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
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Limiting the essential amino acid methionine appears to amplify the effects of radiation and chemotherapy in mice with colon cancer and sarcomas.
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Jocelyn Kaiser, Science | AAAS, 1 Apr. 2021
Tryptophan is an essential amino acid, according to the US National Library of Medicine's MedlinePlus website.
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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.
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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.
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Maggie O'neill, Health.com, 30 Apr. 2020
Seitan is not a complete protein, lacking the essential amino acid lysine.
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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.
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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.
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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.
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Sandee Lamotte, CNN, 3 Feb. 2020
See MoreThese 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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“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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The first known use of essential amino acid was in 1911
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