Vitamins are substances that are essential to human health.
They are also nutrients and are found in many foods as well as dietary supplements.
These vital functions support your health and help sustain your energy.
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Many vitamin deficiencies can contribute to fatigue (extreme tiredness).
A balanced diet can prevent fatigue and other health issues like anemia or heart conditions.
This article covers the functions, sources, recommended intakes, and other important information for all vitamins.
Fat-soluble vitamins are so named because they dissolve in fats, while water-soluble vitamins dissolve in water.
Fat-soluble vitamins can be stored in fat in your body for days to weeks.
However, most water-soluble vitamins cannot be stored, and any excess is excreted through the urine.
Fat-Soluble Vitamins
While there are many water-soluble vitamins, there are just four fat-soluble vitamins.
Fat-soluble vitamins are found in plant and animal food sources.
All fat-soluble vitamins are essential, so your body can’t make them on its own.
It’s also needed for cell formation and healthy vision.
Adults need varying amounts of vitamin A, which depends on gender and certain life stages.
Males over the age of 19 need 900 micrograms (mcg)retinolactivity equivalents (RAE).
Females over the age of 19 need 700 mcg RAE of vitamin A per day.
However, adult females who are pregnant need 770 mcg RAE, while those who arebreastfeedingneed 1,300 mcg RAE.
Calcitriol is the active form of vitamin D.
Vitamin D is crucial to calcium absorption and maintenance.
The fat-soluble vitamin ensures calcium levels are adequate, which promotes bone health.
Other important roles of vitamin D include the inflammatory process, cell growth, immunity, and metabolism.
After age 70, you should aim for 20 mcg (800 IU) of vitamin D a day.
The best way to get vitamin D is through sun exposure.
A vitamin D deficiency may cause conditions of defective bone mineralization such asricketsin children andosteomalaciain adolescents and adults.
Both conditions affect normal bone growth and health.
Vitamin E is also important for immune function and gene expression.
Those who are breastfeeding should aim for 19 mg of vitamin E per day.
A deficiency in this fat-soluble vitamin is rare but possible, especially in areas of food insecurity.
Symptoms of a vitamin E deficiency in children include slow reflexes, difficulty walking, and poor coordination.
In adults, a deficiency may causehemolytic anemia, which can cause fatigue, among other issues.
Phylloquinone isavailable in foods, while menaquinones are produced by bacteria found in your gut.
Vitamin K is best-known for its role in blood-clotting.
Your body uses vitamin K to make proteins needed to clot the blood.
Vitamin K is also important for bone health, especially in older adults.
Adult males need 120 mcg of vitamin K per day.
Adult females need 90 mcg of vitamin K daily, including during pregnancy and breastfeeding.
Vitamin K is mostly found inleafy green vegetables,vegetable oils, and certain fruits.
you could get vitamin K in smaller amounts from meat, eggs, dairy products, and some fish.
Poor intake or absorption of vitamin K may result in a deficiency.
Signs of avitamin K deficiencyinclude:
Water-Soluble Vitamins
Vitamin Cand the eightB vitaminsmake up the water-soluble vitamins.
Unlike fat-soluble vitamins, water-soluble vitamins cannot be stored in the body in large amounts.
Any leftover water-soluble vitamins are excreted.
You need water-soluble vitamins in varying levels every day.
It is also key in growth and development and normal cell function.
People who arepregnantor breastfeeding should aim for 1.4 mg of thiamine per day.
Many foods and dietary supplements contain thiamine.
Food sources include:
Thiamine deficiency is most common in areas with food insecurity.
A severe deficiency may lead to a condition calledberiberior other brain, nerve, and muscle abnormalities.
Vitamin B2 also helps produce certain enzymes and lowers levels ofhomocysteine(an amino acid).
It may cause symptoms such as the following:
If left untreated, a riboflavin deficiency may lead toanemiaandcataracts.
NAD and NADP also have important roles in gene expression, cell communication,cholesterolsynthesis, and antioxidant function.
During pregnancy and lactation, 18 mg NE and 17 mg NE are recommended, respectively.
Vitamin B3 is fairly easy to find in animal- and plant-based foods.
Good sources of vitamin B3 include:
Aniacin deficiencyis most common in people living in extreme poverty.
The recommended intake of pantothenic acid for adult males and females is 5 mg daily.
People who are pregnant need 6 mg of B5 per day.
Lactation increases the need for pantothenic acid to 7 mg per day.
Fortunately, almost all plant and animal foods contain vitamin B5, at least to some degree.
Due to its many forms, vitamin B6 is considered to be very versatile.
It is important for protein metabolism, cognitive development, homocysteine maintenance, immune function, and glucose metabolism.
Adults between the ages of 19 and 50 years need 1.3 mg of vitamin B6 per day.
After the age of 50, males need 1.7 mg of B6 and females need 1.5 mg per day.
Vitamin B6 can be found in both plant and animal foods.
Biotin is needed to make five different enzymes involved in metabolism.
It’s also necessary for gene regulation and cell signaling.
It’s recommended that all adults get 30 mcg of biotin per day.
Folate or another form of B9, folic acid, may be found in dietary supplements.
Like many other B vitamins, vitamin B9 is essential to various metabolic processes.
It’s also vital to homocysteine regulation, DNA synthesis, and the prevention of neural tube defects.
Male and female adults need 400 mcg of dietary folate equivalents (DFE) per day.
Due to its importance for a growing fetus, pregnant people need 600 mcg DFE of folate per day.
During lactation, 500 mcg DFE is recommended.
Many fruits and vegetables contain folate.
Afolate deficiencymay occur due to poor diet, malabsorption, or certain health conditions.
Signs and symptoms of folate deficiency include:
Megaloblastic anemiamay also occur as a result of a folate deficiency.
Adults should make a run at get 2.4 mcg of vitamin B12 per day.
Those needs increase during pregnancy and lactation.
Vitamin B12 is only naturally found in animal-based foods, like meat, eggs, dairy, and poultry.
Vitamin C is well-known for its antioxidant properties.
Breastfeeding adults need 120 mg of vitamin C per day.
In severe cases, a vitamin C deficiency may causescurvy.
Should I Supplement?
you’ve got the option to consume fat-soluble and water-soluble vitamins through foods or dietary supplements.
To reach your vitamin needs, a food-first approach is recommended.
This means some supplement products may not contain what the label says.
Precautions
There are some precautions to consider before using vitamin supplements.
Therefore, you should avoid any vitamin supplements or other products that contain ingredients you’re allergic to.
There is some evidence ofhypersensitivityreactions sparked by using vitamin supplements.
However, this punch in of reaction is not well understood.
Vitamins can become toxic if you use them excessively.
Vitamin toxicity may be more likely to happen with the overuse offat-soluble vitaminsbecause they are stored in the body.
However, some water-soluble vitamins can also become toxic if misused.
Some vitamins may not be suitable for children.
Vitamins should only be given to children if recommended by ahealthcare provider.
To prevent any adverse events, only use vitamins as directed.
Be sure to follow dosing directions as listed on the supplement label or as given by a healthcare provider.
Summary
Vitamins are organicsubstances that your body needs dailyin varying amounts for many important processes.
They help you have enough energy and avoid issues like specific types of anemia and more.
There are two types of vitamins: fat-soluble and water-soluble.
Altogether, there are 13 essential vitamins, all found in various foods or dietary supplements.
Dietary supplements aren’t always necessary, as all vitamins are available in foods.
To avoid toxicity, it’s important to follow dosing directions when using vitamin supplements.
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