Phenylalanine is one of the four essential amino acids that are difficult to get from a vegetarian diet. Why should it matter? It relieves depression, elevates mood, decreases pain, boosts memory and suppresses your appetite. Like tryptophan and methionine, it's a quality of life amino acid.
There are three forms of phenylalanine: D–phenylalanine, which is made in the laboratory, L–phenylalanine, the natural form that's found in protein, and DL–phenylalanine, which is a combination of the other two forms.
Phenylalanine controls the release of the hormone cholecystokinin (CCK). This hormone tells the brain that you're satisfied after you eat. If you're trying to lose some weight, incorporate more foods that have this essential amino acid into your diet. You might feel more satisfied after eating less.
Your body converts phenylalanine into the amino acid tyrosine, which then gets transformed into the neurotransmitters norepinephrine that improves your mood. Since norepinephrine affects mood, phenylalanine has been suggested to treat depression.
D–phenylalanine is sometimes prescribed to treat chronic pain, but there aren't any studies that prove it works.
The best vegetarian food sources are eggs, dairy products, almonds, avocado, bananas, brewer's yeast, cheese, corn, cottage cheese, lima beans, nuts, peanuts, pumpkin seeds, sesame seeds, whole grains, soybeans, pecans, chickpeas, and lentils.
Deficiency symptoms include confusion, lack of energy, depression, decreased alertness, memory problems, and lack of appetite.
Kalorama Information, "Wellness Market Opportunities in the Aging American Population,"
Anti–Aging Physicians Directory and Research Guide