Amino acids are organic compounds that combine to form proteins. When proteins are digested, amino acids are left. The human body requires a number of amino acids to grow and breakdown food. Amino acids are classified into two groups: - Essential amino acids must be supplied by food. These include cysteine, lysine, and tryptophan. Sources of essential amino acids include milk, cheese, eggs, certain meats, vegetables and grains.
- Nonessential amino acids are made by the body from the essential amino acids. They include aspartic acid, glutamic acid, and glycine.
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