essential amino acid

noun

Updated on: 3 Apr 2018

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

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Recent Examples of essential amino acid from the Web

Eggs are a complete protein, containing all 9 essential amino acids necessary to rebuild the muscles and tissues in our bodies.

— caroline walder, Good Housekeeping, "Here's Why Eggs Are One of the Best Things You Can Eat," 1 Mar. 2018
Chia seeds also contain key minerals like calcium and magnesium, and all nine essential amino acids.

— aliza abarbanel, Bon Appetit, "What Are Chia Seeds Good For Anyway?," 26 Jan. 2018
Most powders contain whey, soy or casein, high-quality proteins containing all nine essential amino acids that the body can't make on its own.

— katherine dillinger, CNN, "Protein powder pros and cons: What to know, what to watch out for," 9 Mar. 2018
Soy Protein: The Safe Bet Pro: Chock full of all nine essential amino acids.

— emily abbate, GQ, "Protein Powder Supplements, Explained: Your Complete Guide to the Smoothie Bar Menu," 5 Mar. 2018
Without niacin, the body cannot produce tryptophan, an essential amino acid.

— ben crair, Smithsonian, "Why Are These Hamsters Cannibalizing Their Young?," 21 Feb. 2018
The Kingsley clinics found that specifically eating 120 grams of protein—which contain all of the essential amino acids—at breakfast and lunch is ideal for keeping hair strong.

— alanna greco, Marie Claire, "6 Easy (and Salon-Free) Ways to Get Thicker Hair," 7 Sep. 2017
The ancient grain adds all nine essential amino acids to the dish.

— terri milligan, Milwaukee Journal Sentinel, "A bird in hand: Rotisserie chicken is the answer to many a dinner," 5 Sep. 2017
Just keep in mind that not all protein powders provide the entire range of essential amino acids that natural forms of protein can.

— alexandra sifferlin, Time, "5 Granola Bars That Are Actually Good For You," 1 Sep. 2017

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.

First Known Use of essential amino acid

1911

in the meaning defined above

See Words from the same year

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Medical Dictionary

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