Table of ContentsView AllTable of ContentsDifferent Types of VitaminsFat-Soluble VitaminsWater-Soluble VitaminsShould I Supplement?Precautions
Table of ContentsView All
View All
Table of Contents
Different Types of Vitamins
Fat-Soluble Vitamins
Water-Soluble Vitamins
Should I Supplement?
Precautions
Vitamins are substances that are essential to human health. They are also nutrients and are found in many foods as well as dietary supplements.
There are 13 vitamins, all of which you need regularly and in small amounts for various vital bodily functions. These vital functions support your health and help sustain your energy. 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.
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There are two types of vitamins:fat-soluble and water-soluble.
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.
The fat-soluble vitamins are:
Water-soluble vitamins include the following:
Vitamins are needed for many body functions, including the following:
Although vitamins can have similar roles, each has a very distinct purpose.
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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. After you eat them, fat-soluble vitamins are absorbed in your intestines, but only in the presence of fat.Therefore,eating fatalong with fat-soluble vitamins may enhance their absorption.
All fat-soluble vitamins are essential, so your body can’t make them on its own. Even though your body can store fat-soluble vitamins for a short time, it’s vital to get all four through your diet regularly to avoid deficiencies, which can be serious.
Vitamin A (Retinol)
Vitamin Aplays a key role in immunity, growth and development, and reproduction. 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.
Besides dietary supplements, good sources of vitamin A include animal-based foods such as:
Plant-based foods containing vitamin A include:
Avitamin A deficiencyis rare in the United States and may result from a poor diet, infection, or other medical conditions. Common symptoms of a vitamin A deficiency include:
Vitamin D (Calciferol)
Vitamin Dmay be found in two forms: 25-hydroxyvitamin D (also known ascalcidiol) and 1,25-dihydroxyvitamin D (also known ascalcitriol). 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.
Adults between the ages of 19 and 70 years old need 15 mcg, or 600 international units (IU), of vitamin D per day. 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. Otherwise, vitamin D is found in limited amounts in foods, including:
Vitamin Ddeficiencyis fairly common, especially in the winter or in areas of the world where sun exposure is low. 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 (Alpha-Tocopherol)
Vitamin Eexists naturally in various chemical forms, butalpha-tocopherolis the only form important to human health.
As an antioxidant, vitamin E helps protect cells from potentially harmful molecules known as free radicals and prevents an imbalance of antioxidants and free radicals known as oxidative stress. Vitamin E is also important for immune function and gene expression.
The average daily intake for vitamin E is recommended to be 15 milligrams (mg) for anyone over the age of 14 years. Those who are breastfeeding should aim for 19 mg of vitamin E per day.
Vitamin E is widespread in foods and can be found in grains, seeds, nuts, spinach, broccoli, and certain fruits.Synthetic forms of vitamin E, likealpha-tocopheryl acetate (ATA),are typically found in dietary supplements.
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.
Vitamin K (Phylloquinone)
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 can 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 a vitamin K deficiency include:
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. Instead, water-soluble vitamins are digested and absorbed in the presence of water and then carried to organs and tissues that need them. Any leftover water-soluble vitamins are excreted.
You need water-soluble vitamins in varying levels every day.
Vitamin B1 (Thiamine)
Vitamin B1is essential for energy metabolism and helps your body turn food into energy. It is also key in growth and development and normal cell function.
Adult males over the age of 19 need 1.2 mg of thiamine per day while adult females need 1.1 mg per day. 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 person with a thiamine deficiency may experience fatigue, irritability, memory loss, low appetite, and weight loss. A severe deficiency may lead to a condition calledberiberior other brain, nerve, and muscle abnormalities.
Vitamin B2 (Riboflavin)
Vitamin B2is typically consumed asflavin mononucleotide(FMN) orflavin adenine dinucleotide(FAD).
This water-soluble vitamin plays key roles in energy metabolism, cell function, growth, development, and the metabolism of fats, drugs, and steroids. Vitamin B2 also helps produce certain enzymes and lowers levels ofhomocysteine(an amino acid).
It is recommended that males over the age of 19 consume 1.3 mg of riboflavin per day and females of the same age consume 1.1 mg per day. During pregnancy, 1.4 mg of daily riboflavin is recommended, while those who are breastfeeding need 1.6 mg.
Good sources of riboflavin are:
You can also find it in the following foods:
Riboflavin deficiency is very rare in the United States. It may cause symptoms such as the following:
If left untreated, a riboflavin deficiency may lead toanemiaandcataracts.
Vitamin B3 (Niacin)
Vitamin B3is referred to either asniacinor one of its types,nicotinic acidornicotinamide.
After age 19, males need 16 mg of niacin equivalents (NE) and females need 14 mg NE. 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:
Vitamin B5 (Pantothenic Acid)
Vitamin B5is needed to synthesize coenzyme A (CoA), which is essential to cellular metabolism, fatty acid synthesis, and gene expression.
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. Great sources of this vitamin are:
A deficiency in pantothenic acid is rare but possible, especially in those who are malnourished. A pantothenic acid deficiency may cause the following:
Vitamin B6 (Pyridoxine)
There are six vitamers (compounds that relieve a particular vitamin deficiency) of vitamin B6, withpyridoxinebeing the most common one.
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. During pregnancy, 1.9 mg of vitamin B6 per day is recommended, while 2.0 mg is recommended throughout breastfeeding.
Vitamin B6 can be found in both plant and animal foods. Good sources of vitamin B6 include:
A deficiency in vitamin B6 is rare but possible. Symptoms of a deficiency in this water-soluble vitamin include:
Vitamin B7 (Biotin)
Commonly known for its potential role in hair and nail health,vitamin B7has many important functions.
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.
Biotin is widespread in foods, and sources include:
Because biotin is common in foods, a biotin deficiency is rare. Signs of a biotin deficiency include:
Vitamin B9 (Folate)
Vitamin B9is naturally present in various foods. 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. Folate is also present in nuts, beans, fish, eggs, beans, dairy, meat, and grains.
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.
Vitamin B12 (Cobalamin)
Vitamin B12contains the chemical element cobalt, which is why it is also calledcobalamin.
This water-soluble vitamin is necessary for normal development, nervous system function,DNAsynthesis, and the conversion of homocysteine tomethionine(an important process that may lead to heart disease if disrupted).
Adults should try to get 2.4 mcg of vitamin B12 per day. Those needs increase during pregnancy and lactation. People who are pregnant need 2.6 mcg of B12 per day while those who are breastfeeding need 2.8 mcg per day.
Vitamin B12 is only naturally found in animal-based foods, like meat, eggs, dairy, and poultry. Some plant-based foods are fortified with vitamin B12, but people following aveganor vegetarian diet often need to use dietary supplements to meet their B12 needs.
Symptoms of this deficiency include:
Vitamin C (Ascorbic Acid)
Vitamin Cis the only water-soluble vitamin that is not a B vitamin.
Vitamin C is well-known for its antioxidant properties. It is also vital to making the proteincollagen, protein metabolism, immunity, the absorption of nonheme iron (iron from plant sources), and the synthesis of variousneurotransmitters.
Males over the age of 19 need 90 mg of vitamin C per day, and females of the same age need 75 mg. During pregnancy, 85 mg of vitamin C is recommended. Breastfeeding adults need 120 mg of vitamin C per day.
Vitamin C is found in many fruits and vegetables, especially:
A diet low in vitamin C may cause a deficiency. In severe cases, a vitamin C deficiency may causescurvy. Otherwise, symptoms of a vitamin C deficiency include weakness, irritability, weight loss, and muscle and joint aches.
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You can consume fat-soluble and water-soluble vitamins through foods or dietary supplements.
To reach your vitamin needs, a food-first approach is recommended. Most people get enough of each vitamin through a well-balanced diet with plenty of fruits, vegetables, grains, protein, dairy, and healthy fats.
Additionally, research shows that compared to supplements, vitamins, and other nutrients are absorbed better when consumed through foods.However, while dietary supplements should never replace food, they may be necessary for some people.
A healthcare provider may recommend using dietary supplements for the following:
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it does for prescription drugs. This means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider,registered dietitian nutritionist (RDN or RD), or pharmacist.
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There are some precautions to consider before using vitamin supplements.
While an allergy to a vitamin is extremely rare, it’s possible to be allergic to other ingredients and fillers that may be present in some supplements.
Therefore, you should avoid any vitamin supplements or other products that contain ingredients you’re allergic to. Seek immediate medical attention if you have asevere allergic reaction, including the symptoms of itching, hives, and shortness of breath.
Vitamins can become toxic if you use them excessively.
Vitamin toxicity(hypervitaminosis) may occur if vitamins are consumed in doses that are too high or chronically used in excess. 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.
Summary
Vitamins are organic substances that your body needs daily in 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.
A deficiency may occur if you don’t get enough of a vitamin and can cause mild to severe side effects.
Dietary supplements aren’t always necessary, as all vitamins are available in foods. However, some people may need dietary supplements to meet their vitamin needs due to different conditions like gastrointestinal issues.
To avoid toxicity, it’s important to follow dosing directions when using vitamin supplements. Talk with a healthcare provider to learn more about vitamins and whether you need to supplement.
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