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Which nine amino acids are essential in the human diet?
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Amino acid
The structure and function of amino acids.
Essential amino acids are those that the human body cannot synthesize on its own, or cannot produce in sufficient quantities, and therefore must be obtained through the diet. There are nine such amino acids required for human health:12
In addition to these, some amino acids are classified as "conditionally indispensable," meaning they may become essential under specific circumstances, such as during illness or in premature infants.12