The Essential Amino Acids: What Are They and Why Do I Need Them?
Amino acids are made into approximately 20 different versions, and proteins require all of these at some level, so for your body to make a protein, it must have all 20 amino acids available. Your body can synthesize many of these amino acids from other molecules; however, nine amino acids cannot be made in your body. These are called the “essential” amino acids, because your diet must supply them for your survival. Examples of essential amino acids include leucine, methionine, phenylalanine, and tryptophan. All proteins have these essential amino acids, but your body requires them in certain amounts and ratios to each other. Animal foods contain these amino acids in ratios that are similar to those found in humans, while most plant-based foods do not. In the past, people were concerned that vegetarians and people whose diets consisted mostly of plant foods were at risk of protein deficiency since they were not eating “complete” proteins. More recently, this old theory has been rejected
