essential amino acid

noun

Definition of essential amino acid

: any of various amino acids that are required for normal health and growth in many vertebrates, are either not manufactured in the body or manufactured in insufficient quantities, are usually supplied by dietary protein, and include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine — compare nonessential amino acid

Examples of essential amino acid in a Sentence

Recent Examples on the Web Limiting the essential amino acid methionine appears to amplify the effects of radiation and chemotherapy in mice with colon cancer and sarcomas. Jocelyn Kaiser, Science | AAAS, 1 Apr. 2021 Tryptophan is an essential amino acid, according to the US National Library of Medicine's MedlinePlus website. Maggie O'neill, Health.com, 22 Feb. 2021 Food and drinks that contain certain minerals, therapeutic herbs and tryptophan — an essential amino acid — can aid your body's production of serotonin and melatonin. Kristen Rogers, CNN, 11 Aug. 2020 Quinoa, which is technically a seed, includes all essential amino acids (there are nine) that your body needs for repair and growth but can’t produce for itself. Maggie O'neill, Health.com, 30 Apr. 2020 Seitan is not a complete protein, lacking the essential amino acid lysine. NBC News, 31 Jan. 2020 Insects are the basis of many food webs in nature, are very rich in nutrients—including protein and all nine essential amino acids for human development—and can be delicious. Popular Science, 22 Apr. 2020 Eggs are a complete protein, containing all 9 essential amino acids necessary to rebuild muscles and tissues in our bodies. Zee Krstic, Good Housekeeping, 9 Jan. 2020 In the search for another path to the fountain of youth, researchers have been exploring the role of methionine and cysteine, two of the body's nine essential amino acids which contain sulfur. Sandee Lamotte, CNN, 3 Feb. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'essential amino acid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of essential amino acid

1911, in the meaning defined above

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Time Traveler for essential amino acid

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The first known use of essential amino acid was in 1911

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Cite this Entry

“Essential amino acid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/essential%20amino%20acid. Accessed 6 Dec. 2021.

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More Definitions for essential amino acid

essential amino acid

noun

Medical Definition of essential amino acid

: any of various alpha-amino acids that are required for normal health and growth, are either not manufactured in the body or manufactured in insufficient quantities, are usually supplied by dietary protein, and in humans include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine

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