(Video) How do vitamins work? - Ginnie Trinh Nguyen

Below, learn about each currently recognized vitamin:

(Video) The ABCD’s of vitamins

Vitamin A

Chemical names: retinol, retinal, and “the four carotenoids,” including beta carotene.

  • It is fat-soluble.
  • Function: It is essential for eye health.
  • Deficiency: This may cause night blindness and keratomalacia, which causes the clear front layer of the eye to grow dry and cloudy.
  • Good sources: These include liver, cod liver oil, carrots, broccoli, sweet potatoes, butter, kale, spinach, pumpkins, collard greens, some cheeses, eggs, apricots, cantaloupe melon, and milk.

Learn more about vitamin A.

Vitamin B1

Chemical name: thiamine.

  • It is water-soluble.
  • Function: It is essential for producing various enzymes that help break down blood sugar.
  • Deficiency: This may cause beriberi and Wernicke-Korsakoff syndrome.
  • Good sources: These include yeast, pork, cereal grains, sunflower seeds, brown rice, whole grain rye, asparagus, kale, cauliflower, potatoes, oranges, liver, and eggs.

Find out more about vitamin B1.

Vitamin B2

Chemical name: riboflavin.

  • It is water-soluble.
  • Function: It is essential for the growth and development of body cells and helps metabolize food.
  • Deficiency: Symptoms include inflammation of the lips and fissures in the mouth.
  • Good sources: These include asparagus, bananas, persimmons, okra, chard, cottage cheese, milk, yogurt, meat, eggs, fish, and green beans.

Learn more about vitamin B2.

Vitamin B3

Chemical names: niacin, niacinamide.

  • It is water-soluble.
  • Function: The body needs niacin for the cells to grow and work correctly.
  • Deficiency: Low levels result in a health issue called pellagra, which causes diarrhea, skin changes, and intestinal upset.
  • Good sources: Examples include chicken, beef, tuna, salmon, milk, eggs, tomatoes, leafy vegetables, broccoli, carrots, nuts and seeds, tofu, and lentils.

Find out more about vitamin B3.

Vitamin B5

Chemical name: pantothenic acid.

  • It is water-soluble.
  • Function: It is necessary for producing energy and hormones.
  • Deficiency: Symptoms include paresthesia, or “pins and needles.”
  • Good sources: These include meats, whole grains, broccoli, avocados, and yogurt.

Learn more here about vitamin B5.

Vitamin B6

Chemical names: pyridoxine, pyridoxamine, pyridoxal.

  • It is water-soluble.
  • Function: It is vital for the formation of red blood cells.
  • Deficiency: Low levels may lead to anemia and peripheral neuropathy.
  • Good sources: These include chickpeas, beef liver, bananas, squash, and nuts.

Find out more about vitamin B6.

Vitamin B7

Chemical name: biotin.

  • It is water-soluble.
  • Function: It enables the body to metabolize proteins, fats, and carbohydrates. It also contributes to keratin, a structural protein in the skin, hair, and nails.
  • Deficiency: Low levels may cause dermatitis or inflammation of the intestines.
  • Good sources: These include egg yolk, liver, broccoli, spinach, and cheese.

Learn more about vitamin B7.

Vitamin B9

Chemical names: folic acid, folinic acid.

(Video) What are Vitamins?

  • It is water-soluble.
  • Functions: It is essential for making DNA and RNA.
  • Deficiency: During pregnancy, this can affect the fetus’s nervous system. Doctors recommend folic acid supplements before and during pregnancy.
  • Good sources: These include leafy vegetables, peas, legumes, liver, some fortified grain products, and sunflower seeds. Also, several fruits have moderate amounts.

Why is folate, another form of B9, important?

Vitamin B12

Chemical names: cyanocobalamin, hydroxocobalamin, methylcobalamin.

  • It is water-soluble.
  • Function: It is essential for a healthy nervous system.
  • Deficiency: Low levels may lead to neurological problems and some types of anemia.
  • Good sources: Examples include fish, shellfish, meat, poultry, eggs, milk and other dairy products, fortified cereals, fortified soy products, and fortified nutritional yeast.

Doctors may recommend that people with vegan diets take B12 supplements.

Why do we need vitamin B12?

Vitamin C

Chemical name: ascorbic acid.

  • It is water-soluble.
  • Function: It contributes to collagen production, wound healing, and bone formation. It also strengthens blood vessels, supports the immune system, helps the body absorb iron, and acts as an antioxidant.
  • Deficiency: This may result in scurvy, which causes bleeding gums, a loss of teeth, and poor tissue growth and wound healing.
  • Good sources: These include fruit and vegetables, but cooking destroys vitamin C.

Learn more about vitamin C.

Vitamin D

Chemical names: ergocalciferol, cholecalciferol.

  • It is fat-soluble.
  • Function: It is necessary for the healthy mineralization of bone.
  • Deficiency: This may cause rickets and osteomalacia, or softening of the bones.
  • Good sources: Exposure to UVB rays from the sun or other sources causes the body to produce vitamin D. Fatty fish, eggs, beef liver, and mushrooms also contain the vitamin.

Learn more about getting enough vitamin D.

Vitamin E

Chemical names: tocopherol, tocotrienol.

  • It is fat-soluble.
  • Function: Its antioxidant activity helps prevent oxidative stress, an issue that increases the risk of widespread inflammation and various diseases.
  • Deficiency: This is rare, but it may cause hemolytic anemia in newborns. This condition destroys blood cells.
  • Good sources: These include wheat germ, kiwis, almonds, eggs, nuts, leafy greens, and vegetable oils.

What are the symptoms of vitamin E deficiency?

Vitamin K

Chemical names: phylloquinone, menaquinone.

  • It is fat-soluble.
  • Function: It is necessary for blood clotting.
  • Deficiency: Low levels may cause an unusual susceptibility to bleeding, or bleeding diathesis.
  • Good sources: These include natto, leafy greens, pumpkins, figs, and parsley.

Why do we need vitamin K?

Vitamin supplements

(Video) Vitamins & Minerals | What Do They Do & Why Should I Take Vitamin Supplements?

Many people in the United States take multivitamins and other supplements, though these may not be necessary or helpful, according to research.

A balanced, varied diet that contains plenty of fruits and vegetables should be the primary source of vitamins. The Department of Health and Human Services provide up-to-date guidelines detailing the best ways to get enough nutrients from the diet.

Fortified foods and supplements may be appropriate in some cases, however, such as during pregnancy, for people with restricted diets, and for people with specific health issues.

Anyone taking supplements should be careful not to exceed the maximum dose, as research shows that taking too much of any vitamin can lead to health problems.

Also, some medications can interact with vitamin supplements. Overall, it is important to speak with a healthcare provider before trying any supplement.

Various supplements are available for purchase online.

When is the best time to take supplements?

Vitamins are essential nutrients that mainly come from foods. Each performs various roles in the body, and deficiencies of different vitamins can harm health in different ways.

Aim to get vitamins from a balanced, varied diet that contains plenty of fruits and vegetables. If a person is pregnant or has a health issue or a restricted diet, a doctor or nutritionist may recommend supplements.

(Video) Why are Vitamins Important? + more videos | #aumsum #kids #science #education #children


What are the 13 type of vitamins? ›

The 13 essential vitamins your body needs are vitamins A, C, D, E, K and the B vitamins: thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyroxidine (B6), biotin (B7), folate (B9) and cobalamin (B12).

What happens to your body when you take vitamin? ›

When your body gets an adequate amount of vitamins, you may feel more alert. As a part of the role vitamins play in boosting energy production, they also can help to diminish mental fatigue. These symptoms aren't very common, but for those who live with them, they can have noticeable effects.

How does vitamins help the body function? ›

What Do Vitamins and Minerals Do? Vitamins and minerals boost the immune system, support normal growth and development, and help cells and organs do their jobs.

What is the best vitamin for seniors? ›

Dietary supplements for older adults
  • Calcium: Calcium works with vitamin D to keep bones strong at all ages. Bone loss can lead to fractures in both older women and men. ...
  • Vitamin D: ...
  • Vitamin B6: This vitamin is needed to form red blood cells. ...
  • Vitamin B12: This helps keep your red blood cells and nerves healthy.
3 days ago

What is the most important vitamin to take? ›

The role it plays in so many bodily functions and the staggering amount of people who are deficient in it makes Vitamin D the most important vitamin for your body overall, and there's a good chance that you are not getting enough.

How do you know if vitamins are working? ›

Some people do need more of a certain vitamin or mineral for health reasons, but the only way to know for sure is by getting a blood test to see where you stand. Talk to your doctor about measuring the levels of key nutrients in your blood so you can be sure you are only getting what you need.

How long does it take vitamins to start working? ›

Generally speaking, the more severely deficient you are in a vitamin or nutrient, the faster you'll see a difference when taking supplements. However, in most cases, it takes around three to six weeks to see noticeable changes.

What vitamins Cannot be taken together? ›

Large doses of minerals can compete with each other to be absorbed. Don't use calcium, zinc, or magnesium supplements at the same time. Also, these three minerals are easier on your tummy when you take them with food, so if your doctor recommends them, have them at different meals or snacks.

How do I know what vitamins I need? ›

One way to figure out what vitamins and supplements to take is to look carefully at the nutritional value of all the foods in your diet and see how close you come to the RDI recommended by the FDA for each essential vitamin and mineral.

Why is vitamin D so important? ›

Vitamin D is a nutrient your body needs for building and maintaining healthy bones. That's because your body can only absorb calcium, the primary component of bone, when vitamin D is present. Vitamin D also regulates many other cellular functions in your body.

What causes vitamin deficiencies? ›

These may include:
  • Fatigue.
  • Shortness of breath.
  • Dizziness.
  • Pale or yellowish skin.
  • Irregular heartbeats.
  • Weight loss.
  • Numbness or tingling in the hands and feet.
  • Muscle weakness.
18 Jan 2022

What is vitamin B12 good for? ›

Vitamin B-12 (cobalamin) plays an essential role in red blood cell formation, cell metabolism, nerve function and the production of DNA, the molecules inside cells that carry genetic information. Food sources of vitamin B-12 include poultry, meat, fish and dairy products.

Which vitamins work best together? ›

5 Nutrients to Take – or Avoid Taking – Together for Best Absorption
  • Nutrient Absorption Guidelines.
  • Pair: Iron + Vitamin C.
  • Pair: Vitamin D + Calcium.
  • Pair: Vitamin B12 + Folate.
  • Pair: Vitamin D + Omega-3s.
  • Avoid: Iron + Calcium.
20 Sept 2019

Which vitamin is best for hair fall? ›

The 5 Best Vitamins for Hair Loss Prevention, Based on Research
  1. Biotin. Biotin (vitamin B7) is important for cells inside your body. ...
  2. Iron. Red blood cells need iron to carry oxygen. ...
  3. Vitamin C. Vitamin C is essential for your gut to absorb iron. ...
  4. Vitamin D. You might already know that vitamin D is important for bones. ...
  5. Zinc.
18 Nov 2020

What are the top 3 best vitamins to take? ›

According to Nutritionists, These Are the 7 Ingredients Your Multivitamin Should Have
  1. Vitamin D. Vitamin D helps our bodies absorb calcium, which is important for bone health. ...
  2. Magnesium. Magnesium is an essential nutrient, which means that we must get it from food or supplements. ...
  3. Calcium. ...
  4. Zinc. ...
  5. Iron. ...
  6. Folate. ...
  7. Vitamin B-12.

How can a 70 year old get more energy? ›

Here are nine great ways older adults can keep themselves healthier and more energetic.
  1. Proper Nutrition. A well-balanced diet is essential to consistent energy levels. ...
  2. Eating Breakfast. ...
  3. Green Tea. ...
  4. B Vitamin Supplements. ...
  5. Drinking Water. ...
  6. Magnesium. ...
  7. Daily Exercise. ...
  8. Consistent Sleep.
4 Jan 2017

Why do old people need vitamin B12? ›

B12 is important for creating red blood cells and DNA, and for maintaining healthy nerve function. “Getting enough B12 is a challenge for older people because they can't absorb it from food as well as younger people," says Tucker. "Even if your diet contains enough, you may be falling short."

What vitamin Should a woman take daily? ›

There are a few types of these nutrients, and they're all good for your body. But three of them -- vitamins B6, B12, and folic acid -- are especially important. Vitamin B6 is also known as pyridoxine. You need it to keep your brain working well and to help your body change food into energy, which is called metabolism.

What vitamins should I take to have more energy? ›

Can Supplements Improve Your Energy?
  • Vitamin B12.
  • Vitamin D.
  • Iron.
  • Magnesium.
  • Zinc.
  • Creatine.
  • Coenzyme Q10 (CoQ10)
  • Ashwagandha.
21 Jul 2021

What is zinc good for? ›

Zinc, a nutrient found throughout your body, helps your immune system and metabolism function. Zinc is also important to wound healing and your sense of taste and smell. With a varied diet, your body usually gets enough zinc. Food sources of zinc include chicken, red meat and fortified breakfast cereals.

Do we just pee out vitamins? ›

Water-soluble vitamins, like C, B and folic acid, aren't stored in the body and need to be topped up frequently to maintain healthy levels. However, you can only absorb so much and any that your body can't use are passed out of the body when you urinate.

How long should I take vitamins for? ›

It's going to take between 6 weeks and 3 months to correct most nutritional deficiencies. Another good example is iron – it takes 3 months for the human body to make new red blood cells. So as a general rule we usually aim for 3 months of supplementation.

Why do I get tired after taking vitamins? ›

Any vitamin, when taken in excess, has the potential to cause fatigue and result in numerous other adverse effects. But for a few vitamins, it's a documented side effect. Niacin: When taken in doses over 1,000 milligrams per day, niacin can cause fatigue, warns National Institutes of Health.

Which is better B complex or B12? ›

When it comes to the issue of vitamin B12 vs B complex, both types of vitamins are crucial. If you're lacking B12, consume more of it via supplements or food. If you're lacking vitamin B in general, consider B complex vitamins instead. Overall, both vitamins are essential nutrients.

Is it good to take a multivitamin everyday? ›

Most studies find no benefit from multivitamins in protecting the brain or heart. But There are potential benefits and no risks from a one daily standard multivitamin.

What are some deficiency symptoms? ›

8 Common Signs You're Deficient in Vitamins
  • Brittle hair and nails. A variety of factors may cause brittle hair and nails. ...
  • Mouth ulcers or cracks in the corners of the mouth. ...
  • Bleeding gums. ...
  • Poor night vision and white growths on the eyes. ...
  • Scaly patches and dandruff. ...
  • Hair loss. ...
  • Restless leg syndrome.
4 Nov 2019

Can I take 5 different vitamins at once? ›

You can—but it's probably not a good idea. For some supplements, optimal absorption can depend on the time of day taken. Not only that—taking certain vitamins, minerals, or other supplements together can also reduce absorption and may result in adverse interactions, which can be harmful to your health.

What vitamins should be taken at night? ›

4 Vitamins That Help You Sleep
  • Magnesium. Magnesium is perhaps the most important vitamin or mineral when it comes to sleep. ...
  • Calcium. Calcium has been shown to play a significant role in our sleep cycles, particularly the REM stage of sleep. ...
  • Potassium. ...
  • B Vitamins.
25 Feb 2022

What vitamins can you overdose on? ›

Any ingredient in a multiple vitamin supplement can be toxic in large amounts, but the most serious risk comes from iron or calcium. Additional risks are associated with large or toxic doses of calcium, vitamin D, and vitamin A.

How many different types of vitamins are there? ›

In humans there are 13 vitamins: 4 fat-soluble (A, D, E, and K) and 9 water-soluble (8 B vitamins and vitamin C).

What are types of vitamins? ›

They are:
  • Vitamin A.
  • Vitamin C.
  • Vitamin D.
  • Vitamin E.
  • Vitamin K.
  • Vitamin B1 (thiamine)
  • Vitamin B2 (riboflavin)
  • Vitamin B3 (niacin)
11 Mar 2021

Is there a vitamin Q? ›

Vitamin Q is another name for the coenzyme Q, also known as ubiquinone. It is an organic molecule similar in structure to vitamin K and vitamin E. Vitamin Q belongs to category of fat-soluble vitamins and may be stored in the body until it is needed.

What are the examples of vitamins? ›

Vitamins are substances that our bodies need to develop and function normally. They include vitamins A, C, D, E, and K, choline, and the B vitamins (thiamin, riboflavin, niacin, pantothenic acid, biotin, vitamin B6, vitamin B12, and folate/folic acid).

How do I know what vitamins I need? ›

One way to figure out what vitamins and supplements to take is to look carefully at the nutritional value of all the foods in your diet and see how close you come to the RDI recommended by the FDA for each essential vitamin and mineral.

Which vitamins should you not take together? ›

Here are six vitamin combinations you definitely shouldn't take together.
  • Magnesium and calcium/multivitamin. ...
  • Vitamins D, E and K. ...
  • Fish Oil & Gingko Biloba. ...
  • Copper and zinc. ...
  • Iron and Green tea. ...
  • Vitamin C and B12.
29 Aug 2022

Which vitamin is good for face? ›

Vitamin D is one of the best vitamins for your skin, along with vitamins C, E, and K. Making sure you get enough vitamins can keep your skin looking healthy and youthful.

What is vitamin b12 good for? ›

Vitamin B-12 (cobalamin) plays an essential role in red blood cell formation, cell metabolism, nerve function and the production of DNA, the molecules inside cells that carry genetic information. Food sources of vitamin B-12 include poultry, meat, fish and dairy products.

Which vitamins can you take too much of? ›

Dwyer says vitamin D, calcium, and folic acid are three nutrients you may get too much of, especially through supplements. Adults who regularly far exceed the 4,000 international units (IUs) daily safe upper limit for vitamin D might may end up with serious heart problems.

Which vitamins should be taken together? ›

Certain essential vitamins and minerals must be taken in combination to improve overall health.
  • Magnesium and vitamin D3. Magnesium and vitamin D3 supplements can be taken together to ensure that the body functions adequately. ...
  • Omega 3 and vitamin E. ...
  • Magnesium and zinc.
5 May 2021

Is there a vitamin F? ›

What is vitamin F? Vitamin F isn't actually a vitamin. It's made up of two kinds of polyunsaturated fatty acids. These fatty acids are alpha-linolenic acid (ALA) and linoleic acid (LA).

Is there a vitamin R? ›

A folic acid-related compound which promotes growth in bacteria; it is not a vitamin.

Is there a vitamin P? ›

Vitamin P is a term that was once used for a group of plant compounds called flavonoids. However, these compounds are not actually vitamins. There are several types of flavonoids found in fruits, vegetables, tea, cocoa, and wine.

Which vitamin helps with immune system? ›

Vitamin C is one of the biggest immune system boosters of all. In fact, a lack of vitamin C can even make you more prone to getting sick. Foods rich in vitamin C include oranges, grapefruits, tangerines, strawberries, bell peppers, spinach, kale and broccoli.

Which food contains all vitamins? ›

The top 15 foods highest in vitamins include fish, dark leafy greens, seeds, broccoli, pork, beef, lamb, mushrooms, nuts, eggs, sweet bell peppers, avocados, peas, winter squash, and fruits.

How long do vitamins stay in your body? ›

With all of that said, the exact time that water-soluble vitamins circulate in your body will depend on factors like age, nutrient status, diet, and the like. However, most are depleted within 1-2 days, which means replenishing them daily to ensure sufficient levels if critical for optimal health and performance 7.


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4. What's really inside your vitamins and supplements | 60 Minutes Australia
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