A 37-year-old female presents to your clinic to discuss her plans for a new
vegetarian diet. The patient heard from a friend about a new vegetarian diet
that promised rapid weight loss. The diet consists of many leafy vegetables
with no pork, chicken, beef, eggs, or milk. She is also planning on working out
regularly with the goal of running a marathon within the year. After listening
to the patient, you refer her to a nutritionist for further assistance and guidance.
What is an essential amino acid, and how many are there?
List the essential amino acids.