vitamin

American  

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

British also vitamine

noun

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

• vitaminic
  adjective

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

"A lot of people were suffering from chronic fatigue, constant headaches, low vitamin B12, which was subsequently causing things like heart palpitations and very foggy heads," she said.

From BBC • May 18, 2026

The new study found that vitamin B2 metabolism plays an important role in these protective defenses.

From Science Daily • May 15, 2026

The team believes this process could eventually be used as a cancer treatment by shutting down vitamin B2 metabolism in tumors and triggering cancer cell death.

From Science Daily • May 15, 2026

To explore the idea further, the researchers tested roseoflavin, a naturally occurring compound produced by bacteria that has a structure similar to vitamin B2.

From Science Daily • May 15, 2026

For example, we need vitamin C, which is only found in plants.

From "The Omnivore's Dilemma" by Michael Pollan

Related Words

• fiber
• food
• mineral