vitamin

American  

[vahy-tuh-min, vit-uh-min] / ˈvaɪ tə mɪn, ˈvɪt ə mɪn /

British also vitamine

noun

vitamins plural

1. any of a group of organic substances essential in small quantities to normal metabolism, found in minute amounts in natural foodstuffs or sometimes produced synthetically: deficiencies of vitamins produce specific disorders.

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vitamin British  

/ ˈvɪtəmɪn, ˈvaɪ- /

noun

1. any of a group of substances that are essential, in small quantities, for the normal functioning of metabolism in the body. They cannot usually be synthesized in the body but they occur naturally in certain foods: insufficient supply of any particular vitamin results in a deficiency disease

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vitamin Scientific  

/ vī′tə-mĭn /

1. Any of various organic compounds that are needed in small amounts for normal growth and activity of the body. Most vitamins cannot be synthesized by the body, but are found naturally in foods obtained from plants and animals. Vitamins are either water-soluble or fat-soluble. Most water-soluble vitamins, such as the vitamin B complex, act as catalysts and coenzymes in metabolic processes and energy transfer and are excreted fairly rapidly. Fat-soluble vitamins, such as vitamins A, D, and E are necessary for the function or structural integrity of specific body tissues and membranes and are retained in the body.

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Closer Look

Although it has been known for thousands of years that certain diseases can be treated with specific foods, the scientific link between vitamins and good health wasn't made until the early 1900s by Polish-born American biochemist Casimir Funk. While studying beriberi, a disease that causes depression, fatigue, and nerve damage, Funk discovered an organic compound in rice husks that prevents the illness. He named the compound vitamine, derived from the chemical name amine and the Latin word vita, "life," because vitamins are required for life and were originally thought to be amines. Funk's compound is now known as vitamin B₁, or thiamine. His research and discovery led him, along with English biochemist Sir Frederick Gowland Hopkins, to propose the vitamin hypothesis of deficiency, which stated that certain diseases, such as scurvy or rickets, are caused by dietary deficiencies and can be avoided by taking vitamins. Further research allowed scientists to isolate and identify the vitamins that we know today to be essential for human health. Vitamins include A, C, D, E, K, thiamine, riboflavin, niacin, B₆, B₁₂, folic acid, biotin, and pantothenic acid. Vitamins are distinguished from minerals, such as calcium, iron, and magnesium, which are also essential for optimum health.

Other Word Forms

Derived Forms

• vitaminic
  adjective

Inflected Forms

Nouns

• vitamins
  plural

Etymology

Origin of vitamin

1912; earlier vitamine < Latin vīt ( a ) life + amine; coined by C. Funk, who thought they were amines

Explanation

A vitamin is an organic substance your body needs to keep working properly. Vitamins are important to health. Your body needs food and water to stay alive, but it also needs vitamins to work properly. You get some Vitamin D from the sun, and lots of Vitamin C from citrus fruits such as oranges. Without vitamins, your immune system can weaken. Many people take vitamins in pill form to help them stay healthy. The word vitamin — originally vitamine — was coined by scientist Casimir Funk in the early 1900s. He combined vita, Latin for "life," with amine, from amino acids.

Example Sentences

See Examples For:

vitamin vitamins

In fact, an analysis that Lilly previously conducted found that adding vitamin B-12 to compounded Zepbound created a “previously unidentified impurity.”

From MarketWatch ● Jul. 7, 2026

Plus, about one-third of the compounded drugs had added ingredients like vitamin B-12, which have not been studied in clinical trials.

From MarketWatch ● Jul. 7, 2026

However, relatively little research has examined whether vitamin C levels measured directly in the blood are associated with physical changes in the brain.

From Science Daily ● Jul. 1, 2026

Their work transformed medicine and eventually led scientists to identify vitamin B12 as the substance in liver that treated the disease.

From Science Daily ● Jun. 25, 2026

Not to mention that she’s wearing sweatpants that have seen too many wears, and a way-too-big T-shirt that says “I need vitamin sea” that I’m pretty sure is her dad’s.

From "Red Flags and Butterflies" by Sheryl Azzam

Researchers emphasize that high doses of vitamins, including niacin, can be toxic and may cause harm if they are not carefully monitored by medical professionals.

From Science Daily ● Jun. 22, 2026

Adding synthetic minerals and vitamins does not make them nutritious.

From MarketWatch ● Jun. 21, 2026

Add some vitamins and water, and if you’re lucky, you’re gonna have a rose.

From Los Angeles Times ● Jun. 12, 2026

"Different fruits and vegetables offer very different nutritional benefits beyond vitamins and minerals," he said.

From BBC ● Jun. 8, 2026

I mean at least get something with some vitamins in it.

From "The Catcher in the Rye" by J. D. Salinger

Related Words

• fiber
• food
• mineral