对于成人而言,有8种氨基酸是人体自身不能合成、必须从食物中摄取的,它们分别是:赖氨酸、色氨酸、苯丙氨酸、甲硫氨酸、苏氨酸、异亮氨酸、亮氨酸和缬氨酸。在这8种必需氨基酸中,甲硫氨酸又称蛋氨酸,是唯一的含硫必需氨基酸。它是体内活性甲基和硫的主要来源,与它相关的代谢产物一好一坏,有趣也需要警惕。 For adults, there are 8 kinds of amino acids that can not be synthesized by human body and must be taken from food. They are: lysine, tryptophan, phenylalanine, methionine, threonine, Leucine and Valine. Of these eight essential amino acids, methionine, also known as methionine, is the only sulfur-containing essential amino acid. It is the main source of active methyl and sulfur in the body, and the metabolites that are associated with it are a good and a bad, interesting and need to be vigilant.